Phylogenetic Study of the Neotropical Fish Genera Creagrutus Gunther and Piabina Reinhardt (Teleostei: Ostariophysi: Characiformes), with a Revision of the Cis-Andean Species RICHARD P. VARI and ANTONY S. HAROLD SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY • NUMBER 6 1 3 SERIES PUBLICATIONS OF THE SMITHSONIAN INSTITUTION Emphasis upon publication as a means of "diffusing knowledge" was expressed by the first Secretary of the Smithsonian. In his formal plan for the institution, Joseph Henry outlined a program that included the following statement: "It is proposed to publish a series of reports, giving an account of the new discoveries in science, and of the changes made from year to year in all branches of knowledge." This theme of basic research has been adhered to through the years by thousands of titles issued in series publications under the Smithsonian imprint, commencing with Smithsonian Contributions to Knowledge in 1848 and continuing with the following active series: Smithsonian Contributions to Anthropology Smithsonian Contributions to Botany Smithsonian Contributions to the Earth Sciences Smithsonian Contributions to the Marine Sciences Smithsonian Contributions to Paleobiology Smithsonian Contributions to Zoology Smithsonian Folklife Studies Smithsonian Studies in Air and Space Smithsonian Studies in History and Technology In these series, the Institution publishes small papers and full-scale monographs that report the research and collections of its various museums and bureaux or of professional colleagues in the world of science and scholarship. The publications are distributed by mailing lists to libraries, universities, and similar institutions throughout the world. Papers or monographs submitted for series publication are received by the Smithsonian Institution Press, subject to its own review for format and style, only through departments of the various Smithsonian museums or bureaux, where the manuscripts are given substantive review. Press requirements for manuscript and art preparation are outlined on the inside back cover. Lawrence M. Small Secretary Smithsonian Institution S M I T H S O N I A N C O N T R I B U T I O N S T O Z O O L O G Y • N U M B E R 6 1 3 Phylogenetic Study of the Neotropical Fish Genera Creagrutus Giinther and Piabina Reinhardt (Teleostei: Ostariophysi: Characiformes), with a Revision of the Cis-Andean Species Richard P. Vari and Antony S. Harold Smithsonian Institution Press Washington, D.C. 2001 A B S T R A C T Vari, Richard P., and Antony S. Harold. Phylogenetic Study of the Neotropical Fish Genera Creagrutus Giinther and Piabina Reinhardt (Teleostei: Ostariophysi: Characiformes), with a Revision of the Cis-Andean Species. Smithsonian Contributions to Zoology, number 613, 239 pages, 97 figures, 60 tables, 2001.—Creagrutus Gunther (1864) and Piabina Reinhardt (1867) are diagnosed as a monophyletic assemblage on the basis of synapomorphies in various osteo- logical and soft anatomical systems. Synapomorphies in a subset of these systems diagnose each genus and partially resolve the intrageneric phylogeny within Creagrutus. Piabina was found to be nonmonophyletic as previously constituted and is restricted herein to its type spe- cies, P. argentea Reinhardt (1867). Creagrudite Myers (1927) and Creagrutops Schultz (1944) share the characters diagnostic for Creagrutus and are considered junior synonyms of that genus in order to make Creagrutus monophyletic. Piabarchus Myers (1928), based on a spe- cies originally described in Piabina, was found to lack the derived features of the Creagrutus- Piabina lineage. A total of 64 species are recognized in Creagrutus (including 37 new species), 56 of which occur east of the Andean Cordilleras and are reviewed in this paper. The number of Creagrutus species herein recognized represents 337% of the number of species considered valid prior to Harold and Vari (1994). Contrary to recent taxonomic practice, Piabina is recognized as distinct but is limited to a single species, P. argentea Reinhardt (1867), distributed in various rivers of eastern Brazil. Keys are provided to the species of Creagrutus and Piabina in the major drainage basins within the range of the genera. Creagrutus nasutus Gunther (1876) is considered a synonym of C. peruanus, and Creagru- tus boehlkei Gery (1972) is placed into the synonymy of C. amoenus. Creagrutus pellegrini Puyo (1943) is assigned to the characid genus Chalceus. Lectotypes are designated for Piabina argentea Reinhardt, Leporinus muelleri Gunther, Cre- agrutus nasutus Gunther, C. pearsoni Mahnert and G6ry, Piabina peruana Steindachner, and C. phasma Myers. OFFICIAL PUBLICATION DATE is handstamped in a limited number of initial copies and is recorded in the Institution's annual report, Annals of the Smithsonian Institution. SERIES COVER DESIGN: The coral Montastrea cavernosa (Linnaeus). Library of Congress Cataloging-in-Publication Data Van, Richard P. Phylogenetic study of the neotropical fish genera Creagrutus Gunther and Piabina Reinhardt (Teleostei: Ostario- physi: Characiformes), with a revision of the cis- Andean species / Richard P. Vari and Antony S. Harold p. cm.—(Smithsonian contributions to zoology ; no. 613) Includes bibliographical references (p.). 1. Creagrutus—Classification. 2. Piabina—Classification. I. Title. II. Series. QL1.S54 no. 613 [QL638.C5] 590s-dc21 [597\48] 2001042826 © The paper used in this publication meets the minimum requirements of the American National Standard for Permanence of Paper for Printed Library Materials Z39.48—1984. Contents Page Introduction 1 Methods and Material 4 Institutional Abbreviations 5 Osteological Preparations 5 Terminology 8 Acknowledgments 8 Character Description and Analysis 9 Phylogenetic Positions of Creagrudite, Creagrutops, and Piabina 11 Generic Assignment of Creagrutus molinus, C. planquettei, C. veruina, and C. xiphos 11 Jaws and Associated Ligaments 11 Premaxilla 11 Premaxillary Teeth 12 Maxilla 14 Maxillary Teeth 15 Primordial Ligament 16 Ligaments Associated with Dorsal Portion of Maxilla 18 Dentary 20 Dentary Foramen 21 Laterosensory Canal Segment in Dentary 22 Dentary Teeth 22 Anguloarticular 22 Suspensorium 23 Relationship of Ectopterygoid and Quadrate 23 Relationship of Mesopterygoid and Metapterygoid 24 Metapterygoid 25 Quadrate 25 Hyomandibula 26 Antorbital and Infraorbitals 26 Antorbital 26 First Infraorbital 26 Joint between First and Second Infraorbitals 27 Fourth Infraorbital 27 Fifth Infraorbital 28 Branchial Arches 28 Fourth Basibranchial Tooth-Plate 28 Fifth Ceratobranchial 29 Third Infrapharyngobranchial 30 Cranium 30 Mesethmoid 30 Frontal 31 Parietal 32 Dilatator Groove 32 Temporal Foramen 32 Sphenotic 33 Epioccipital 34 Vomer 34 iv SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY Pectoral Girdle 34 Mesocoracoid 34 Scapular Foramen 35 Contact between Coracoid and Cleithrum 35 First Postcleithrum 3 6 Squamation 36 Lateral Line 36 Lateral Line Scale Form 36 Post-Anal Scales 36 Pigmentation 37 Dorsal-Fin Pigmentation 37 Caudal-Fin Pigmentation 37 Humeral Mark Form 37 Midlateral Body Pigmentation 37 Miscellaneous 37 Epurals 37 Vertebrae 37 Notochordal Mineralizations 38 Phylogenetic Reconstruction 38 Monophyly of the Creagrutus and Piabina Clade 38 Monophyly ofPiabina 39 Monophyly of Creagrutus 39 Intrageneric Relationships within Creagrutus 39 Phylogenetic Position of Creagrutus molinus, C. planquettei, C. veruina, and C. xiphos 41 Comments on Piabarchus Myers 42 Genus Creagrutus Gunther 42 Status of Creagrutus, Piabina, Creagrudite, and Creagrutops 42 Status of Creagrutus pellegrini Puyo 43 Premaxillary Dentition in Creagrutus and Piabina 46 Keys to the Species of Creagrutus Gunther and Piabina Reinhardt East of the Andes 49 Key to the Species of Creagrutus in the Amazon Basin Other than the Rio Negro . . . 50 Key to the Species of Creagrutus in the Rio Negro Basin 53 Key to the Species of Creagrutus in the Rio Tocantins Basin 53 Key to the Species of Creagrutus in the Guianas, including the Rio Cuyuni 54 Key to the Species of Creagrutus in the Rio Orinoco Basin and Cis-Andean Carib- bean Versant Drainages 55 Key to the Species of Creagrutus and Piabina in the Rio de La Plata and Rio Sao Francisco Basins and Rivers of Southeastern Brazil 58 Species Accounts 58 Creagrutus amoenus Fowler, 1943 58 Creagrutus anary Fowler, 1913 63 Creagrutus atratus, new species 66 Creagrutus atrisignum Myers, 1927 69 Creagrutus barrigai, new species 71 Creagrutus beni Eigenmann, 1911 75 Creagrutus bolivari Schultz, 1944 79 Creagrutus britskii, new species 83 Creagrutus calai, new species 85 Creagrutus changae, new species 88 Creagrutus cochui Gery, 1964 91 Creagrutus cracentis, new species 93 Creagrutus crenatus, new species 95 NUMBER 613 Creagrutus ephippiatus, new species 98 Creagrutus figueiredoi, new species 101 Creagrutus flavescens, new species 104 Creagrutus gephyrus Bohlke and Saul, 1975 108 Creagrutus gracilis, new species I l l Creagrutus gyrospilus, new species 113 Creagrutus holmi, new species 116 Creagrutus hysginus Harold, Vari, Machado-Allison, and Provenzano, 1994 119 Creagrutus ignotus, new species 122 Creagrutus kunturus Vari, Harold, and Ortega, 1995 125 Creagrutus lassoi, new species 128 Creagrutus lepidus Vari, Harold, Lasso, and Machado-Allison, 1993 131 Creagrutus machadoi, new species 134 Creagrutus magoi, new species 137 Creagrutus manu, new species 140 Creagrutus maxillaris (Myers, 1927) 142 Creagrutus melanzonus Eigenmann, 1909 146 Creagrutus melasma Vari, Harold, and Taphom, 1994 149 Creagrutus menezesi, new species 153 Creagrutus meridionalis, new species 157 Creagrutus molinus, new species 159 Creagrutus mucipu, new species 162 Creagrutus muelleri (Giinther, 1859) 165 Creagrutus occidaneus, new species 167 Creagrutus ortegai, new species 170 Creagrutus ouranonastes, new species 173 Creagrutus paraguayensis Mahnert and Gery, 1988 175 Creagrutus pearsoni Mahnert and Gery, 1988 178 Creagrutus peruanus (Steindachner, 1875) 181 Creagrutus petilus, new species 184 Creagrutus phasma Myers, 1927 186 Creagrutus pila, new species 189 Creagrutus planquettei Gery and Renno, 1989 191 Creagrutus provenzanoi, new species 195 Creagrutus runa, new species 198 Creagrutus saxatilis, new species 200 Creagrutus seductus, new species 202 Creagrutus taphorni, new species 205 Creagrutus ungulus, new species 209 Creagrutus veruina, new species 213 Creagrutus vexillapinnus, new species 215 Creagrutus xiphos, new species 218 Creagrutus zephyrus, new species 220 Genus Piabina Reinhardt, 1867 223 Piabina argentea Reinhardt, 1867 224 Phylogenetic Biogeography of Creagrutus and Piabina 228 Comments on Creagrutus nigrostigmatus 229 Resumo 230 Literature Cited 231 Index 238 Phylogenetic Study of the Neotropical Fish Genera Creagrutus Giinther and Piabina Reinhardt (Teleostei: Ostariophysi: Characiformes), with a Revision of the Cis-Andean Species Richard P. Vari and Antony S. Harold Introduction Species of the characiform genera Creagrutus Giinther and Piabina Reinhardt inhabit a diversity of freshwater systems across the broad expanse of the Neotropics from Panama to Paraguay. Through that vast region, the more than five dozen species of Creagrutus and the single species of Piabina are most abundant in moderately to swiftly flowing water bodies. Species-level diversity within Creagrutus is greatest in the streams and rivers draining the piedmont of the eastern slopes of the central and northern Andes, the Pacific versant of north- ern Colombia, the Caribbean slopes of Colombia and Venezu- ela, the coastal ranges of the northern portions of the Rio Orinoco basin in Venezuela, and the uplands of the Brazilian and Guyana shields. Matching this broad distribution of Crea- grutus is its notable altitudinal range compared to that of most characiform genera, extending from near sea level at various sites on the continent to nearly 1900 m in southeastern Peru. Relatively high elevation distributions of Creagrutus species occur along a nearly 3000 km swath of the Andean Cordilleras Richard P. Vari, Department of Systematic Biology, Division of Fishes, National Museum of Natural History, Smithsonian Institution, Wash- ington, DC. 20560-0159. Antony S. Harold, Ghee Marine Labora- tory, College of Charleston, 205 Fort Johnson, Charleston, South Carolina, 29412. Review Chairman: Stanley H. Weitzman, Department of Systematic Biology, Division of Fishes, National Museum of Natural History, Smithsonian Institution. Reviewers: Carl. J. Ferraris, Jr., California Academy of Sciences, San Francisco: Michael E. Retzer, Center for Biodiversity, Illinois Natural History Survey, Champaign, Illinois; and Stanley H. Weitzman, National Museum of Natural History, Smithsonian Institution. extending from southern Peru to Venezuela, with the genus be- ing one of the few among characiforms known from above 1000 m elevations at multiple localities along both the Atlantic and Caribbean versants of the Andean Cordilleras (Ortega, 1992:43; Pefaur, 1988:487; Jimenez et al., 1998:24; this paper). Piabina, in contrast, has a distribution totally allopatric to that of Creagrutus, being limited to low to midlevel elevation local- ities in the eastern portions of Brazil and northeastern Para- guay. Creagrutus and Piabina are absent, or rare, in ichthyofaunal samples from lentic waters (Galacatos et al., 1996:894) and from low gradient streams and rivers, most notably those in the central portions of the Amazon basin. At least one species of Creagrutus, however, has been reported to be capable of sur- viving in drying pools (Beebe, 1945:84). Neither Creagrutus nor Piabina are known from the Pacific versant rivers of Ecua- dor, Peru, and Chile. East of the Andean Cordilleras both gen- era are apparently absent from Argentina, most of the shorter Atlantic coastal drainages of eastern and southeastern Brazil, and the southern portions of the Rio de La Plata basin, includ- ing the Rio Uruguay and lower sections of the Rio Paraguay and Rio Parana. Distinctive jaw and dentition modifications in Creagrutus and Piabina permit members of those genera to exploit special- ized food items selected from the bottom of water bodies (F. Lima, pers. comm., 1999), in particular small seeds and the aquatic and terrestrial life stages of a variety of insects. Supple- menting these food items are phytoplankton, mollusks, crusta- ceans, and, less commonly, fish scales (Barriga, 1982; pers. obs.) and smaller fishes (Godoy, 1975; Ortaz, 1992; K.O. Winemiller, pers. comm., 1999; pers. obs.). SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY TABLE 1.—Nominal species assigned herein to the genera Creagrutus and Piabina and recognized equivalent species according to the results of this study and that of Harold and Vari (1994). Nominal species are cited as in original description and arranged alphabetically by specific epithet. Species indicated by asterisks occur to the west of Andean Cordilleras in northwestern South American and southern Central America; these were dis- cussed in detail in Harold and Vari (1994). Nominal species Creagrutus affinis Steindachner, 1879* Creagrutus amoenus Fowler, 1943a Creagrutus anary Fowler, 1913 Piabina argentea Reinhardt, 1867 Creagrutus atratus, new species Creagrutus atrisignum Myers, 1927 Creagrutus barrigai, new species Creagrutus beni Eigenmann, 1911 Piabina beni Pearson, 1924 Creagrutus boehlkei Gery, 1972 Creagrutus bolivari Schultz, 1944 Creagrutus brevipinnis Eigenmann, 1913* Creagrutus britskii, new species Creagrutus calai, new species Creagrutus caucanus Eigenmann, 1913* Creagrutus changae, new species Creagrutus cijerri Creagrutus cochui Gery, 1964 Creagrutus cracentis, new species Creagrutus crenatus, new species Creagrutus ephippiatus. new species Creagrutus figueiredoi, new species Creagrutus flavescens, new species Creagrutus gephyrus Bohlke and Saul, 1975 Creagrutus gracilis, new species Creagrutus gyrospilus, new species Creagrutus hildebrandi Schultz, 1944* Creagrutus holmi, new species Creagrutus hysginus Harold et al., 1994 Creagrutus ignotus, new species Creagrutus kunturus Vari et al., 1995 Creagrutus lassoi, new species Creagrutus lepidus Vari et al., 1993 Creagrutus leuciscus Regan, 1913* Creagrutus londonoi Fowler, 1945c* Creagrutus machadoi, new species Creagrutus magdalenae Eigenmann, 1913* Creagrutus magoi, new species Creagrutus manu, new species Creagrutops maracaiboensis Schultz, 1944* Creagrudite maxillaris Myers, 1927 Creagrutus melanzonus Eigenmann, 1909 Creagrutus melasma Vari et al., 1994 Creagrutus menezesi, new species Creagrutus meridionalis, new species Creagrutus molinus, new species Creagrutus mucipu. new species Leporinus mulleri Giinther, 18S9 Creagrutus nasutus Giinther, 1876 Creagrutus nigrostigmatus Dahl, 1960* Creagrutus notropoides Meek and Hildebrand, 1912* Creagrutus occidaneus, new species Creagrutus ortegai, new species Creagrutus ouranonastes, new species Creagrutus paraguayensis Mahnert and Gery, 1988 Creagrutus paralacus Harold and Vari, 1994* Creagrutus pearsoni Mahnert and Gery, 19881 Creagrutus pellegrini Puyo, 1943 Creagrutus peruanus Steindachner, 1875 Assignment herein Creagrutus affinis Creagrutus amoenus Creagrutus anary Piabina argentea Creagrutus atratus Creagrutus atrisignum Creagrutus barrigai Creagrutus beni Creagrutus pearsoni{ Creagrutus amoenus Creagrutus bolivari Creagrutus brevipinnis Creagrutus britskii Creagrutus calai Creagrutus caucanus Creagrutus changae nomen nudum2 Creagrutus cochui Creagrutus cracentis Creagrutus crenatus Creagrutus ephippiatus Creagrutus figueiredoi Creagrutus flavescens Creagrutus gephyrus Creagrutus gracilis Creagrutus gyrospilus Creagrutus hildebrandi Creagrutus holmi Creagrutus hysginus Creagrutus ignotus Creagrutus kunturus Creagrutus lassoi Creagrutus lepidus Creagrutus affinis Creagrutus affinis Creagrutus machadoi Creagrutus magdalenae Creagrutus magoi Creagrutus manu Creagrutus maracaiboensis Creagrutus maxillaris Creagrutus melanzonus Creagrutus melasma Creagrutus menezesi Creagrutus meridionalis Creagrutus molinus Creagrutus mucipu Creagrutus muelleri Creagrutus peruanus Creagrutus nigrostigmatus Creagrutus affinis Creagrutus occidaneus Creagrutus ortegai Creagrutus ouranonastes Creagrutus paraguayensis Creagrutus paralacus Creagrutus pearsoni1 apparently a Chalceus species3 Creagrutus peruanus NUMBER 613 Table Nominal species Creagrutus petilus, new species Creagrutus phasma Myers, 1927 Creagrutus pila. new species Piabina piquira Creagrutus planquettei Gery and Renno, 1989 Creagrutus provenzanoi, new species Creagrutus runa, new species Creagrutus saxatilis, new species Creagrutus seductus, new species Creagrutus simus Meek and Hildebrand, 1913* Creagrutus taphorni, new species Creagrutus ungulus, new species Creagrutus veruina, new species Creagrutus vexillapinnus, new species Creagrutus xiphos. new species Creagrutus zephyrus, new species 1.-Continued. Assignment herein Creagrutus petilus Creagrutus phasma Creagrutus pila nomen nudum4 Creagrutus planquettei Creagrutus provenzanoi Creagrutus runa Creagrutus saxatilis Creagrutus seductus Creagrutus affin'is Creagrutus taphorni Creagrutus ungulus Creagrutus veruina Creagrutus vexillapinnus Creagrutus xiphos Creagrutus zephyrus 'Mahnert and Gery (1988:5) synonymized Piabina Reinhardt (1867) into Creagrutus Gunther (1864), an ac- tion that made Piabina heni a junior homonym of Creagrutus beni Eigenmann (1911). Mahnert and Gery conse- quently proposed pearsoni as a replacement for beni of Pearson (1924). 2 Creagrutus cijerri, listed by Bisbal and Sanchez (1997:267) in the listing of holotypes at MHNLS, is a nomen nudum based on a manuscript name of Fernandez- Yepez (C. Lasso, pers. comm., 2000). zCreagrutus pellegrini Puyo (1943:113) is apparently based on a Chalceus species (see "On the status of Cre- agrutus pellegrini Puyo" under "Genus Creagrutus Gunther"). * Piabina piquira listed by Eigenmann (1910:434) is apparently a nomen nudum (see "Remarks" under Pia- bina argentea). Less than 15 decades have passed since the first descriptions of species in the assemblage herein recognized as Creagrutus and Piabina (Gunther, 1859; Reinhardt, 1867, respectively). These dates are unexpectedly recent in light of the externally obvious distinguishing features shared by Creagrutus and Pia- bina, the broad distribution of the assemblage consisting of these taxa within South and southern Central America, and the relative abundance of many Creagrutus and Piabina species in appropriate habitats. Such a tardy recognition of this distinctive assemblage likely reflects the problems in sampling the ichthy- ofauna of the interior upland areas and the rapidly flowing streams typically inhabited by Creagrutus and Piabina species. Previous analyses of intrageneric diversity in Creagrutus were often constrained by limited population samples, a prob- lem compounded by the unavailability of type specimens to many researchers. As a consequence, intraspecific variation and interspecific differences within this assemblage were poorly understood. This taxonomic uncertainty contributed to the pervasive confusion concerning the geographic ranges of most species in the genus. Some Creagrutus species have been reported from a suspiciously broad swath of the continent (e.g., C. beni Eigenmann, which supposedly ranged from northeast- ern Bolivia to the Trans-Andean and eastern portions of Vene- zuela). Other nominal forms (e.g., C. anary Fowler), alterna- tively, were known only from their type series and few, if any, subsequent reports. These interlocking limitations made it dif- ficult, if not impossible, to confidently identify most samples of Creagrutus. More than seven decades ago in the last in-depth review of Creagrutus and Piabina, Eigenmann (1927) dealt with the 15 nominal species described to that time, 10 of which he recog- nized as valid. Subsequent decades saw an episodic, albeit pro- gressive, description of additional nominal species assigned to each genus. In overviews of Creagrutus, Piabina, Creagrudite Myers, and Creagrutops Schultz (the latter two taxa herein considered synonyms of Creagrutus), Gery (1964, 1977) rec- ognized 20 of the 26 species described to that time as valid. Two additional species were subsequently described by Mah- nert and Gery (1988) and Gery and Renno (1989) for a total of 28 nominal species, 22 of which were then recognized as valid. Three of these 22 species were, in turn, considered junior syn- onyms by Harold and Vari (1994) in their analysis of the Crea- grutus fauna to the west of the Andean Cordilleras. As a result, only 19 of the nominal Creagrutus species described prior 1994 were recognized as valid in the literature at that time. The Trans-Andean Creagrutus species of northwestern South America and southern Central America were analyzed by Harold and Vari (1994) who recognized eight species, in- cluding one previously undescribed form, in that region. The previously unrecognized diversity within Creagrutus east of the Andean Cordilleras was partially addressed by Vari et al. (1993, 1994, 1995) and Harold et al. (1994). Those publica- tions, in conjunction with the conclusions reported herein, demonstrate a dramatically higher intrageneric diversity within Creagrutus than previously suspected but at the same time ne- cessitate a more restricted concept of Piabina than utilized by many prior authors. Creagrutus, in the sense of this study, con- sists of 64 species (Table 1), 37 of which are first described herein and five of which were described in our earlier publica- tions (Harold and Vari, 1994; Harold et al., 1994; Vari et al., SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY 1993, 1994, 1995). This increase from 19 to 64 species (337%) is symptomatic of the problems that bedeviled earlier attempts at species-level determinations within Creagrutus. Such pro- nounced increase in the recognizable species of Creagrutus is undoubtedly paralleled by comparable undetected species di- versity in many genera of South American freshwater fishes of small to moderate body sizes, particularly in groups such as Creagrutus that inhabit distinct, patchily distributed habitats. Mirroring the species-level uncertainties within Creagrutus and Piabina were quandaries in unequivocally diagnosing each genus. Prior faunal and systematic studies included within Cre- agrutus the majority of species herein assigned to that genus. Nonetheless, some species of Creagrutus, as diagnosed herein, were assigned to three separate, albeit externally similar and evidently closely related, taxa. The first of these, Piabina, was proposed by Reinhardt (1867) for a single species from eastern Brazil. Piabina was synonymized into Creagrutus by Eigen- mann and Eigenmann (1891), resurrected from that synonymy without discussion by Eigenmann (1910), and expanded by Eigenmann (in Eigenmann et al., 1914) and Pearson (1924). One of the nominal Piabina species subsequently was shifted to Piabarchus by Myers (1928), a genus that was proposed at the same time. More recently, Piabina was again returned to the synonymy of Creagrutus by Mahnert and Gery (1988), a synonymy not, however, derived from a new phylogenetic per- spective. The decision rather was a consequence of the obser- vation that the purported gap in anal-fin ray counts between Creagrutus and Piabina, the character traditionally used to dis- tinguish the genera, was bridged by the anal-fin ray counts in various nominal Creagrutus species and, thus, failed to dis- criminate the genera. A third nominal genus allied with Creagrutus is Creagrudite, which was originally proposed by Myers (1927) for a Creagru- tus-like species with distinctive dentition in both jaws, most notably the presence of only two distinct rows of teeth on the premaxilla. Creagrudite was synonymized into Creagrutus by Bohlke and Saul (1975) following their discovery of C. ge- phyrus, a species with oral dentition they considered intermedi- ate between that occurring in Creagrudite and that typical for most Creagrutus species. That synonymy has not, however, been evaluated within a broader phylogenetic study. Finally, Creagrutops was proposed by Schultz (1944) for a diminutive species characterized by apparently reductive features. This ge- nus was synonymized into Creagrutus by Harold and Vari (1994). Although providing preliminary justification for their action, Harold and Vari (1994) deferred a definitive statement on the phylogenetic placement of the single nominal species, Creagrutops maracaiboensis, within Creagrutus pending fur- ther studies. In our review of the Trans-Andean Creagrutus species (Harold and Vari, 1994), we neither delved into the questions of the monophyly of Creagrutus and generic phylogenetic in- trarelationships, nor addressed the problem of the phylogenetic relationships of taxa assigned at various times to Creagrutus, Creagrudite, Creagrutops, and Piabina. Vari and Harold (1998) used a subset of the characters discussed in this study to approach the question of the relationships of Creagrutus and Piabina and of the monophyly of each genus. An analysis of the intrageneric relationships in Creagrutus would have been premature in the absence of a thorough review of the recogniz- able species of that genus occurring east of the Andes, a com- plex problem first addressed in this paper. In this paper we provide a revision of all species of Creagru- tus and Piabina known from east of the Andean Cordilleras (see Harold and Vari (1994) for a revision of the Trans-Andean Creagrutus species in northwestern South America and south- ern Central America). Hypotheses on the monophyly of the clade consisting of Creagrutus and Piabina and of each genus are advanced based both on the characters discussed by Vari and Harold (1998) and those found in other body systems. A hypothesis of the intrageneric phylogenetic relationships within Creagrutus is proposed on the basis of shared derived anatomical features. In the absence of an explicit hypothesis of the placement of Creagrutus and Piabina within characiforms, our outgroup ob- servations were expanded to include a diversity of characi- forms. These focus on the Characidae, with a particular empha- sis on the Tetragonopterinae (see discussion under "Character Description and Analysis," below). The intrageneric analysis serves, in turn, as the basis for a discussion of the historical biogeography of the clade formed by Creagrutus and Piabina and subunits within Creagrutus. METHODS AND MATERIAL Measurements were made with dial calipers or an ocular mi- crometer with data recorded to tenths of a millimeter. Counts and measurements were made on the left side of specimens when possible and follow the methods outlined in Harold and Vari (1994:2). During the course of this study one additional useful meristic feature was discovered, the variation in the number of post-anal scales. These are the number of median scales between the posterior rim of the anus and the base of the first anal-fin ray. Counts of scale rows between the lateral line and anal fin do not include the scales in the sheath of scales overlying the base of the anterior rays of the anal fin found in some Creagrutus species living east of the Andean cordilleras. The number, distribution, and form of the premaxillary teeth in characiforms usually are most readily studied by the careful depression of the lower jaw. Various modifications of the lower jaw and associated bones and musculature in well-preserved specimens of most Creagrutus species make the depression of the lower jaw difficult, if not impossible, without severe dam- age to the dentary and/or the dentary teeth. Retraction of the typically fleshy lower lip by careful manipulation allows exam- ination of the premaxillary and maxillary dentition without forcing the lower jaw open or damaging the lower lip. Cleared and stained or counterstained specimens (see below) served as NUMBER 613 supplemental sources of information on premaxillary and max- illary dentition and as a primary source of data on dentary teeth. The first entry under the "Material Examined" section for each species summarizes the total number of specimens exam- ined (with the number in parentheses being the specimens forming the basis for the meristic and morphometric data and the range of standard lengths for those specimens). This entry is followed by a geographically sorted listing of the material examined, including collection locality, institutional abbrevia- tion, catalog number, and number of specimens in the lot (in parentheses, the number of specimens in the lot from which counts and measurements were taken if that number is less than the total number of specimens in the lot, and the range of stan- dard lengths (in mm) of the individuals whose standard length could be accurately determined). Information on collectors and date of collection are in- cluded, when available, only for type series of species de- scribed in this paper. As a consequence of limited samples and the poor condition of available juveniles for most species, most presented morphometric ranges do not include juvenile specimens other than when the species is only known from smaller individuals. Mature males were identified by the pres- ence of bony hooks on the anal and sometimes the pelvic fins, with sex confirmed in a subsample via examination of the go- nads. The presence and/or relative development of such bony hooks in mature males may vary on a seasonal basis, and an understanding of this variability requires life history studies beyond the scope of this project. Geographic descriptors are in the sequence of country (small capital letters), state, province, department or district (itali- cized), followed by specific locality data. Country names are in English, but more specific locality information is in the lan- guage of the country in question. References to the Rio Negro basin, which is mostly in Brazil, follow the Portuguese and do not accent Rio. Exceptions involve references to Venezuelan or Colombian localities in which the form Rio is used. Latitude and longitude are either taken directly from data associated with the specimens or, if such data was originally lacking, from gazetteers in those instances in which a locality could be un- equivocally identified. The locality coordinates for material collected in the Rio Madeira basin by the Expedicao Perma- nente de Amazonia were taken from Heyer (1977). Common names are taken from previously published accounts. In the synonymies for each species, type localities are presented as originally cited, followed by a translation into English when necessary. Other citations are presented in English followed by the modern or corrected equivalents, in parentheses, if those are known to differ. Ecological and life history information provided for some of the species in this paper are based on diverse sources, including literature information, stomach content analyses conducted during this study, personal communications, catalog databases, and field notes. The co-occurrence of two or more Creagrutus species in a sample or at a locality is noted when such informa- tion is available. Such occurrence information is not presented for the nonCreagrutus species at those collecting sites. Nonpatronymic species names proposed in this study are based on Brown (1956). INSTITUTIONAL ABBREVIATIONS.—The following abbrevia- tions for institutions and collections are used: AMNH American Museum of Natural History, New York ANSP Academy of Natural Sciences of Philadelphia BMNH The Natural History Museum, London, formerly, British Mu- seum (Natural History) CAS California Academy of Sciences, San Francisco CBF Coleccion Boliviana de Fauna, La Paz CM Carnegie Museum, Pittsburgh (fish collections now mostly at FMNH) FML Fundacion Miguel Lillo, San Miguel de Tucuman FMNH Field Museum of Natural History, Chicago 1CLMA lnstituto de Ciencias e Letras do Medio Araguaia, Universidad Federal do Mato Grosso, Barra da Garcas ICNMHN lnstituto de Ciencias Natural, Museo de Historia Natural, Bogota 1NHS Illinois Natural History Survey, Champaign IU Former Indiana University collections (now dispersed to vari- ous repositories) KU Museum of Natural History, University of Kansas, Lawrence LACM Los Angeles County Museum of Natural History MBUCV Museo de Biologia, Universidad Central de Venezuela, Caracas MCNG Museu de Ciencias Naturales, Guanare, Venezuela MCP Museu de Ciencias e Tecnologia, Pontificia Universidade Catolica do Rio Grande do Sul, Porto Alegre MCZ Museum of Comparative Zoology, Cambridge MEPN Museo, Escuela Politecnica Nacional, Quito MHNG Museum d'Histoire Naturelle, Geneva MHNLS Museo de Historia Natural La Salle, Caracas MNHN Museum National d'Histoire Naturelle, Paris MNHNP Museo Nacional de Historia Natural del Paraguay, Asuncion MNRJ Museu Nacional, Rio de Janeiro MTD Staatliches Museum fur Tierkunde, Dresden MUSM Museo de Historia Natural de la Universidad Nacional Mayor de San Marcos, Lima MZUSP Museu de Zoologia, Universidade de Sao Paulo, Sao Paulo NMNH National Museum of Natural History, Smithsonian Institution, Washington, DC. NMW Naturhistorisches Museum Wien, Vienna NNM Nationaal Natuurhistorisch Museum, Leiden NRM Naturhistoriska Riksmuseet, Stockholm ORSTOM Centre ORSTOM de Cayenne, French Guiana ROM Royal Ontario Museum, Toronto SU Stanford University (fish collections now deposited at CAS) UF Florida Museum of Natural History, Gainesville UMMZ University of Michigan, Museum of Zoology, Ann Arbor USNM Former United States National Museum, collections in the Na- tional Museum of Natural History, Smithsonian Institution, Washington, D.C. ZMA Instituut voor Systematiek and Populatiebiologie, Amsterdam ZMH Zoologisches Institut und Zoologisches Museum, Hamburg ZMUC Zoologisk Museum, Copenhagen ZSM Zoologische Staatssammlung, Munich OSTEOLOGICAL PREPARATIONS.—The vast majority of the osteological preparations were cleared and counterstained for SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY cartilage and bone using a modification of the method outlined by Taylor and Van Dyke (1985). Previously cleared specimens stained solely with alizarin Red-S were supplemental sources of osteological data and are indicated by (AR) in the following listing. The following cleared and stained specimens served as the basis for most observations in the phylogenetic analysis. The number following the catalog number indicates the num- ber of specimens cleared. Standard length is indicated in milli- meters. Locality data in the following list are typically abbrevi- ated, with complete information on Creagrutus and Piabina specimens provided in the species accounts of this paper for the Cis-Andean species and in Harold and Vari (1994) for Trans- Andean Creagrutus endemics. Creagrutus and Piabina species Creagrutus qffinis, USNM 78562, 1, 48.7 mm; Panama, Rio Boqueron. USNM 310414,2, 36.7-43.8 mm; Panama, Colon, Rio Morti. USNM 293249, 2, 26.7^*2.3 mm; Panama, Rio Pucuro. ANSP 71619, 1 (AR), 33.3 mm, paratype of Crea- grutus londonoi; Colombia, Rio Magdalena basin, Honda. Creagrutus amoenus, ANSP 70503, 1 (AR), 47.9 mm, paratype; Colombia, Caqueta, Florencia. USNM 311339, 1, 65.0 mm; Ecuador, Pastaza, Rio Danta, tributary to Rio Con- ambo. USNM 164070, 1, 62.4 mm; Ecuador, Napo, Rio Tut- apishco, near Loreto. Creagrutus anary, MZUSP 35604, 2, 40.4-^4.4 mm; Brazil, Amazonas, Rio Madeira, Cachoeira de Santo Antonio. Creagrutus atratus, USNM 353867, 2, 47.5-63.4 mm; paratypes, Colombia, Cundinamarca, mouth of Rio Saname, Rio Meta basin. Creagrutus atrisignum, USNM 341479, 1, 50.1 mm; Brazil, Goias, Niquelandia, Ribeirao do Engenho. Creagrutus barrigai, USNM 340976, 2, 40.8-45.6 mm, paratypes; Ecuador, Sucumbios, Rio Aguarico, upstream of Zancudo. Creagrutus beni, USNM 340959, 2, 36.4-^13.0 mm; Bolivia, Cochabamba, Rio Chapare basin, Villa Tunari. Creagrutus bolivari, ANSP 159831, 2,40.7-48.2 mm SL; Ven- ezuela, Bolivar, Rio Cariapo basin. NRM 16844,2, 51.7-54.7 mm; Colombia, Meta, Rio Meta basin. Creagrutus brevipinnis, USNM 120148, 2, 44.7-46.8 mm; Co- lombia, tributary of upper Rio Cauca. Creagrutus britskii, USNM 340952, 2, 35.8-39.3 mm, paratypes; Brazil, Goias, Iaciara, Ribeirao Macambira. Creagrutus calai, USNM 353304,2,44.8-49.0 mm, paratypes; Colombia, Meta, Cano Emma, Finca El Viento. Creagrutus caucanus, USNM 79187, 1, 69.2 mm; Colombia, Valle, Paila. USNM 120147, 1, 45.8 mm; Colombia, upper Rio Cauca. Creagrutus changae, USNM 285276, 2, 50.6-55.5 mm, paratypes; Peru, Huanuco, Rio San Alejandro. Creagrutus cochui, MZUSP 28055, 2, 64.2-66.4 mm; Brazil, Amazonas, Rio lea. Creagrutus cracentis, USNM 353862, 1, 26.1 mm, paratype; Brazil, Para, Rio Tapajos, 5 km S of Itaituba. Creagrutus crenatus. MHNLS 12900, 1, 57.0 mm, paratype; Venezuela, Lara, Quebrada Sanare, in Yay. INHS 28851, 1, 43.6 mm, paratype; Venezuela, Lara, Rio Curarigua, Puente Torres. Creagrutus ephippiatus, MBUCV V-18559, 2, 55.1-55.8 mm, paratypes; Venezuela, Amazonas, upper Rio Siapa. Creagrutus figueiredoi, USNM 292221, 3, 60.7-63.0 mm, paratypes; Brazil, Distrito Federal, Rio Maranhao. Creagrutus flavescens, USNM 340973, 2, 58.1-58.7 mm; Ec- uador, Sucumbios, Rio San Miguel basin, Rio La Bermeja. Creagrutus gephyrus, USNM 324461, 1, 41.3 mm; Ecuador, Napo, Rio Napo, at Coca. USNM 340953, 1,47.4 mm; Ecua- dor, Napo, Rio Napo, approximately 25 km downstream of Coca. Creagrutus gracilis, USNM 341370, 2, 36.1^2.1 mm, paratypes; Peru, Amazonas, Rio Santiago. Creagrutus gyrospilus, INHS 51282, 2, 51.9-55.8 mm, paratypes; Venezuela, Portuguesa, Rio Saguaz. Creagrutus hildebrandi, USNM 121487, 1,43.2 mm, paratype; Venezuela, Rio Palmar near Totuma. USNM 121484, 2, 26.7-40.5 mm, paratypes; Venezuela, Rio San Juan. Creagrutus holmi. USNM 167816, 3 (AR), 39.4-57.8 mm; Peru, Cajamarca, Balsas. USNM 341368, 1, 55.4 mm, paratype; Peru, Amazonas, Rio Maranon basin, Bagua Grande. Creagrutus hysginus, USNM 326035, 2, 36.1-42.7 mm, paratypes; USNM 326055, 2, 39.5-41.3 mm, paratypes; MBUCV-V 20304, 1, 38.0 mm, paratype; Venezuela, Sucre, Rio La Toma. CAS 79623, 1, 41.3 mm, paratype; Venezuela, Sucre, Rio Guiria. Creagrutus ignotus, USNM 326672, 1, 28.1 mm, paratype; Brazil, Mato Grosso, Diamantino. Creagrutus kunturus, USNM 335147, 1, 68.6 mm, paratype; Peru, Amazonas, Rio Comainas basin. Creagrutus lassoi, MCNG 24685, 2, 41.9-57.6 mm; Venezue- la, Yaracuy, Rio Tupe, N of Aroa. Creagrutus lepidus, USNM 325045, 2, 33.0-40.3 mm, paratypes; Venezuela, Yaracuy, Rio Aroa basin. Creagrutus machadoi, MCNG 41717, 1, 44.4 mm; Venezuela, Bolivar, Cano Yumucukena. Creagrutus magdalenae, USNM 357733, 8, 16.8^5.8 mm; Colombia, Cundinamarca, Apulo. Creagrutus magoi, USNM 353863, 1,42.2 mm, paratype; Ven- ezuela, Bolivar, Rio Chaviripa. Creagrutus manu, USNM 326903, 1, 39.3 mm, paratype; Peru, Madre de Dios, Parque Nacional Manu. Creagrutus maracaiboensis, USNM 121532, 1, 19.0 mm, paratype of Creagrutops maracaiboensis; Venezuela, Lago Maracaibo basin, Rio Negro. MCNG 126, 2, 22.3-25.0 mm; Venezuela, Zulia, Cano La Raza. USNM 357791, 2, 23.0-23.7 mm; Venezuela, Zulia, Rio Negro. NUMBER 613 Creagrutus maxillaris, ANSP 161235, 1, 39.8 mm; Venezuela, Amazonas, Rio Ventuari, above confluence with Rio Orinoco. CAS 151036, 1 (AR), 37.1 mm; Venezuela, Amazonas, Rio Orinoco. Creagrutus melanzonus, ROM 70239, 1, 26.4 mm; Guyana, Mazuruni-Potaro, Mazuruni River. MCNG 1031, 1, 28.5 mm; Venezuela, Bolivar, Rio Cuyuni basin. Creagrutus melasma, MBUCV V-21257, 2, 32.0-32.2 mm, paratypes; USNM 326056, 2, 32.0-32.2 mm, paratypes; Ven- ezuela, Aragua, Rio Tuy basin. Creagrutus menezesi, MZUSP 4970, 2, 23.4-26.5 mm; Brazil, Maranhao, Rio Tocantins, Estreito. USNM 292229, 2, 57.1-61.8 mm, paratypes; Brazil, Goias, Rio Tocantins basin, Ribeirao Paranoa do Meio. Creagrutus meridionalis, USNM 341363, 2, 45.2^8.5 mm, paratypes; MZUSP 50547, 50.9 mm, paratype; Brazil, Mato Grosso, Ribeirao Chiqueirao. Creagrutus mucipu, USNM 350449, 1, 41.4 mm, paratype; Brazil, Goias, Municipio de Minacu/Colinas do Sul, Rio To- cantins. Creagrutus muelleri, USNM 340984, 2, 45.4-53.3 mm; Ecua- dor, Pastaza, Rio Pastaza. USNM 340983, 1, 75.9 mm; Ecua- dor, Zamora-Chincipe, Rio Zamora. Creagrutus nigrostigmatus, ICNMHN 989, 1, 19.8 mm; Co- lombia, Sucre, Tuloviejo, Cano Pechlin. Creagrutus occidaneus, USNM 326920, 2, 56.0-59.1 mm; Peru, Madre de Dios, Parque Nacional Manu. Creagrutus ortegai, USNM 340972, 2, 49.0-53.1 mm, paratypes; Peru, San Martin, Rio Cainarachi. Creagrutus ouranonastes, USNM 340988, 1, 52.2 mm, paratype; Peru, Apurimac, Aymaraes, Rio Chalhuanca. Creagrutus paraguayensis, USNM 340958, 2, 48.9-52.5 mm; Paraguay, Alto Paraguay, 5 km N of Bahia Negra. Creagrutus paralacus, USNM 121502, 2, 50.7-59.0 mm; Ven- ezuela, Tachira, Rio Mototan. USNM 121505, 1, 51.3 mm; Venezuela, Merida, Rio Gonzalez at La Gonzalez. Creagrutus pearsoni, USNM 263951, 2, 27.6-30.4 mm; Peru, Madre de Dios, Rio Tambopata system. Creagrutus peruanus, USNM 340981, 2, 41.1^4.2 mm; Peru, Junin, Rio Mijandari. USNM 340979,2,47.0-50.1 mm; Peru, Junin, Chanchamayo, Rio Chanchamayo, Mijandari. Creagrutus petilus, USNM 340957, 2, 44.0-44.4 mm, paratypes; Brazil, Rondonia, Rio Marco Rondon. Creagrutus phasma, MCNG 21491, 1, 51.4 mm; Venezuela, Bolivar, Salto de Icutu, Rio Caura system. MCNG 17961, 2, 40.5-46.2 mm; Venezuela, Apure, Rio Cinaruco. Creagrutus pila, USNM 341367, 2, 46.7-51.3 mm, paratypes; Peru, Ucayali, Rio Tahuayo. Creagrutus provenzanoi, MBUCV V-14547, 2, 46.4-47.1 mm; Venezuela, Bolivar, Rio Cataniapo. Creagrutus runa, MZUSP 29890, 1, 41.5 mm; Brazil, Amazo- nas, Rio Negro, Cachoeira de Sao Gabriel. MCNG 23311, 1, 56.3 mm; Venezuela, Amazonas, upper Rio Negro. Creagrutus saxatilis, USNM 341480, 1, 47.6 mm, paratype; Brazil, Distrito Federal, Rio Maranhao. Creagrutus seductus, USNM 342231, 1, 60.8 mm, paratype; Brazil, Mato Grosso, upper Rio Araguaia basin, Municipio de Barra do Garcas. Creagrutus taphorni, USNM 357730, 2, 50.7-51.1 mm; Vene- zuela, Miranda, El Amoladero, Rio Guiare. USNM 357729, 3, 40.7-62.7 mm; Venezuela, Rio Guaire, near Caracas. Creagrutus ungulus, USNM 303066, 3, 55.0-53.5 mm, paratypes; Peru, Madre de Dios, Rio Alto Madre de Dios. Creagrutus vexillapinnus, USNM 341361, 1, 42.0 mm; Brazil, Amazonas, Rio Negro, above Barcelos. Creagrutus zephyrus, ANSP 161236, 2, 25.4-27.5 mm; Vene- zuela, Amazonas, Rio Casiquiare. Piabina argentea, USNM 311172, 1, 50.2 mm; Brazil, Minas Gerais, Corrego de Juliao, N of Lagoa Santa. USNM 292220, 3, 33.8-59.2 mm; Brazil, Distrito Federal, Ribeirao Santana. The following outgroup characiforms were the basis for the comparisons in this study. Alestidae Alestes lateralis Boulenger, USNM 310101, 1, 75.0 mm; Botswana, Xugana. Alestes longipinnis (Gunther), USNM 285665, 3, 44.7-50.5 mm; Togo, Togble-Kope. Characidae Bracychalcinus copei (Steindachner), USNM 263862, 2, 32.5-36.8 mm; Peru, Madre de Dios, tributary stream to Rio Madre de Dios. Brycon falcatus Muller and Troschel, USNM 226161, 2, 71.3-78.2 mm; Suriname, Corantijn River. Bryconamericus brevirostris Gunther, USNM 311293, 2, 50.5- 53.4 mm; USNM 311329, 12, 35.0-36.7 mm; Ecuador, Los Rios, Rio Vinces. Bryconamericus hyphessus Eigenmann, USNM 225745, 2, 30.4-33.5 mm; Suriname, Nickerie District, Mataway Creek. Bryconamericus iheringi Boulenger, USNM 285884, 2, 29.1-54.1 mm; Brazil, Rio Grande do Sul, Arroio Garupa. Bryconamericus stramineus Eigenmann, USNM 232201, 1, 41.5 mm; Paraguay, Amambay, Rio Aquidaban. USNM 285959, 2, 33.4-39.6 mm; Brazil, Rio Grande do Sul, Rio Garupa. Bryconops affinis (Gunther), USNM 225968, 3,42.8^8.5 mm; Suriname, Nickerie District, Corantijn River. Chalceus macrolepidotus Cuvier, USNM 231547, 1, 115 mm; aquarium specimen. Cheirodon affinis (Meek and Hildebrand), USNM 209483, 2, 29.5-33.3 mm; Panama, Rio Santa Maria. Gymnocharacinus bergi Steindachner, USNM 313878, 3, 34.5-44.3 mm; Argentina, Provincia Rio Negro, Estancia "El Rincon." 8 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY Hemibrycon dariensis Meek and Hildebrand, USNM 293245, 2,44.0-57.4 mm; Panama, Darien, Rio Pucuro. Hemibrycon metae Myers, USNM 228563, 2, 43.3-48.6 mm; Venezuela, Surce, Clavellino Reservoir. Hemibrycon sp., USNM 317772, 2, 44.0-59.2 mm; Peru, Madre de Dios, Alto Rio Madre de Dios basin. Hyphessobrycon sp., USNM 345533, 2, 30.0-32.4 mm; Vene- zuela, Amazonas, Rio Negro basin, Carlo Urami. Hyphessobrycon sp., USNM 345532, 4, 22.3-32.8 mm; Vene- zuela, Amazonas, Rio Negro basin, Cano Tremblador. Lignobrycon myersi (Miranda-Ribeiro), USNM 304497, 1, 84.8 mm; Brazil, Bahia, Rio do Braco. Moenkhausia cotinho Eigenmann, USNM 272424, 3, 35.9- 38.9 mm; Venezuela, Amazonas, upper Rio Negro basin. Odontostilbe paraguayensis Eigenmann and Kennedy, USNM 181422, 2, 30.7-31.6 mm; Paraguay, Rio Paraguay, Isla Mar- garita. Piabarchus analis (Eigenmann), USNM 326384, 2, 30.6-30.9 mm; Brazil, Mato Grosso, Rio Paraguai, near Capo Grande. Piabarchus torrenticola Mahnert and Gery, USNM 326536, 5, 24.3-26.7 mm; Brazil, Mato Grosso, Rio Paraguai, 48 km from Porto Esperidiao. Piabucus melanostomus Holmberg, USNM 310907, 2, 61.5- 62.8 mm; Brazil, Amazonas, Rio Madeira basin, 5 km E of Humaita. Poptella compressa (Gunther), USNM 300994, 2, 50.5-57.6 mm; Venezuela, Delta Amacuro, Rio Orinoco basin. Roeboides qffinis (Gunther), USNM 308781,6,28.0-47.7 mm; Brazil, Amazonas, Rio Amazonas, Ilha de Marchantaria. Roeboides occidental Meek and Hildebrand, USNM 293236, 2,49.9—59.1 mm; Panama, Darien, Rio San Antonio basin. Triportheus angulatus (Spix), USNM 270343, 2, 63.2-74.6 mm; Venezuela, Bolivar, Rio Orinoco. Virilia pabrensis (Roman), USNM 326209, 2, 33.4-37.5 mm; Ghana, Dayi River. Crenuchidae Ammocryptocharax elegans Weitzman and Kanasawa, USNM 210691, 3, 36.3-39.8 mm; Brazil, Amazonas, Brazilian-Bo- livian border region. Characidium sp., USNM 100957, 2, 20.2-33.3 mm; Brazil, Minas Gerais, Rio Sao Francisco, Piraporinha. Distichodontidae Nannocharax intermedius Boulenger, USNM 231555, 2, 50.7-63.4 mm; West Africa. Nannocharax seyboldi Schultz, USNM 193921, 1, 42.1 mm; Liberia, Gbarnga District, tributaries of St. John's River. Paradistichodus dimidiatus Pellegrin, USNM 231556, 2, 45.6-47.3 mm; Ghana, Dayi River. Xenocharax spilurus Gunther, USNM 227693, 1, 89.3 mm; Gabon, Lac Ezanga. Hemiodontidae Anodus elongatus Spix, USNM 231550, 1, 120 mm; Peru, Loreto, Rio Ucayali. Argonectes scapularis Bohlke and Myers, USNM 243224, 1, 125 mm; Brazil, Amazonas, Rio Janauperi. Bivibranchia velox Vari and Goulding, USNM 268345, 1, 109 mm; Brazil, Para, Rio Tocantins. Hemiodus ocellatus Vari, USNM 225593,1,99.6 mm SL; Suri- name, Nickerie District, Corantijn River. Parodontidae Apareidon qffinis (Steindachner), USNM 176007, 1, 89.0 mm; Argentina, Rio Parana, Santa Fe. Apareidon dariensis (Meek and Hildebrand), USNM 345548, 1, 80.5 mm; Colombia, Rio Salado. Parodon suborbitalis Valenciennes, USNM 231552, 2, 55.0- 58.1 mm; Colombia, Rio Salado. Saccodon dariensis (Meek and Hildebrand), USNM 208505,1, 73.3 mm; Panama, Rio Membrillo. TERMINOLOGY.—Osteological terminology is that used by Weitzman (1962) with the following modifications discussed by Vari (1989). Vomer is substituted for prevomer and interca- lar for opisthotic as in most recent publications dealing with characiforms. The use of epioccipital rather than epiotic fol- lows Patterson (1975), and the use of the anguloarticular for ar- ticular and retroarticular instead of angular follows Nelson (1973). Use of posterior ceratohyal for epihyal and anterior cer- atohyal for ceratohyal follows Nelson (1969), and mesethmoid rather than ethmoid follows Fink and Fink (1981). The concepts of characiform families used in this paper are those of Greenwood et al. (1966) with several modifications. The family Ichthyboridae of Greenwood et al. (1966) is consid- ered to be a subunit of the Distichodontidae following Vari (1979), and the Cynodontidae of those authors is recognized as a tribe within the Characidae, in keeping with the results of Howes (1976), Toledo-Piza (1997), and Lucena and Menezes (1998). Anodus Agassiz and Eigenmannina Fowler, assigned to the Curimatidae by Greenwood et al. (1966), are rather placed in the Hemiodontidae as proposed by Roberts (1974) and Langeani (1996, 1998). The use of Crenuchidae for taxa previ- ously placed within the Characidae follows Buckup (1998). Old World taxa assigned to the Characidae according to Green- wood et al. (1966) are referred to herein as the Alestidae as proposed by Buckup (1998) and as discussed by Vari and Or- tega (1999). ACKNOWLEDGMENTS The completion of a large project such as this one is only possible with the assistance of numerous individuals and insti- tutions who arranged for the loan and exchange of specimens, provided diverse types of information, hospitality during visits, NUMBER 613 and the myriad other types of assistance. We thank Gareth J. Nelson, Melanie L.J. Stiassny, and M. Norma Feinberg (AMNH); Scott A. Schaefer and William G. Saul (ANSP); Gordon J. Howes and Darrell J. Siebert (BMNH); Tomio Iwa- moto, David Catania, and Carl J. Ferraris, Jr. (CAS); Jamie Sarmiento (CBF); Barry Chernoff, Mary Anne Rogers, and Kevin Swagle (FMNH); Plutarco Cala (ICNMHN); Paulo Ce- sar Venere (ICLMA); Lawrence M. Page, Kevin S. Cummings, Christine Mayer, Michael E. Retzer, and Mark Sabaj (INHS); Edward O. Wiley and Kate Shaw (KU); Robert Lavenberg and Jeffrey Siegel (LACM); Antonio Machado-Allison and Fran- cisco Provenzano (MBUCV); Donald C. Taphorn (MCNG); Carlos A. Lucena, Luiz R. Malabarba, and Roberto E. Reis (MCP); Karsten E. Hartel (MCZ); Ramiro Barriga (MEPN); Volker Mahnert and Sonia Muller (MHNG); Guy Duhamel and Martine Desoutter (MNHN); Carlos Lasso (MHNLS); Mirta Miranda and Dario Mandelburger (MNHNP); Paulo A. Buckup and Hugo R.S. Santos (MNRJ); Axel Zarske (MTD); Hernan Ortega and the late Fonchii Chang (MUSM); Naercio A. Men- ezes, Heraldo A. Britski, Jos£ L. de Figueiredo, Osvaldo T. Oy- akawa, and Mdrio C.C. de Pinna (MZUSP); Barbara Herzig (NMW); Martien J.P. van Oijen (NNM); Sven O. Kullander and Erik Ahlander (NRM); Erling Holm, Richard Winterbot- tom, and Karen Ditz (ROM); George Burgess and John Matter (UF); Douglas W. Nelson and William L. Fink (UMMZ); Han Nijssen and Isaac Isbriicker (ZMA); Horst Wilkens (ZMH); Jorgen Nielsen (ZMUC); Maurice Kottelat (formerly ZSM); Luis A. Fernandez (Fundacion Miguel Lillo, Argentina); and Cristiano Morreira (Universidade Federal do Rio de Janeiro). Research, collecting efforts, and museum studies in South America associated with this paper were funded by the Neotro- pical Lowland Research Program of the International Environ- mental Sciences Program of the Smithsonian Institution and the Research Opportunity Fund and Department of Vertebrate Zoology of the National Museum of Natural History. Support to the junior author was provided by a Natural Sciences and Engineering Research Council of Canada Postdoctoral Fellow- ship, a Tilton Fellowship at CAS, the College of Charleston, and Short-Term Visitor Grants from the Office of Fellowships and Grants, Smithsonian Institution. Research space and facili- ties for the junior author were provided by the Centre for Biodiversity and Conservation Biology, ROM. Many of the specimens reported on in this paper that originated in Bolivar and Amazonas states of Venezuela were collected under a CONICET (Consejo Nacional de Investigaciones Cientificas y Tecnologicas) grant to Antonio Machado-Allison (MBUCV). Photographs of specimens were prepared by T. Britt Gris- wold (NMNH). Technical support at NMNH was provided by Jeffrey M. Clayton, Lisa F. Palmer, David G. Smith, Shirleen Smith, and in particular Sandra J. Raredon who tirelessly radio- graphed numerous specimens and in many other ways assisted with the project. David Steere, Smithsonian Institution Librar- ies helped us locate many obscure publications. Karen Ditz provided technical support at ROM. The distribution maps are based on a map of South America prepared by Marilyn Weitz- man (NMNH). Ian Watson, Natural Resources Institute, pro- vided information on Ecuadorian localities at which he col- lected various Creagrutus samples. Erling Holm (ROM) and Hans-Georg Evers provided color transparencies of live speci- mens that served as the basis of some life coloration descrip- tions. The Portuguese translation of the Resumo was provided by Luiz R. Malabarba (MCP). This paper was improved by the very useful comments and suggestions of Carl J. Ferraris, Jr. (CAS), Michael E. Retzer (INHS), and Stanley H. Weitzman (USNM) all of whom tirelessly read through earlier drafts of the manuscript. The final version benefitted from the careful copy editing and composition of the paper by Jack Korytowski and Diane Tyler, Smithsonian Institution Press. Character Description and Analysis Vari and Harold (1998) proposed that Piabina is the sister group to Creagrutus, but they did not delve into the question of intrageneric relationships within the latter genus. We herein discuss a more extensive series of characters relevant to the hy- pothesis of a sister-group relationship between Creagrutus and Piabina along with synapomorphies that diagnose both genera. We also advance a hypothesis of relationships within Creagru- tus. Proposal of a hypothesis of phylogenetic relationships within Creagrutus is complicated by the absence of a rigorous hypothesis of the more inclusive relationships of that genus and Piabina. Although various authors (e.g., Gery, 1966:281) cited similarities of Creagrutus to other characid genera, these con- jectures were derived from the joint possession of characters of undetermined polarity rather than identified synapomorphies. Creagrutus, Piabina, Creagrudite, and Creagrutops do, how- ever, lack the supraorbital bone, which is an independent ossifi- cation of the lateral surface of the skull primitively present an- terodorsal or dorsal of the orbit. The derived absence of this ossification is diagnostic of the subfamily Tetragonopterinae within the Characidae (Weitzman and Malabarba, 1998:163), although it also is absent in the characid subfamilies Agoniati- nae, Aphyocharacinae, Characinae, Cheirodontinae, Glandulo- caudinae, Iguanodectinae, Paragoniatinae, Rhoadsinae, and Stethaprioninae. Creagrutus and Piabina, however, lack the sy- napomorphies for the Characininae (Lucena, 1998), Cheiro- dontinae (Malabarba, 1998), Glandulocaudinae (Weitzman and Menezes, 1998), Iguanodectinae (Vari, 1977), and Stethaprion- inae (Reis, 1989) and similarly lack the distinctive specializa- tions of the Agoniatinae, Aphyocharacinae, Paragoniatinae, and Rhoadsinae. As a consequence, we center our comparisons of Creagrutus and Piabina on the Tetragonopterinae. In the ab- sence of evidence supporting the monophyly of the Tet- ragonopterinae, our outgroup comparisons were expanded to other characids and in some instances to noncharacid characi- forms. General statements about characters in examined 10 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY TABLE 2.—Character matrix of 57 characters for the species of Creagmtus and Piabina in the sense of this study. Character numbers correspond to those in the text. Lack of material precluded the inclusion of C. molinus, C. planquettei. C. veruina, and C. xiphos. Creagrutus affinis amoenus anary atratus atrisignum barrigai beni bolivari brevipinnis britskii calai caucanus changae cochui cracenlis crenatus ephippiatus figueiredoi flavescens gephyrus gracilis gyrospilus hildebrandi holnti hysginus ignotus kunturus lasso i lepidus machadoi magdalenae magoi manu maracaiboensis maxillaris melanzonus melasma menezesi meridionalis mucipu muelleri nigrostigmatus occidaneus ortegai ouranonasles Paraguay ens is paralacus pearsoni peruanus petilus phasma pila provenzanoi runa saxatilis seductus laphorni ungulus vexillapinnus zephyrus Piabina argentea 1-10 1110110111 1110110211 1110110111 1110110111 1110110111 1110110111 1110110111 1110110111 1110110111 1110110111 1110110111 1110110111 1110110111 1110110111 0??1011111 1110110111 1110110111 1110110111 1110110111 0110111111 1110110111 1110110111 1110110111 1110110111 1110110111 1110110111 1110110211 1110110111 1110110111 1110110111 1110110111 1110110111 1110110111 1000110101 0??1011111 I0001I0111 1110110111 1110110111 1110110111 1110110111 1000110101 1000110101 11101101] 1 1110110111 1000110101 1110110111 1110110111 1110110111 1000110101 1110110111 1110110111 1110110111 1110110111 1000110111 1110110111 1110110111 1110110111 1110110111 1110110111 1110110111 1000000001 11-20 1110000010 1110000010 1110000010 1110000010 1110000010 1110000010 1110000010 1110000010 1110000010 1110000010 1110000010 1110000010 1110000010 1110000010 1101101111 1110000010 1110000010 1110000010 1110000010 1101101110 1110000010 1110000010 1110000010 1110000010 1110000010 1110000010 1110000010 1110000010 1110000010 1110000010 1110000010 1110000010 1110000010 1110000010 1101101111 1110010010 1110000010 1110000010 1110000010 1110000010 1110000010 1110000010 1110000010 1110000010 1110000010 1110000010 1110000010 1110000010 1110000010 1110000010 1110010010 1110000010 1110000010 1110010010 1110000010 1110000010 1110000010 1110000010 1110000010 1110000010 0010000000 Character 21-30 1100111011 1100111011 1100111011 1100111011 1100111011 1100111011 1100111011 1100111011 1100111011 1100111011 1100111011 1100111011 1100111011 1100111011 1100110011 1100111011 1100111011 1100111011 1100111011 1000110011 1100111011 1101111011 1100111011 1100111011 1100111011 1100111011 1100111011 1101111011 1100011110 1100111011 1100111011 1100111011 1100111011 111011100? 1100110011 1100111011 1100111110 1100111011 1100111011 0100111011 1100111011 1110111011 1100111011 1100111011 1100111011 1100111011 1100111011 1100111011 1100111011 1100111011 1100111011 1100111011 1100111011 1100111011 1100111011 1100111011 1100111011 1100111011 1100111011 1110111011 1000001000 31-40 0011100000 0010110101 0011100100 0110110101 0011101101 0110100100 0011110100 0110110100 0011110101 0010110101 0010100101 0011100101 0011110101 0010111100 0010000100 0010100100 0010110101 0010110100 0010100101 0110000100 0110100100 0010110101 0011100101 0011110101 0010110100 0010100100 0010110101 0010100101 0010111100 0110110100 0110110100 0010100101 0011110101 0000101110 0010000100 0010100100 0010100100 0010110100 0010100000 0110110100 0010101101 0000100110 0010110101 0011110100 0010101101 0010110101 0110110101 0011100000 0010100101 0010110100 0010100100 0111101101 0010100100 0011100100 0011100100 0110110101 0110110101 0010110101 0110110100 0111100100 1000100000 41-50 1110001110 0110001110 1110001010 1110101110 1110101010 1110001010 0110001010 1110101110 1110001010 1110101010 1110001010 0110001010 1110001110 0110101010 0110011010 1110001111 1110001110 0110101010 1110001010 0110001110 1110101010 1111001110 1110001011 1110001010 0111001110 1110001010 1110001110 0110001110 0110001111 1110001110 1110001010 1110001110 1110001010 1110001111 0110011010 1100001010 1110001011 1110001010 1110101110 0110001110 1110001010 1110001110 0110001010 1110001110 1110001110 1110101110 1111001110 1100001010 1110001011 0110001111 1110001010 0110001010 0110001110 1110001010 0110001010 0110001010 1110001110 0110001011 0110001010 0100001100 0110000100 51-57 0000100 0001100 0000100 0000101 0010100 0000100 0000100 0000001 0000100 0000100 0000100 0000100 0000100 0010100 0100100 0000100 0000100 0000100 0000100 0000100 0000100 0000100 0000100 0000100 0000100 0000100 0001100 0001000 0000100 0000000 0000100 0000101 0000100 1000110 0100000 0000000 0000100 0000100 0000100 0000000 0000100 1000110 0000100 0000100 0000100 0000100 0000100 0000100 0000100 0000000 0000000 0000100 0000100 0000000 0000000 0000100 0000100 0100100 0000100 0000000 0000100 NUMBER 613 11 characiform outgroups encompass diverse assemblages, in- cluding when appropriate Xenocharax, the hypothesized most generalized characiform (Fink and Fink, 1981) and other mem- bers of the basal clade formed by the Citharinidae and Distich- odontidae. The character numbers in the text correspond to those in Ta- ble 2. Synapomorphy numbers in the "Phylogenetic Recon- struction" sections correspond to that numbering system. Auta- pomorphic characters are not included in Table 2, are not utilized in the computer analyses, and are not numbered, but they are cited in the diagnosis for the species, if those species are treated in this paper. PHYLOGENETIC POSITIONS OF Creagrudite, Creagrutops, AND Piabina.—A subset of the derived characters discussed by Vari and Harold (1998) and in the following sections are con- gruent with the hypothesis that Piabina argentea is the sister lineage to Creagrutus. This conclusion differs from traditional taxonomic concepts under which Piabina argentea was aligned with a species herein placed in Creagrutus (C. pearsoni of this study) with which it shares a higher number of branched anal- fin rays than is typical for most Creagrutus species. Our recog- nition of a separate Piabina also runs counter to recent taxo- nomic practice (e.g., Mahnert and Gery, 1988) under which Pi- abina was considered a junior synonym of Creagrutus. Piabina (sensu stricto), although outside the scope of a revisionary and intrageneric phylogenetic study of Creagrutus as diagnosed herein, is, as the sister group to Creagrutus, significant for pur- poses of the polarization of characters within the latter genus. Although Piabina lies outside the scope of the originally en- visioned revisionary study of Creagrutus, autapomorphies for Piabina have not been previously identified, nor has its single contained species, P. argentea Reinhardt, been analyzed across its geographic range. We consequently expanded our revision- ary study to include a redescription of Piabina argentea and broadened our phylogenetic analysis to identify autapomor- phies for that species. Prior to the synonymy of Piabina into Creagrutus (Mahnert and Gery, 1988), Piabina included a sec- ond species, Piabina beni Pearson (1924), the Creagrutus pearsoni Mahnert and Gery (1988) of this study (see comments under "Remarks" for the latter species). The results of the phy- logenetic analysis indicate that Creagrutus pearsoni, the former Piabina beni, is more closely related to components of Creagrutus deeply nested within the phylogeny of that genus than it is to Piabina argentea. Myers (1927:117) and Schultz (1944:327) distinguished Cre- agrudite and Creagrutops, respectively, from Creagrutus based on modifications of the lateral line and dentition. The most par- simonious hypothesis of phylogenetic relationships for the as- semblage consisting of Creagrutus, Creagrudite, and Creagru- tops indicates that the diagnostic features proposed for Creagrudite and Creagrutops are derived, but that each genus constitutes a specialized lineage within what would be a non- monophyletic Creagrutus if Creagrudite and Creagrutops con- tinue to be recognized. Thus, Creagrudite and Creagrutops are considered synonyms of Creagrutus in order to make the latter genus monophyletic. From this point on, Creagrutus is used in this broader sense, including the species formerly placed in Creagrudite and Creagrutops. GENERIC ASSIGNMENT OF Creagrutus molinus, C. plan- quettei, C. veruina, AND C. xiphos.—Three species described as new in this paper are known only from a holotype (C. moli- nus) or small type series (C. veruina, C. xiphos). Creagrutus planquettei Gery and Renno, 1989, in turn, was described from a limited type series and evidently has not been collected sub- sequently. Such restricted samples preclude clearing and stain- ing of specimens of these four species for detailed studies of their osteology. The four species, nonetheless, share the exter- nally obvious characters synapomorphic for Creagrutus or sub- units of that genus (see "Phylogenetic Position of C. molinus, C. planquettei, C. veruina, and C. xiphos" below). Given that the vast majority of the characters utilized in the phylogenetic analysis can only be examined in cleared and stained speci- mens, we exclude these species from the matrix rather than rep- resenting them primarily as missing data. Resolution of the ex- act intrageneric phylogenetic relationships of these species must await the collection of additional material. The discussion of phylogenetically informative characters is arranged in terms of various major body systems, with diverse residual characters discussed under "Miscellaneous." JAWS AND ASSOCIATED LIGAMENTS PREMAXILLA.—The premaxilla in Piabina argentea and most Creagrutus species approximates an irregular triangle when examined from a ventral view (Figures 1, 2). In these taxa the premaxillary teeth are large both with respect to the size of the upper jaw and relative to the dentigerous surface of the premaxilla. As a consequence, the dentition covers an un- usually high proportion of the ventral surface of the premaxilla relative to the condition in most characids. Although an ap- proximately triangular dentigerous surface on the premaxilla also occurs in some species of Brycon Miiller and Troschel (e.g., B. dentex Giinther and B. oligolepis Regan; see Howes, 1982, figs. 15, 21), the premaxillary dentition in these Brycon species is much more dispersed than the densely packed teeth typical of Piabina and Creagrutus species. Other Brycon spe- cies have more elongate premaxillae and much different ar- rangements of premaxillary dentition (e.g., B. devillei Castel- nau and B. falcatus Miiller and Troschel; see Howes, 1982, figs. 16, 18). Although Brycon is undiagnosed on the basis of synapomorphies, it has been defined by a series of unpolarized characters (Howes, 1982:1), which may either diagnose a natu- ral assemblage or more closely align it with genera such as Tri- portheus Cope, Chalceus Cuvier, or Moojenichthys Miranda- Ribeiro (see Castro and Vari, 1990:532; Malabarba, 1998:76). Furthermore, studies on a subset of characiform taxa (Buckup, 1998:134) indicated that Brycon is not closely related to Tet- ragonopterus Cuvier, the type genus of the Tetragonopterinae that shares with Creagrutus and Piabina the apomorphic loss of the supraorbital. This evidence supports a hypothesis that the roughly triangular dentigerous surface of the premaxilla in Bry- con species, such as B. dentex and B. oligolepis, was achieved independently of that in Piabina and Creagrutus. Given its re- 12 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY B FIGURE 1.—Premaxilla and premaxillary dentition in Creagnitus muelleri, USNM 340983, 75.9 mm SL; left side, ventral view, anterior at top. (Abbrevia- tions: A, triangular cluster of teeth; B, primary premaxillary tooth series, and C, single lateral tooth.) stricted occurrence among characiforms and its absence in basal characiform taxa, such as the Distichodontidae and Cith- arinidae, the triangular dentigerous surface of the premaxilla in Piabina and Creagnitus is considered to be derived. The form of the dentigerous surface of the premaxilla typical for most members of Creagnitus demonstrates only minor in- trageneric variations other than in C. cracentis, C. gephyrus, and C. maxillaris. These three species, rather than having an approximately triangular premaxilla, have a posterolaterally elongate, roughly rectangular premaxillae in a ventral view (Figures 3, 4). The ventral surface of the premaxilla in these three species approximates that in many characid outgroups (e.g., Paracheirodon innesi Myers; see Weitzman and Fink, 1983, fig. 23). Nonetheless, such a posteroventrally elongate premaxilla in these three species is considered to be indepen- dently derived under the overall most parsimonious hypothesis of phylogenetic relationships in the Piabina-Creagrutus assem- blage under which the clade formed by C. cracentis, C. ge- phyrus, and C. maxillaris is deeply nested within the phylog- eny for Creagnitus (Figure 17). CHARACTER 1. State 0: Dentigerous surface of premaxilla longitudinally elongate from ventral view. State 1: Dentigerous surface of premaxilla triangular from ventral view. FIGURE 2.—Premaxilla and premaxillary dentition in Creagrutus hysginus, USNM 326055,41.3 mm SL; left side, ventral view, anterior at top. (Abbrevia- tions: A, triangular cluster of teeth; B, primary tooth row; and C, single lateral tooth.) PREMAXILLARY TEETH.—Diverse descriptive schemes (e.g., Howes, 1982, for Brycori) have been proposed to resolve the homology of components of the premaxillary dentition among various genera in the families Characidae and Alestidae, which together form the major portion of the Characidae of many pre- vious authors. As noted under "Premaxillary Dentition in Crea- grutus and Piabina," below, these alternative descriptive schemes failed to unequivocally homologize individual teeth or groups of teeth across the major taxonomic groups in these families. Such difficulties are understandable given the diver- sity of tooth arrangement patterns across the Characidae and Alestidae. Three general patterns of premaxillary teeth, each with less pronounced internal variation among included species, occur among the species of Creagrutus, one of which also is common to the first outgroup, Piabina (Figures 1-4). Perusal of these tooth patterns demonstrates the difficulties inherent in homolo- gizing individual teeth even within this limited subunit of the Tetragonopterinae, let alone in addressing the question of tooth homologies across the rest of that subfamily or the entire Charac- idae. For the purposes of this study we discuss the premaxillary dentition in Creagrutus and Piabina in terms of the three major components found in all but a few Creagrutus species. One landmark constant to the three patterns of premaxillary dentition in Piabina and Creagrutus is the large tricuspidate tooth situated at the posterior margin of the premaxillary tooth NUMBER 613 13 FIGURE 3.—Premaxilla and premaxillary dentition in Creagrutus gephyrus, USNM 340953, 47.4 mm SL; left side, ventral view, anterior at top. (Abbrevia- tions: A, triangular cluster of teeth; B, primary tooth tow; and C, single lateral tooth.) series (Figures 1, 2). That tooth and two other proportionally large teeth, one medial to it and the second anteromedial to it, form a distinct triangular cluster (hereafter termed the triad) sit- uated on the posteromedial portion of the dentigerous surface of the premaxilla. This triad is the first major component of the premaxillary dentition in these genera (note: triad modified in Creagrutus cracentis and C. maxillaris, see discussion below). Located anterior and lateral to the triad is a series of four to seven, somewhat to distinctly smaller, teeth whose arrange- ment ranges from a nearly straight line, through an arch, to a sigmoid pattern. Regardless of their exact arrangement or the number of teeth, these four to seven teeth form an identifiable unit herein termed the primary premaxillary tooth series, the second major component of the premaxillary dentition. Lateral to the third to fifth teeth of the primary series (relative position a function of the number teeth in the primary series) is a single, typically tricuspidate, tooth, termed herein the lateral tooth, which is the third component of the pattern (this tooth is absent in a small number of Creagrutus species; see discussion be- low). Piabina argentea and seven Creagrutus species (C. maracai- boensis, C. melanzonus, C. muelleri, C. nigrostigmatus, C. ou- ranonastes, C. peruanus, C. runa) have the gap between the first and second teeth in the primary tooth series distinctly wider than the spaces between the remaining teeth of the series (Figure 1). The separation of those two teeth in these species also is much more pronounced than the gap between homolo- gous teeth in all other Creagrutus species, other than C. cra- centis and C. maxillaris, which have highly modified premaxil- lary dentition. The extent of the gap in Piabina argentea and FIGURE 4.—Premaxilla and premaxillary dentition in Creagrutus maxillaris. ANSP 161235, 39.8 mm SL; left side, ventral view, anterior at top. the seven cited Creagrutus species approximates the separation between these teeth in other tetragonopterines, and its presence is therefore considered the primitive condition. The primary tooth series found in all Creagrutus species, other than for C. maracaiboensis, C. melanzonus, C muelleri, C. nigrostigma- tus, C. ouranonastes, C. peruanus, and C. runa, differs from the pattern in those seven species in having contact, or near contact (Figure 2), between the two anterior teeth of the pri- mary series rather than a distinct gap in that region, which is a derived condition. CHARACTER 2. State 0: Primary premaxillary tooth series with gap between first and second teeth distinctly greater than spaces between the remaining teeth in series. State 1: Primary premaxillary tooth series with gap between first and second teeth comparable to those between remaining teeth in that se- ries. Piabina argentea and seven Creagrutus species (C. maracai- boensis, C. melanzonus, C. muelleri, C. nigrostigmatus, C. ou- ranonastes, C. peruanus, C. runa) have the triad of premaxil- lary teeth positioned immediately posterior to the primary premaxillary series (Figure 1). The anterior position of the triad in conjunction with the distinct separation of the first and sec- ond teeth of the primary series results in the anterior tooth of the triad being nestled, to varying degrees, in the gap between the first and second teeth. This proximity between the primary tooth row and the triad and the forward location of the anterior tooth of the triad in these eight species led some authors (e.g., Gery and Renno, 1989:4) to interpret the premaxillary dentition in this assemblage as consisting of two irregular tooth rows, a pattern common to various characids and alestids. Although such a description could be applied to Piabina and the seven Creagrutus species, we prefer to apply the three component de- scription outlined above to these eight species in order to as- sure consistency in all descriptions across Piabina and Crea- grutus. In all Creagrutus species, other than C. maracaiboensis, C melanzonus, C. muelleri, C. nigrostigmatus, C. ouranonastes, 14 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY C. peruanus, and C. runa, the triad of teeth is positioned more posteriorly relative to the primary tooth series than it is in the pattern described above for Piabina argentea and these Crea- grutus species (see also below concerning C cracentis and C. maxillaris). As a consequence, the anterior tooth of the triad is positioned distinctly posterior of the main axis through the pri- mary tooth series, being either situated behind the transverse line through the second tooth or posterior to the transverse line extending through the gap between the second and third tooth of the primary series (e.g., C. planquettei, Gery and Renno, 1998, fig. 3). This tooth arrangement pattern is unique to this assemblage of Creagrutus species among examined characi- forms and is thus considered to be derived. As noted above, the highly modified form of the premaxilla and its tooth arrangement in Creagrutus cracentis and C. max- illaris constitute the third pattern of premaxillary dentition within Creagrutus (Figure 4). The magnitude of the alterations in these two species renders direct comparisons of their tooth patterns and premaxillary form with the conditions in conge- ners problematic. An evaluation of the homologies of the pre- maxillary dentition in C. cracentis and C maxillaris with those in other Creagrutus species is, however, facilitated by an ex- amination of the tooth arrangement in C. gephyrus (Figure 3). The latter species has a premaxillary dentition arrangement in- termediate between that typical of Creagrutus species (Figures 1,2) and the tooth pattern found in C. cracentis and C. maxil- laris (Figure 4). Although arranged in a more compact and elongate pattern than in most Creagrutus species, the premaxil- lary dentition in C. gephyrus retains the three premaxillary den- tition components typical for the genus. Creagrutus cracentis and C. maxillaris share the relatively elongate premaxillary form of C. gephyrus, with the enlarged posterolateral tooth of the triad in the latter species evidently homologous with the large premaxillary tooth in a comparable position in C. cracentis and C. maxillaris (Figure 4). The tooth medial to this enlarged tooth in C. cracentis and C. maxillaris is considered to be homologous with the posteromedial tooth of the triad of teeth in most Creagrutus and Piabina species; this conclusion is based on its position and proximity to the con- tralateral tooth of the other maxilla. More problematic is a determination of the homology be- tween the remaining premaxillary teeth in C. cracentis and C. maxillaris and those in other Creagrutus species. The remain- ing teeth on the premaxilla of C. cracentis and C. maxillaris may represent the primary premaxillary tooth row in other Cre- agrutus species, albeit with more space between the anterior teeth than is typical among their congeners. If that is the case, then the anterior tooth of the triad typical for Creagrutus and Piabina species is absent in C. cracentis and C. maxillaris. Al- ternatively, the anterior tooth of the triad may have shifted dra- matically anteriorly in these two species to a position along the anterior margin of the premaxilla. Under such a scenario, the anterior tooth of the triad is now a component of what other- wise appears to be the primary tooth series. Such a homology necessitates either the loss of one tooth originally in the pri- mary series or a pronounced posterolateral shift of the second and following teeth in that series to provide space for the ante- riorly repositioned anterior tooth of the triangular cluster. This second explanation is more complex and thus less preferable. We consequently assume that the anterior tooth of the triad typ- ical for Creagrutus and its sister group, Piabina, is lacking in C. cracentis and C. maxillaris. The overall level of uncertainty with these homologies leads us, however, to score the dentition form in these two species as "?" for both Characters 2 and 3. CHARACTER 3. State 0: Anterior tooth of premaxillary tooth triad positioned, at least in part, within gap between first and second tooth in primary tooth series. State 1: Anterior tooth of premaxillary tooth triad positioned distinctly posterior of first and second teeth of primary series. An additional pronounced difference between the premaxil- lary dentition in C. cracentis and C. maxillaris and that of other Creagrutus species and Piabina argentea is the absence of the lateral tooth, the single tooth situated to the side of the primary tooth series. Although the absence of the lateral tooth is hy- pothesized to be derived for the clade consisting of C. cracentis and C. maxillaris under the overall most parsimonious hypoth- esis of relationships, it was apparently lost independently within Creagrutus in C. molinus. Creagrutus molinus lacks the attenuate form of premaxilla and the highly modified premaxil- lary triad and primary tooth row typical of C. cracentis and C. maxillaris, and to a lesser degree C. gephyrus. Instead, C. moli- nus retains the overall triangular form of the dentigerous sur- face of the premaxilla and the arrangement of the triad of teeth and the primary tooth row typical for Creagrutus species. Thus, the loss of the single tooth in C. molinus is apparently not a function of the dramatic restructuring of the premaxilla, such as occurs in C. cracentis and C. maxillaris. Creagrutus molinus, is known only from the holotype, rendering detailed anatomical examination impossible. Nonetheless, it lacks the other exter- nally apparent distinguishing features of the clade consisting of C. cracentis and C. maxillaris. In light of these differences, the secondary loss of the lateral tooth is tentatively considered to be apomorphic for C. molinus on the one hand and a shared de- rived condition for C. cracentis and C. maxillaris on the other (note: C. molinus not included in the data matrix of Table 2). CHARACTER 4. State 0: Single tooth situated lateral to pri- mary premaxillary tooth row present. State 1: Single tooth situ- ated lateral to primary premaxillary tooth row absent. MAXILLA.—Two major morphologies of the maxilla occur among Creagrutus species. The first of these, limited to C. cra- centis and C. maxillaris, is an overall relatively elongate ossifi- cation with a slender anterior process extending dorsally to- ward the lateral wing of the mesethmoid. Posterior to the premaxilla, the maxilla in these species is a transversely com- pressed, blade-like ossification with teeth along at least its an- terodorsal margin. Such a form of the maxilla also occurs in Pi- abina (Figure 5A), the sister clade to Creagrutus, and approx- imates the form of the bone widespread among characids. It is N U M B E R 613 15 B FIGURE 5.—Maxilla in (A) Piabina argentea, USNM 292220, 59.2 mm SL; and (B) Creagrutus atrisignum. USNM 341478, 50.1 mm SL; left side, lateral view, anterior to left. (Horizontal lines indicate limits of region where primordial ligament attaches to maxilla in each species. Arrows indicate approximate ventral limit of area of contact of premaxilla and maxilla.) considered to be the plesiomorphic condition for the Creagru- tus clade, albeit it is hypothesized within the final phylogeny as having been secondarily achieved in C. cracentis and C. maxil- laris. A proportionally much more robust maxilla occurs in the re- maining 62 Creagrutus species (Figure 5B). Anteriorly this re- structuring is reflected in the distinctly thicker anterior process of the maxilla that extends along the dorsal margin of the pre- maxilla. Overall maxillary robustness among these species is even more obvious in the distinctly more transversely rotund portion of the bone that extends posterior to the posteroventral corner of the premaxilla. The absence of such a robust form of maxilla in Piabina argentea, the proximate outgroup to Crea- grutus, and in examined characid outgroups is congruent with the hypothesis that the robust form of the maxilla in most Crea- grutus species is derived. CHARACTER 5. State 0: Maxilla with anterior process rela- tively slender and posterior portion transversely compressed. State 1: Maxilla with anterior process thick and posterior por- tion robust. Further distinguishing the maxilla in Creagrutus from that in Piabina argentea and other examined outgroups is the degree of inflection of the main axis of that bone in the region where the maxilla extends past the posterior limit of the premaxilla. The maxilla in Piabina argentea is nearly straight along its longest axis (Figure 5B), with only a minor inflection along its primary axis at the point where the bone extends beyond the posterior limits of the premaxilla. Creagrutus species have a much more pronounced inflection of the maxilla in that region. The degree of this flexion varies intragenerically within Crea- grutus, with a moderate angle present in three Creagrutus spe- cies (C. gephyrus, C. cracentis, and C. maxillaris; angle some- what greater in the two latter species) and a pronounced angle along the primary axis of the premaxilla common to all other species of Creagrutus (Figure 5B). The increased flexion, re- gardless of its degree, is considered to be the derived condition. CHARACTER 6. State 0: Maxilla without distinct flexion in region where it extends past posterior limit of premaxilla. State 1: Maxilla with distinct flexion in region where it extends past posterior limit of premaxilla. MAXILLARY TEETH.—Piabina argentea (Figure 5A), the sis- ter group to Creagrutus, has two to five teeth limited to the up- per portion of the anterior oral margin of the maxilla. Such a range also is common to all Creagrutus species (Figure 5B) other than C. cracentis, C. gephyrus, and C. maxillaris. These three species have distinctly higher maxillary tooth counts (C. cracentis, 8 or 9; C. gephyrus, 7 to 11; G maxillaris, 10 to 12), with the dentition extending along nearly the entire oral margin 16 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY maxilla-premaxilla ligament maxilla primordial ligament premaxilla ectopterygoid dentary quadrate FIGURE 6.—Form of primordial ligament and adjoining bones in Piabina argentea. USNM 292220,59.2 mm SL; left side, lateral view, anterior to left. of the maxilla rather than being limited to the anteroventral re- gion of the oral margin. Given the broad variation in the num- ber of maxillary teeth in the diverse groups within the Tet- ragonopterinae, it is not possible to polarize this character. CHARACTER 7. State 0: Maxilla with 2 to 5 teeth. State 1: Maxilla with 7 to 12 teeth. PRIMORDIAL LIGAMENT.—Characiforms demonstrate a broad range of modifications of the primordial ligament (sensu Winterbottom, 1974:232; the articular-maxillary ligament of Alexander, 1964:183). These differences involve both the over- all form of the ligament and details of its attachment dorsally to the maxilla and ventrally to the lower jaw and portions of the suspensorium. As would be expected, the pronounced restruc- turing of the jaws in the species of Creagrutus is paralleled by distinctive changes both in the morphology of the primordial ligament and of its attachments to the maxilla, lower jaw, and quadrate. Piabina argentea retains the primordial ligament morphol- ogy typical of many outgroup characids in which the ligament is a dorsally attenuating, relatively strap-like connective-tissue band (Figure 6). The primordial ligament in Creagrutus species (Figure 5B) is more highly developed than in outgroups, with its greater overall robustness reflected in its proportionally more rounded cross sectional dimensions, a hypothesized de- rived condition. Creagrutus also differs from Piabina and other examined outgroups in the position of the attachment of the primordial ligament on the maxilla. In Piabina the ligament attaches to the posteromedial surface of the ascending process of the maxilla approximately at the horizontal through the region where the anterior surface of the maxilla contacts the posteroventral cor- ner of the premaxilla (Figures 5A, 6). All Creagrutus species instead have the ligament attaching onto a broad area of the posterior and, to a lesser degree, the medial and lateral margins of the distal one-half (often one-third) of the maxilla (Figures 5B, 7). As a consequence, the area of attachment of the liga- ment onto the maxilla in Creagrutus is situated distinctly ven- tral of the posteroventral terminus of the premaxilla, the por- tion of the maxilla onto which the ligament attaches in Piabina and other examined outgroup characids. This ventral shift in Creagrutus species is hypothesized to be derived. Within Creagrutus the dorsal portions of the primordial liga- ment are further developed in C. amoenus and C. kunturus rela- tive to the condition in their congeners. The attachment of the ligament onto the maxilla extends further laterally than in other Creagrutus species and outgroups, and it continues ventrally nearly to the distal tip of the maxilla, a point far ventral of the limit of the attachment of the ligament in the other species of Creagrutus and examined outgroup characids. In light of its unique nature, the broadened area of attachment of the primor- dial ligament in C. amoenus and C. kunturus is considered to be a shared derived feature. CHARACTER 8. State 0: Primordial ligament relatively flat transversely and attaching to posteromedial process of ascend- NUMBF.R613 17 maxilla premaxilla dentary maxilla-premaxilla ligament primordial ligament ectopterygoid quadrate FIGURE 7.—Form of primordial ligament and adjoining bones in Creagrutus Jlavescens, USNM 340973, 58.7 mm SL; left side, lateral view, anterior to left. ing process of maxilla. State 1: Primordial ligament more ro- tund in cross section and attaching primarily to distal one-half of maxilla but not to distal portion of that bone. State 2: Pri- mordial ligament distinctly rotund in cross section and extend- ing ventrally nearly to distal tip of maxilla. Notable variability occurs in the ventral attachments of the primordial ligament among Creagrutus species. The simplest form of this attachment within Creagrutus occurs in C. mara- caiboensis, C. muelleri, C. nigrostigmatus, C. ouranonastes, and C. peruanus (see also comments below, concerning condi- tion in C. cracentis and C. maxillaris) in which the primordial ligament has the form ventrally of a single band with an attach- ment onto the lateral surface of the anguloarticular (Figure 6). Comparable forms of the primordial ligament occur in Piabina argentea and other examined outgroup characids and are con- sequently hypothesized to represent the primitive condition within Creagrutus. In the remaining Creagrutus species, the ventral portion of the primordial ligament bifurcates ventrally into a larger medial portion and a smaller posteroventral band as it extends distally from the maxilla (Figure 7). The larger medial portion of the primordial ligament in these species at- taches ventrally to the lateral surface of the anguloarticular, the area of attachment of the entire ligament in Piabina argentea, Creagrutus maracaiboensis, C. muelleri, C. nigrostigmatus, C. ouranonastes, and C. peruanus. Given the similarity in form and attachment, we consider this portion of the bifurcate pri- mordial ligament homologous with the ventral portion of the ligament in the five listed species. All Creagrutus species other than these five species also have a second, more laterally situ- ated, smaller portion of the primordial ligament extending pos- teroventrally from the main body of the ligament to an inser- tion on the lateral surface of the quadrate. The attachment of this smaller component of the primordial ligament on the quad- rate is situated slightly posterior of the articular facet on the lat- eral margin of the shelf-like process, which serves as an area of attachment for the ventral portion of the adductor mandibulae muscle. The attachment of the ligament is often onto a small lateral process extending laterally from the main shelf-like pro- cess of the quadrate. Outgroup comparisons lead us to hypothe- size that the posterolateral component of the bifurcating Crea- grutus-form of the ligament is derived from the connective- tissue layers overlying the main portion of the primordial liga- ment in examined outgroups. If such a homology is correct, the ventrally branched primordial ligament found in the vast ma- 18 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY lateral process of mesethmoid premaxilla maxilla maxilla A B FIGURE 8.—Maxilla, lateral process of mesethmoid, dorsal portion of premaxilla, and associated ligaments in (A) Piabina argentea. USNM 292220, 58.3 mm SL; and (B) Creagrutus hysginus, USNM 326035,41.3 mm SL; left side, lateral view, anterior to left. jority of Creagrutus species is of composite origin. Support for this hypothesis is provided by the form of the primordial liga- ment in Creagrutus cracentis and C. maxillaris. Although lack- ing the same form of bifurcation of the primordial ligament, such as occurs in most other members of Creagrutus, these two species have a discrete, albeit somewhat less organized, band of connective tissue that extends from the maxilla to the quad- rate and that overlies the primordial ligament. This lateral con- nective-tissue band is apparently homologous, at least in part, with the ventrolateral component of the bifurcated primordial ligament typical of most Creagrutus species. Ontogenetic stud- ies may resolve the question of the origin of the lateral portion of the ventrally bifurcating primordial ligament in most Crea- grutus species. Regardless of its origin, the more complex form of the primordial ligament in all Creagrutus species other than C. maracaiboensis, C. muelleri, C. nigrostigmatus, C. oura- nonastes, and C. peruanus is hypothesized to be derived. CHARACTER 9. State 0: Primordial ligament in form of band with single ventral attachment to lateral surface of angu- loarticular. State 1: Primordial ligament ventrally bifurcating with attachments to both the lateral surface of the anguloarticu- lar and the lateral margins of the shelf-like lateral process of the quadrate. LIGAMENTS ASSOCIATED WITH DORSAL PORTION OF MAX- ILLA.—Piabina and other outgroups to Creagrutus have a liga- mentous band extending dorsally from the anterodorsal margin of the maxilla to the ventral margin of the distal region of the lateral mesethmoid wing (the lateral ethmoid wing of Weitz- man (1962:19) and Roberts (1969:405)). The position of the maxilla relative to the premaxilla is, in turn, further stabilized by connective-tissue bands extending from the posteroventral corner of the premaxilla to the anterior surface of the maxilla at the point where the latter bone extends past the posteroventral corner of the maxilla. Although the just-described pattern of ligament is generalized for characiforms, noteworthy modifica- tions in the system of ligaments connecting the maxilla and premaxilla occur in Piabina and Creagrutus, which serve to re- duce the degree of mobility between these two ossifications. One of the most noteworthy of these alterations involves the relative size and degree of consolidation of the connective-tis- sue bands joining the posteroventral corner of the premaxilla to the anterior surface of the midsection of the maxilla. The con- nective tissues in this region are poorly to moderately devel- oped in examined tetragonopterine outgroups, permitting some mobility of maxilla relative to the premaxilla. In Piabina ar- gentea (Figures 6, 8A) and in all species of Creagrutus (Figures 7, 8B), the maxilla-premaxilia ligament is rather a highly devel- oped, discrete mass tightly joining the anterior of the maxilla to the vertical or near vertical bony notch on the posteroventral corner of the premaxilla. This expansion of the ligament in Pi- abina and Creagrutus compared with the condition in exam- ined outgroups is considered to be derived. Reductions in the mobility of the maxilla relative to the pre- maxilla also occurs in other characiforms, most notably the N U M B E R 613 19 genera Belonophago Giltay, Eugnatichthys Boulenger, Hemi- stichodus Pellegrin, Ichthyborns Giinther, Mesoborus Pelle- grin, Microstomatichthyoborus Nichols and Griscom, Paraph- ago Boulenger, and Phago Giinther of the African family Distichodontidae (Vari, 1979:273-274, fig. 4). Among these distichodontids, the greatly reduced maxilla lacks the dorsome- dial process typical for characiforms and is immovably joined, albeit not fused to the rear of the enlarged premaxilla. This re- structuring of the ossification eliminates the mobility between the premaxilla and maxilla permitted by the premaxillary-max- illary ligament in other characiforms and, furthermore, renders it impossible to determine whether that ligament is still present as a discrete body. Among New World characiforms, a signifi- cantly restructured maxilla tightly associated with the postero- dorsal margin of the premaxilla and lacking an obvious pre- maxillary-maxillary ligament occurs in Ctenolucius Gill and Boulcngerella Eigenmann, which constitute the family Ctenoluciidae (Vari, 1995:15, fig. 6). Once again it is impossi- ble to identify a discrete maxillary-premaxillary ligament in ctenoluciids. Despite these uncertainties, the cited distichodon- tids and ctenoluciids are deeply imbedded in clades whose other members have associations of the maxilla and premaxilla generalized for characiforms (Vari, 1979, and 1995, respec- tively) and have an obvious premaxillary-maxillary ligament. Thus, the adaptations in the cited ctenoluciids and distichodon- tids are not pertinent to the discussion of modifications of this system discussed above in Creagrutus. Various characid taxa (Iguanodectes Cope, Acestrorhynchus Eigenmann and Kennedy) demonstrate less pronounced alterations of the max- illa than those found in the above-cited distichodontids and ctenoluciids. These taxa, nonetheless, retain the generalized ligamentous attachments of the maxilla to the premaxilla de- scribed previously for Piabina and Creagrutus. In addition, neither of these taxa is closely aligned phylogenetically with the Tetragonopterinae (Buckup, 1998). CHARACTER 10. State 0: Ligament between posteroventral corner of premaxilla and anterior surface of maxilla moderately developed. State 1: Ligament between posteroventral corner of premaxilla and anterior surface of maxilla well developed. The degree of mobility between the maxilla and premaxilla within Creagrutus is further constrained by additional ligamen- tous attachments of the anterior portion of the maxilla to proxi- mate ossifications. Piabina argentea retains a single, well-de- veloped ligament between the anterodorsal surface of the maxilla and the distal portion of the lateral wing of the meseth- moid (Figure 8A). This condition occurs in outgroup characi- forms, and consequently it is hypothesized to be primitive for the order. In the species of Creagrutus, the anterodorsal process of the maxilla is, as previously described, both more robust and positioned closer to the posterodorsal surface of the premaxilla than in Piabina or other examined outgroup tetragonopterines. The position of the expanded anterodorsal process of the pre- maxilla relative to the dorsal surface of the maxilla in Creagru- tus species is maintained, at least in part, by two ligaments that are absent both in Piabina and in other examined outgroup tet- ragonopterines. Anteriorly Creagrutus species have a distinct ligament that extends ventrally or anteroventrally from the an- teroventral surface of the anterodorsal process of the maxilla to an attachment on the dorsal surface of the premaxilla (Figure 8B). The form of this ligament varies somewhat intrageneri- cally. At one extreme, some Creagrutus species have a distinct, approximately cylindrical, ligament with nearly equivalent ar- eas of attachment on the premaxilla ventrally and the maxilla dorsally. In other Creagrutus this ligament is triangular from a lateral view, with the extent of its attachment ventrally on the premaxilla distinctly wider than its attachment dorsally on the maxilla. In nearly all examined, cleared and stained Creagrutus spec- imens, the ligament that extends between the anterior tip of the maxilla and the dorsal surface of the premaxilla is distinct from the ligament linking the anterodorsal portion of the maxilla to the distal portion of the lateral mesethmoid wing. Some smaller examined cleared and stained Creagrutus specimens, in con- trast, have these dorsally and ventrally directed ligaments par- tially contiguous along the tip of the anterodorsal process of the maxilla. Such continuity of these ligaments is, however, absent in larger cleared and stained specimens of these species. The partial continuity between the ligaments extending dorsally and ventrally from the anterodorsal portion of the premaxilla in smaller individuals may thus be an ontogenetic stage leading to completely separated ligaments in larger conspecific speci- mens. The continuity, or lack thereof, between the ligaments and the implication of the increasing ontogenetic separation of the ligaments for hypotheses on the phylogenetic origin of the ligament extending from the anteroventral portion of the max- illa to the dorsal surface of the premaxilla require further onto- genetic study. Regardless, the occurrence of a distinct ligamen- tous band between the anterior tip of the maxilla and the dorsal surface of the premaxilla is hypothesized to be a derived fea- ture for the species of Creagrutus given its absence in exam- ined outgroup characiforms. CHARACTER 11. State 0: No ligament extending between anterodorsal tip of the maxilla and dorsal surface of premaxilla. State I: Distinct ligament extending between anterodorsal tip of maxilla and dorsal surface of premaxilla. The close association between the anterior portion of the maxilla and the dorsal portion of the premaxilla in Creagrutus species is further stabilized by a connective-tissue band extend- ing between the ventral margin of the central portion of the an- terodorsal portion of the maxilla and the proximate dorsal sur- face of the premaxilla. This ligamentous band is situated anterior of the region where the large ligament joins the poste- roventral corner of the premaxilla to the anterior surface of the maxilla (see discussion above). Within Creagrutus, this addi- tional ligament is a longitudinally aligned, band-like sheet of connective tissue extending between the maxilla and premax- illa (Figure 8B). The ligament is present in all examined Crea- grutus species but is variable in its degree of development. 20 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY anguloarticular dentary retroarticular dentary foramen FIGURE 9.—Lower jaw of Creagrutus amoenus. USNM 311339, 65.0 mm SL; left side, lateral view, anterior to left. Given the proximity of these ossifications in Creagrutus, it is often difficult to see the ligament from a lateral view without slightly separating the two ossifications. The presence of this additional maxillary-premaxillary ligament is judged to be de- rived given its absence in Piabina and other examined tetra- gonopterine outgroups. CHARACTER 12. State 0: Ligament extending between mid- ventral portion of ascending process of maxilla and dorsal sur- face of premaxilla absent. State 1: Ligament extending between midventral portion of ascending process of maxilla and dorsal surface of premaxilla present. DENTARY.—The external feature that most readily distin- guishes Piabina argentea and most Creagrutus species from the vast majority of other characids is the distinctly posterior position of the anterior margin of the lower jaw relative to the anterior limit of the upper jaw. As shown in Figure 9, the typi- cal dentary form in these genera is an anteroposteriorly com- pact structure, a morphology quite different from that in characid outgroups (see Howes, 1982, for figures of lower jaws in various Brycon species). Furthermore, the articulation be- tween the quadrate and the anguloarticular in both Piabina and Creagrutus lies along a vertical line slightly posterior of the blade-like lateral portion of the lateral ethmoid, a position of articulation typical of many characids in which the upper and lower jaws are of approximately equal lengths. This posterior location of the anterior margin of the lower jaw relative to the upper jaw in Piabina and Creagrutus is considered to be the re- sult of the foreshortened dentary (Figure 9) rather than a poste- rior shift of the relative position of the articulation of a non- shortened lower jaw with the quadrate, a repositioning that oc- curs in some other characiforms. As a consequence of the disparity in the lengths of the upper and lower jaws in the species of Creagrutus and Piabina, the cutting margins of the anterior dentary teeth on the dentary are significantly shifted posteriorly compared with the condition in numerous characid outgroups. Such a shift results in the inser- tion of the anterior dentary teeth behind the lingual margins of the two posterior teeth of the triad (see relative position of the teeth as shown in Figure 6), one of the primary components of the premaxillary dentition in both Piabina and Creagrutus. Functionally, the relative positions of these components of the dentary and premaxillary dentition create a shearing surface between the anterodorsal surface of the anterior dentary teeth and the posterior surface of two posterior teeth of the premaxil- lary triad. The shearing action between these teeth, which ap- parently serves as the main cutting area within the jaws in Cre- agrutus and Piabina, would account for the chopped up, but not finely ground or crushed, seeds and juvenile and adult in- sects that are major components of the stomach contents of these genera. Comparable positions of the upper- and lower-jaw dentition also occur in various New World characids, including some Brycon species (e.g., Brycon dentex; see Howes, 1982, fig. 13), the serrasalmine characid sister genera Colossoma Eigenmann and Kennedy and Piaractus Eigenmann (see Machado-AUison, 1983, fig. 6, for an illustration showing relative positions of up- per- and lower-jaw teeth in the closed mouth in the latter ge- nus), and some African alestids. All of these outgroup taxa re- tain a supraorbital, a feature lacking in tetragonoptcrines, including Piabina and Creagrutus. Furthermore, at least for Brycon and alestids, the phylogenetic evidence indicates that these taxa are not closely related to the Tetragonopterinae (Buckup, 1998). A great disparity in jaw lengths is absent in most characiforms, including basal lineages. Thus, the associa- tion of the upper and lower jaws in Piabina and Creagrutus is hypothesized to be derived. Functional aspects of the feeding mechanism of the cited taxa with disparate jaw lengths are unknown, with the excep- tion of that of Colossoma, which was briefly described by Irish (1983:846). She reported that seeds (experimentally almonds) NUMBER 613 21 "are anchored against the premaxillary teeth while a shearing force is applied by the mandibular [=dentary] teeth. Small pieces are sequentially broken off and sucked back into the orobranchial chamber while the body of the seed is passively held between the fleshy lips." In addition to having comparable relative positions of the teeth in the upper and lower jaws, Co- lossoma, Piabina, and Creagrutus species also possess fleshy lips, particularly the lower lip, which may serve to position food items being processed by the jaw teeth. Chopped up seeds, a common item in the stomach contents of Creagrutus and Piabina species, are a feature of the diet shared with Co- lossoma. Thus, it seems likely that species of Creagrutus and Piabina may use feeding methods similar to that reported by Irish (1983) for Colossoma, or at least do so when dealing with certain relatively hard food items, such as seeds and insect parts. Distinctly foreshortened lower jaws occur in Piabina ar- gentea and all members of Creagrutus, with the exception of C. cracentis, C. gephyrus, and C. maxillaris, which have dramati- cally restructured upper and lower jaws compared with these systems in other members of these genera. These three species, nonetheless, retain a somewhat foreshortened dentary relative to the upper jaw, with the dorsal portions of the anterior dentary teeth inserting behind the posterior teeth of the premaxilla as in their congeners. The proportional lengthening of the dentary in these species is hypothesized to be a reversal within the context of the overall intrageneric phylogeny. CHARACTER 13. State 0: Anterior terminus of dentary den- tition not distinctly posterior of anterior terminus of premaxil- lary dentition. State 1: Anterior terminus of dentary dentition distinctly posterior of anterior terminus of premaxillary denti- tion. DENTARY FORAMEN.—The dentary in all Creagrutus spe- cies, Piabina, and various other examined characids (Brycon falcatus, Bryconamericus iheringi, Chalceus macrolepidotus, Moenkhausia cotinho, Lignobrycon (formerly Moojenichthys) myersi, Triportheus angulatus) and alestids (Alestes lateral is, A. longipinnis, Viriliapabrensis) has a discrete foramen pass- ing through the bone (e.g., Creagrutus amoenus. Figure 9) that serves for the passage of the mandibular nerve through the bone. Laterally this dentary foramen opens onto the medial surface of the dentary approximately lateral to the anterior terminus of the meckelian cartilage. When present, the opening typically transverses the dentary at an oblique angle, necessitating ma- nipulation of the jaw to varying degrees to determine the course of the channel. The opening varies both in form and in position within Creagrutus. Most obvious among these condi- tions is the anteroposteriorly lengthened ovate opening on the lateral surface of the dentary in C. cracentis, C. gephyrus, and C. maxillaris. Associated with the horizontal lengthening of the opening laterally in these three species is a repositioning of the channel through the bone such that it passes directly trans- versely through the dentary rather than obliquely through that ossification as is typical of other congeners and many outgroup taxa. As a consequence of this realignment, it is possible from a lateral view in cleared and stained specimens to see through the dentary aperture to the space enclosed by the contralateral den- taries. Creagrutus species other than C. cracentis, C. gephyrus, and C. maxillaris, along with Piabina argentea and other examined outgroup characids with the channel opening on the midlateral surface of the dentary, have a rotund aperture on the outer sur- face of the dentary. Such a rotund lateral opening of the dentary foramen occurs even in outgroup characids in which the upper and lower jaws are of approximately the same length, a condi- tion comparable to that in C. cracentis, C. gephyrus, and C. maxillaris. Dentary elongation does not, per se, result in an an- teroposteriorly elongate dentary foramen, such as occurs in these three Creagrutus species. Outgroup taxa with the midlat- eral dentary apertures typically also have posteriorly angled tu- bular openings extending through the dentary contrary to the transverse orientation of the channel that occurs in C. cracen- tis, C. gephyrus, and C. maxillaris. Thus, the horizontal elonga- tion of the lateral aperture and the transverse orientation of the passage in those three species are considered to be derived con- ditions. CHARACTER 14. State 0: Dentary foramen obliquely aligned and having rotund lateral opening. State 1: Dentary fo- ramen aligned directly transversely and having horizontally elongate lateral opening. The midlateral dentary foramen also differs in its medial point of exit. The majority of Creagrutus species have the opening situated near the anterodorsal tip of the meckelian car- tilage and dorsal to the midline along the long axis of that carti- lage. In C. cracentis, C. gephyrus, and C. maxillaris, the open- ing on the medial surface of the dentary is rather immediately anterior to the tip of the meckelian cartilage and is aligned along the line through the long axis of that cartilage. A third position of the opening occurs in a small subgroup of Creagru- tus species (C melanzonus, C. phasma, C. runa) in which the opening of the passage on the medial surface of the dentary is instead located near the anteroventral tip of that cartilage but is distinctly ventral to the line extending through the longitudinal axis of the meckelian cartilage. In examined outgroup characids with the midlateral dentary foramen, the opening of the passage on the medial surface of the dentary is located anterodorsal to the tip of the cartilage and dorsal to the line through the long axis of the cartilage; thus, it matches the condition common to the majority of Creagrutus species and the outgroup Piabina argentea. This position of the aperture is consequently hypothesized to be the primitive loca- tion of the foramen for Creagrutus. The shift in the position of the medial opening to locations either anterior to, or ventral of, the anterodorsal tip of the cartilage in the two groups of Crea- grutus species (C. cracentis, C. gephyrus, C. maxillaris, on the one hand, and C. melanzonus, C. phasma, C. runa, on the 22 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY other) are considered to be derived and are coded as discrete characters. CHARACTER 15. State 0: Medial opening of dentary fora- men located anterodorsal to tip of meckelian cartilage. State 1: Medial opening of dentary foramen located immediately ante- rior to tip of meckelian cartilage. CHARACTER 16. State 0: Medial opening of dentary fora- men located anterodorsal to tip of meckelian cartilage. State 1: Medial opening of dentary foramen located distinctly an- teroventral to tip of meckelian cartilage. LATEROSENSORY CANAL SEGMENT IN DENTARY.—The den- tary in characiforms typically has a bony canal along its ventro- lateral surface that encloses a portion of the laterosensory canal system. In Piabina argentea and in all species of Creagrutus, with the exception of C. maracaiboensis, the canal extends from the region of contact of the anguloarticular anteriorly to a point approximately three-fourths of the distance toward the dentary symphysis, which is the generalized characiform con- dition (anterior opening of mandibular laterosensory canal seg- ment shown as unlabeled foramen located ventral to large sec- ond tooth in Figure 9). Creagrutus maracaiboensis, in contrast, lacks the ossified posterior portion of the laterosensory canal segment in the dentary. As a consequence, that species retains only a short, isolated, laterosensory canal segment that extends along approximately the middle one-third of the lateral surface of the dentary. This is a reductive autapomorphy for C. mara- caiboensis. DENTARY TEETH.—The number of teeth on each dentary falls into two distinct groups within Creagrutus. Creagrutus cracentis, C. gephyrus, and C. maxillaris have a range of 10 to 12 teeth on each dentary. The remaining Creagrutus species have four to seven dentary teeth (e.g., Creagrutus amoenus. Figure 9), a range that also occurs in Piabina and many other outgroup characids and is considered to be plesiomorphic. The increased tooth number in C. cracentis, C. gephyrus, and C. maxillaris is consequently considered to be derived. CHARACTER 17. State 0: Dentary teeth 4 to 7. State 1: Den- tary teeth 10 to 12. An additional feature common to Creagrutus cracentis, C. gephyrus, and C. maxillaris is their possession of four or five cusps on the anterior dentary teeth in contrast to the three cusps present in the remaining species of Creagrutus (e.g., Creagru- tus amoenus, Figure 9). These one or two additional, very small cusps flank the posterior (when four cusps are present) or anterior and posterior (when five cusps are present) lateral cusps present in other Creagrutus species. Recently emerged teeth, as indicated by their sharp cutting edges and in some in- stances only by their partially ossified basal portions, have these additional cusps quite distinct. Such smaller cusps on these teeth are not apparent on older teeth, as indicated by their rounded cutting edges; their absence is most likely a conse- quence of mechanical erosion. Although tricuspidate teeth are quite common among tetragonopterines, including Piabina ar- gentea, the sister group to Creagrutus, various tetragonopterin taxa also have increased numbers of cusps on the dentary teeth. As a consequence of this variation in outgroups, we treat the character as unordered. CHARACTER 18. State 0: Anterior dentary teeth with 3 cusps. State 1: Anterior dentary teeth with 5 cusps. ANGULOARTICULAR.—Associated with the foreshortening of the lower jaw in Piabina and Creagrutus is a reduction in the antero-posterior extent of the anguloarticular. From a lateral view, the anguloarticular appears vertically elongate, rather than having the more horizontal expanse typical of outgroup characids (Figure 9). Examined at the level of the horizontal through the articular socket, which contacts the condylar sur- face of the quadrate, this antero-posterior shortening is mani- fested by the near contact of the posterior portion of the dentary and the posterior surface of the laterally expanded articular socket. The three species of Creagrutus (C. cracentis, C. ge- phyrus, C. maxillaris) with secondarily elongated jaws, none- theless, retain the same overall form of the anguloarticular, al- beit with a proportionally slightly increased space between the posterior margin of the dentary and the articular socket of the anguloarticular. The reduced, vertically elongate form of the anguloarticular is coded as derived and is a synapomorphy for Creagrutus. CHARACTER 19. State 0: Anguloarticular not as in 1. State 1: Anguloarticular horizontally foreshortened. The posterodorsal portion of the anguloarticular in the ma- jority of Creagrutus species has a posterior margin that ranges from being nearly vertical to being somewhat convex and ex- tending posterior of the articular facet on that ossification, a morphology that also is present in Piabina argentea. the first outgroup to Creagrutus (Figure 9). Two Creagrutus species, C. cracentis and C. maxillaris, instead have a distinctly anterodor- sally angled dorsal margin of the anguloarticular, a modifica- tion considered to be derived in light of its absence in Piabina and other examined characid outgroups. CHARACTER 20. State 0: Margin of posterodorsal portion of anguloarticular vertical to somewhat convex. State 1: Margin of posterodorsal portion of anguloarticular distinctly anterodor- sally angled. The characiform anguloarticular typically has a short lat- erosensory canal segment positioned ventrally and immedi- ately above its articulation with the retroarticular. This canal segment is uniquely absent in Creagrutus maracaiboensis within Creagrutus. Although Creagrutus maracaiboensis achieves some of the smallest maximum known body sizes within the genus, its diminutive size is not, per se, the explana- tion for its lack of a sensory canal segment in the anguloarticu- lar. A specimen of C. nigrostigmatus, another diminutive spe- cies, of comparable size to the examined C. maracaiboensis specimens has a fully developed laterosensory canal in the an- guloarticular, and the canal segment is present in even smaller individuals of C. magdalenae, a species that achieves distinctly larger body sizes as an adult than does C. maracaiboensis. NUMBER 613 23 mesopterygoid mesopterygoid ectopterygoid metapterygoid quadrate metapterygoid ectopterygoid quadrate A B FIGURE 10.—Central portions of suspensorium in (A) Piabina argentea, USNM 292220, 59.2 mm SL; and (B) Creagrutus amoenus, USNM 311339, 65.0 mm SL; left side, lateral view, anterior to left. (Dashes indicate limits of connective tissue.) SUSPENSORIUM RELATIONSHIP OF ECTOPTERYGOID AND QUADRATE.—The ectopterygoid either contacts or overlaps the anterodorsal por- tion of the quadrate to varying degrees in a most characiform groups. Characiform taxa demonstrating such contact between these two bones include components of the family Characidae (e.g., Cynopotamus Valenciennes, Galeocharax Fowler, and Acestrocephalus Eigenmann, see Menezes, 1976, figs. 11-13; Brycon, see Weitzman, 1962, fig. 10), Acestrorhynchidae (Ac- estrorhynchus, see Roberts, 1969, fig. 32), Alestidae (Alestes Miiller and Troschel, Chalceus Cuvier, and Triportheus Cope), Anostomidae (Schizodon Agassiz, see Roberts, 1973, fig. 12), Curimatidae (Potamorhina Cope, see Vari, 1983, fig. 27), Erythrinidae (Hoplias Gill, see Roberts, 1969, fig. 29), Hemi- odontidae (Hemiodus Miiller, see Roberts, 1974, fig. 8), Heps- etidae (Hepsetus Swainson, see Roberts, 1969, fig. 26), and Lebiasinidae (Poecilobrycon Eigenmann, see Weitzman, 1964, fig. 7), and basal family Distichodontidae {Xenocharax Gunther, see Fink and Fink, 1981, fig. 11). Species of Creagrutus, with the exception of C. mucipu along with Piabina argentea, differ from this generalized characiform condition in their lack a direct bony contact of the ectopterygoid and the quadrate, although with different degrees of separation of the bones. In Piabina argentea the posteroven- tral margin of the ectopterygoid approaches, but does not con- tact, the anterodorsal portion of the quadrate (Figure 10A). The species of Creagrutus other than C mucipu, in contrast, have a distinct gap between the proximate portions of the ectoptery- goid and quadrate (Figures 10B, 11). In the absence of direct ectopterygoid-quadrate contact, both Piabina and Creagrutus have a relatively thick sheet of connective tissue flexibly ex- tending from the posteroventral margin of the ectopterygoid to the anterodorsal section of the quadrate. Creagrutus mucipu, the only member of the genus with contact between these bones, has a slight overlap of the posteroventral portion of the ectopterygoid over the quadrate. The overlap between these bones in C. mucipu is less pronounced than in most characi- forms and is considered to be a secondary reacquisition of this feature within the context of the overall most parsimonious hy- pothesis of relationships. Such ectopterygoid-quadrate separation in Piabina and nearly all Creagrutus species is judged to be derived, given the bony contact of these elements in most characiform outgroups, including the basal family Dis- tichodontidae. A lack of direct contact between the ectopterygoid and the quadrate occurs in a few other characiforms. Within the Hemi- odontidae the ectopterygoid and quadrate are separate in Ano- dus Agassiz (Roberts, 1974, fig. 45; Langeani, 1998, fig. 7). These two ossifications, however, overlap to varying degrees in Micromischodus Roberts, the sister group to Anodus, and in Bivibranchia Eigenmann, Hemiodus, and Argonectes Bohlke and Myers, the remaining hemiodontid genera that form the sister group to the clade formed by Micromischodus and Ano- dus (Langeani, 1998, fig. 22). Thus, the lack of ectopterygoid- quadrate contact in Anodus is most parsimoniously hypothe- sized as homoplastic to this condition in Creagrutus and Pia- 24 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY hyomandibula, metapterygoid mesopterygoid ectopterygoid quadrate quadrate ridge preopercle FIGURE 11.—Central portions of suspensorium in Creagrutus barrigai. USNM 340976, 45.6 mm SL; left side, lateral view, anterior to left. bina. The ectopterygoid and quadrate also are separated in Par- odon Valenciennes of the Parodontidae (see Roberts, 1974, fig. 70), whereas these bones are in contact in Saccodon Kner and Apareidon Eigenmann, which are the remaining genera of the Parodontidae. Although intrafamilial phylogenetic relation- ships of parodontids have yet to be critically analyzed, the fam- ily is undoubtedly monophyletic (Starnes and Schindler, 1993) and is furthermore phylogeneticaly distant from the Tet- ragonopterinae (Buckup, 1998). The separation of the ectop- terygoid and quadrate in Parodon is consequently judged to be homoplastic relative to the lack of contact of those bones in Pi- abina argentea and the species of Creagrutus. CHARACTER 21. State 0: Ectopterygoid and quadrate in contact, typically with distinct degree of overlap. State 1: Ec- topterygoid and quadrate not in contact. RELATIONSHIP OF MESOPTERYGOID AND METAPTERY- GOID.—Associated with the loss of direct contact of the ectop- terygoid and quadrate in Creagrutus and Piabina is a change of the relationship of the mesopterygoid and metapterygoid. Out- group characiforms cited in the previous section all demon- strate a broad overlap of the posteroventral portion of the me- sopterygoid onto the anterodorsal portion of the metapterygoid. Piabina argentea has a reduction of the posteroventral portion of the mesopterygoid compared to the condition in many out- group characids but, nonetheless, retains an overlap of that os- sification and the metapterygoid (Figure 10A), albeit to a less pronounced degree than in outgroup characid taxa. Creagrutus species, with the exception of C. gephyrus, have a pronounced reduction of the posteroventral portion of the me- sopterygoid resulting in a distinct separation of the posterior margin portion of the mesopterygoid from the border of the an- terodorsal region of the metapterygoid (Figures 1 OB, 11). The proximate portions of the metapterygoid and mesopterygoid, in the absence of osseous contact, are joined by a connective-tis- sue sheet. This sheet is not as well developed as that extending between the separated ectopterygoid and quadrate in Piabina and Creagrutus. Such a separation of the mesopterygoid and metapterygoid in all Creagrutus species other than C. gephyrus is hypothesized to be derived given the contact and/or overlap of those two ossifications in examined characiform outgroups. As noted, the one exception to the general separation of the mesopterygoid and metapterygoid in Creagrutus species oc- NUMBER 613 25 curs in C. gephyrus in which the degree of overlap of the two ossifications is comparable to that in Piabina. Within the con- text of the final most parsimonious hypothesis of phylogenetic relationships within the genus, the overlap of these elements in C. gephyrus is hypothesized to be a reversal of the lack of con- tact of these ossifications typical for Creagrutus species. The ectopterygoid, mesopterygoid, and palatine in Creagru- tus species are tightly conjoined by connective tissue and by the elongate band of cartilage that extends along their proxi- mate margins. The resultant tightly joined unit in Creagrutus is somewhat mobile relative to the more posterior components of the suspensorium, other than in the case of C. gephyrus, which has an apparently inflexible overlap of the mesopterygoid and metapterygoid. The functional significance of the resultant mo- bility is uncertain, but perhaps it is associated with the shearing action of the anterior dentary teeth and the posterior premaxil- lary teeth discussed above. Various degrees of mobility of an anterior element of the sus- pensorium relative to the more posterior portion of the system also occurs among characiforms in members of the Hemiodon- tidae and Parodontidae and in the Anostomidae in Gnathodolus Myers (see discussion in Vari, 1983:30). In none of these out- group characiform taxa, however, does the intra-suspensorium mobility involve movement between a unit formed by con- joined ectopterygoid, mesopterygoid, and palatine relative to the posterior components of the suspensorium. Furthermore, the phylogenetic relationships of all of these taxa are distant from the Tetragonopterinae, including Creagrutus (Buckup, 1998). CHARACTER 22. State 0: Mesopterygoid and metapterygoid overlapping along their area of contact. State 1: Mesopterygoid and metapterygoid separate. METAPTERYGOID.—Nearly all Creagrutus species have a distinct transverse foramen located in the posterior portion of the metapterygoid, and such an aperture also is present in Pia- bina argentea, the sister group to Creagrutus. This aperture (Figure 11) serves as a channel for a large blood vessel; the posterior margin of the opening is formed by a distinct bony bridge. In two Trans-Andean Creagrutus species (C. maracai- boensis and C. nigrostigmatus) and one Amazonian species (C. zephyrus), the passage for the blood vessel rather than being bordered posteriorly by a bony bridge instead opens along the rear margin of the metapterygoid. This is a unique and evi- dently derived condition within Creagrutus. It is noteworthy that C. maracaiboensis and C. nigrostigma- tus achieve the smallest known maximum adult body sizes in Creagrutus, and the cleared and stained specimens of C. zephyrus also are relatively small. Comparable incomplete clo- sures of the metapterygoid foramen occur in juveniles of other Creagrutus species, the adults of which have a fully enclosed opening in the metapterygoid. Thus, the incomplete enclosure of the foramen in C. maracaiboensis and C. nigrostigmatus is potentially a consequence of a paedomorphic process reflecting the diminutive adult body sizes of these species, with the in- complete closure of the foramen in the cleared and stained specimens of C. zephyrus possibly a function of their size. CHARACTER 23. State 0: Metapterygoid foramen enclosed within metapterygoid. State 1: Metapterygoid foramen open posteriorly. Piabina argentea and Creagrutus species demonstrate varia- tion in the form of the anteroventral process of the metaptery- goid, which extends anteriorly to meet a comparable process from the quadrate situated along the dorsal margin of the sym- plectic. Some species in these genera have a distinct separation between the tips of these processes, with the intervening gap filled by an elongate cartilage. Other species have a nearly di- rect contact of the processes, with a relatively limited amount of intervening cartilage. The continuity in the degree of devel- opment of this process within this assemblage renders the as- signment of species to particular character states problematic, making it impossible to utilize this variation for phylogenetic purposes. Two species with contact of well-developed metap- terygoid and quadrate processes, C. lassoi and C. gyrospilus, have, however, a distinct, vertically expanded region of contact between the adjoining portions of the two processes. The de- gree of development of the area of contact is such that the joint is slightly expanded dorsally into the ventral portion of the metapterygoid-quadrate fenestra, a unique and derived condi- tion. CHARACTER 24. State 0: Contact of metapterygoid and quadrate in region dorsal of symplectic either cartilaginous or bony but not vertically expanded. State 1: Contact of metap- terygoid and quadrate in region dorsal of symplectic via verti- cally expanded bony contact. Nearly all Creagrutus species have the anteroventral process of the metapterygoid extending anteriorly to meet a compara- ble process from the quadrate situated along the dorsal margin of the symplectic. This contact is located approximately at the level of the horizontal through the ventral tip of the hyoman- dibula. The single exception is C. lepidus in which the an- teroventral process of the metapterygoid (and the matching process on the quadrate, see "Quadrate," below) is positioned distinctly dorsal of the upper margin of the symplectic and of the horizontal through the ventral tip of the hyomandibula. As a consequence of its dorsal shift, the metapterygoid process and the matching process on the quadrate in C. lepidus dorsally de- limit an opening that is, in turn, bordered ventrally by the sym- plectic. This additional fenestra in the suspensorium is situated below the large metapterygoid-quadrate fenestra present in most groups of characiforms. In light of its unique nature among examined characiforms, the aperture is considered to be an autapomorphy for C. lepidus. QUADRATE.—The typical characiform quadrate has a slender posterodorsal process that extends posteriorly above the sym- plectic and that contacts the anteroventral process of the metap- terygoid via an intervening cartilage body. In the typical characiform condition, this posterodorsal quadrate process is smoothly continuous with the slightly more laterally located 26 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY proximate portion of the main body of the quadrate. This gen- eralized characid morphology of this portion of the quadrate is present in Piabina argentea. Creagrutus species have instead a variably developed vertical ridge or process extending dorsally from the main body of the quadrate in, and posterior to, the re- gion where the posterodorsal process of the quadrate contacts the anteroventral process of the metapterygoid. This dorsally developed process is situated distinctly lateral of the typical posterodorsal process of the quadrate. When well developed, it covers (from a lateral view) the anterodorsal portion of the symplectic and the anteroventral portion of the posterior region of the metapterygoid (Figure 11). In light of its unique nature among examined characiforms, this quadrate process is consid- ered to be a derived condition. CHARACTER 25. State 0: Not as in state 1. State 1: Quadrate with variably developed vertical ridge or process extending dorsally from main body of the quadrate in, and posterior to, region where posterodorsal process of quadrate contacts an- teroventral process of metapterygoid. The only exception to the general Creagrutus form of this process of the quadrate occurs in C. lepidus in which the ridge is poorly developed. That reduction in the ridge on the quad- rate, in combination with the dorsal shift in the contact of the anteroventral portion of the metapterygoid (see above under "Metapterygoid") and the posterodorsal process of the quad- rate, results in those processes being visible in lateral view. The dorsal shift of the posterodorsal process of the quadrate in C. lepidus also contributes to the fenestra delimited by that pro- cess, the matching process of the metapterygoid, and the sym- plectic. This modification, unique to C. lepidus among the spe- cies of Creagrutus. was not encountered in examined characid outgroups, so it is considered to be derived. HYOMANDIBULA.—The hyomandibula is a complex bone with several modifications of interest in Creagrutus. When ex- amined in lateral or medial view the most obvious of these modifications is the expansion anteriorly of the anteromedial portion of the ossification (Figure 11). As a consequence, this portion of the hyomandibula extends over the posterodorsal re- gion of the metapterygoid, with the degree of extension vari- able within Creagrutus. This form of hyomandibula differs from the typical characid condition in which the anterior mar- gin of the hyomandibula is straight or even slightly concave (e.g., Brycon meeki; see Weitzman, 1962, fig. 10), and its pres- ence in Creagrutus species is consequently considered to be a derived condition. CHARACTER 26. State 0: Anterior margin of hyomandibula straight or slightly concave. State 1: Anterior margin of hyo- mandibula anteriorly expanded and extending over posterodor- sal region of metapterygoid. The dorsal margin of the hyomandibula also demonstrates a modification involving the association of the ossification with the neurocranium. When examined from a dorsal view, the por- tion of the hyomandibula that articulates with the cranial hyo- mandibular fossa in characids is symmetrical about an antero- posterior line and is typically rectangular overall or somewhat pinched midway along its length. The vast majority of species of Creagrutus along with Piabina argentea have, in contrast, a highly asymmetrical profile of the dorsal articular surface of the hyomandibula when viewed from the dorsal view. In these species the anterior portion of the articular surface of the hyo- mandibula is distinctly expanded laterally compared with the condition in tetragonopterine outgroups. Underlying this ex- panded portion of the articular surface is a progressively ven- tral ly attenuating lateral buttress on the hyomandibula, another distinctive feature for this assemblage. Both the lateral expan- sion of the articular surface and the associated lateral expan- sion of the adjoining portion of the hyomandibula in Piabina argentea and most Creagrutus species are thus considered to be derived. The restructurings of the dorsal portions of the hyomandib- ula described above are, however, absent in three Creagrutus species (C. cracentis, C. gephyrus, C. maxillaris). These spe- cies have nearly symmetrical articular surfaces on the dorsal margin of the hyomandibula, the generalized tetragonopterine condition. Within the context of the overall phylogenetic analy- sis this is judged to be a single secondary reversal to the gener- alized characid condition. CHARACTER 27. State 0: Dorsal articular surface of hyo- mandibula nearly symmetrical; hyomandibula without dorso- lateral buttress. State 1: Dorsal articular surface of hyomandib- ula asymmetrical; hyomanibula with dorsolateral buttress. ANTORBITAL AND INFRAORBITALS ANTORB1TAL.—The typical shape of the antorbital in Crea- grutus is an elongate, posterodorsally inclined ossification with a slight medial flexure and moderate anteroventral expansion. This condition also is present in Piabina argentea and other ex- amined outgroups. In two Creagrutus species (C. lepidus, C. melasma) the anteroventral portion of the ossification is ex- panded relative to the condition in congeners. This restructur- ing results in an anteroposteriorly wider antorbital that in a lat- eral view is characterized by a distinct posteroventral angle along its longest axis. Given the absence of such an expansion in its congeners or in Piabina, the sister group to Creagrutus, the antorbital form in C. lepidus and C. melasma is hypothe- sized to be a derived condition. CHARACTER 28. State 0: Antorbital elongate, with slight medial flexure and moderate anteroventral expansion. State 1: Antorbital distinctly wider anteriorly and with distinct angle. FIRST INFRAORBITAL.—The first infraorbital (IO i) demon- strates a notable degree of variation in overall form across Cre- agrutus. Continuity across this variation, however, mostly pre- cludes the unequivocal recognition of discrete character states across this morphological variability. The single exception in- volves the degree of development of the anterior portion of the laterosensory canal segment in the first infraorbital. In Piabina argentea the anterior portion of the laterosensory canal seg- NUMBER 613 27 ment in the first infraorbital terminates distinctly posterior of the anterior margin of the plate-like main body of the ossifica- tion. Creagrutus species, in contrast, have the laterosensory ca- nal segment extending forward as far as, or beyond, the ante- rior limit of the first infraorbital. This anterior extension of the laterosensory canal segment in the first infraorbital in Creagru- tus species demonstrates an intrageneric range in form from a discrete tube integral to the plate-like anterior portion of the bone to a distinct ossified tube extending forward of the main, plate-like portion of the bone. Outgroup tetragonopterines have variable degrees of development of the laterosensory canal in the first infraorbital making it impossible to polarize the char- acter. CHARACTER 29. State 0: Anterior portion of the laterosen- sory canal segment in first infraorbital terminating distinctly posterior of anterior margin of bone. State 1: Anterior portion of laterosensory canal segment in first infraorbital reaching or extending beyond anterior margin of main body of ossification. JOINT BETWEEN FIRST AND SECOND INFRAORBITALS.—Two distinct conditions of the joint between the first and second in- fraorbitals (101 and IO2, respectively) occur within Creagru- tus. In two species (C. lepidus, C. melasma) the adjoining mar- gins of these ossifications abut without overlap. Other Creagrutus species have the posterior portion of the first in- fraorbital overlapping the anterior portion of the second in- fraorbital, with variation in the degree of overlap between spe- cies. No overlap between the first and second infraorbitals occurs in Piabina, the sister group to Creagrutus. Given the variability in this feature among other tetragonopterines, we are unable to polarize this feature. CHARACTER 30. State 0: First and second infraorbitals abutting without overlap. State 1: Posterior portion of first in- fraorbital overlapping anterior portion of second infraorbital. The form of the area of contact between the first and second infraorbitals in C. maracaiboensis, a diminutive species en- demic to the Lago Maracaibo basin, cannot be determined and consequently is coded as "?." In the region anteroventral to the orbit, C. maracaiboensis has a single ossification in the space filled by the first and second infraorbitals in the remaining Cre- agrutus species. We are unable to determine whether this ossi- fication represents a fusion of the first and second infraorbitals, or the loss of one of these elements with the subsequent expan- sion of the remaining infraorbital into the space originally oc- cupied by the lost element. Regardless of its identity, this form of infraorbital, unique within Creagrutus, is an autapomorphy for C. maracaiboensis. FOURTH INFRAORBITAL (IO4).—The fourth infraorbital var- ies both in form and relative size in the assemblage formed by Piabina and Creagrutus; however, continuity across this varia- tion renders it mostly impossible to delimit discrete character states. The one exception to that generality involves the form of the ossification in Piabina argentea, the single species of the genus. In all Creagrutus species the fourth infraorbital is ap- proximately quadrilateral (Figure 12A), the condition present in most characiformes. In Piabina argentea the fourth infraorbital is rather triangular with an acute posterior angle (Figure 12B). Smaller specimens off! argentea have the posteriorly tapering portion of the fourth infraorbital contributing to the posterior margin of the infraorbital ring, at least to a limited degree. Dur- ing ontogeny, P. argentea demonstrates a differential expansion of the posterior portions of the third through fifth infraorbitals, with the fourth infraorbital expanding posteriorly to a lesser de- gree than the third and fifth infraorbitals. This differential de- velopment and the resultant contact of the third and fifth in- fraorbitals along the posterior margin of the infraorbital ring excludes the fourth infraorbital from the posterior infraorbital margin in larger individuals of P. argentea. Exclusion of the fourth infraorbital from the posterior margin of the infraorbital series in P. argentea contrasts with the situation in all Creagru- tus species in which the fourth infraorbital contributes to the posterior margin of the infraorbital ring, a condition that also is generalized for most tetragonopterines (e.g., Hemibrycon Giinther; see Gery, 1962, fig. 5) and indeed characiforms. Re- tention of contact consequently is judged to be plesiomorphic, whereas the morphology of the fourth infraorbital in Piabina is considered to be derived, although not unique among characi- forms. A fourth infraorbital excluded from the posterior margin of the orbital ring also occurs in two clades of the family Ctenoluciidae (Van, 1995:12, fig. 1). The first clade consists of Ctenolucius beani (Fowler) and C. hujeta (Valenciennes), and the second consists of Boulengerella cuvieri (Agassiz), B. lu- cius (Cuvier), and B. xyrekes Vari. One notable difference be- tween the Piabina condition of the fourth infraorbital and that in ctenoluciids is the proportionally significantly smaller ossifi- cation among ctenoluciids. Such proportional differences do not, a priori, render the reduced fourth infraorbitals in ctenoluciids homoplastic relative to that in Piabina. Ctenoluci- ids are, however, deeply nested within a series of sequential clades that include neither Creagrutus nor Piabina (Vari, 1995, fig. 15) and that retain a quadrangular fourth infraorbital ex- tending to the posterior margin of the infraorbital series. Con- sequently, the occurrence of a reduced fourth infraorbital ex- cluded from the posterior rim of the infraorbital series in ctenoluciids is most parsimoniously judged to be homoplastic to the presence of the somewhat similar condition in Piabina argentea. Elsewhere among characiforms, a reduced fourth infraorbital also occurs in the characid Roeboides Giinther. Lucena (1998:40, fig. 4) reported a posteriorly attenuating triangular fourth infraorbital falling short of the posterior infraorbital margin in larger individuals of R. dayi Steindachner, R. occi- dentalis Meek and Hildebrand, R. bouchellei Fowler, R. diento- nito Schultz, and R. ilsea Bussing. The remaining Roeboides species lack the ossification, as is shown by their possession of only five infraorbitals. In his phylogenetic analysis, Lucena (1998:28) advanced a series of characters that support the hy- pothesis of the monophyly of Roeboides and demonstrated that 28 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY fifth infraorbital third infraorbital B FIGURE 12.—Third through fifth infraorbitals of (A) Creagrutus menezesi, USNM, 292229, 61.8 mm SL; and (B) Piabina argentea, USNM 292220,59.2 mm SL; left side, lateral view, anterior to left. under the most parsimonious hypothesis of relationships the re- duced fourth infraorbital in some Roeboides species is a reacquisition of the ossification (Lucena, 1998:39—40). In an earlier study Lucena (1993) advanced information indicating that the relationships of Roeboides lie with taxa traditionally placed in the subfamily Characinae, an assemblage defined by features absent in Piabina and the Piabina-Creagrutus clade. Thus, the posteriorly attenuating fourth infraorbital in R. occi- dentalis is consequently hypothesized to be homoplastic to that in Piabina. CHARACTER 31. State 0: Fourth infraorbital approximately quadrangular and contributing to posterior margin of infraor- bital series at all sizes. State 1: Fourth infraorbital approxi- mately triangular and excluded from posterior margin of in- fraorbital series in medium- to large-sized individuals. FIFTH INFRAORBITAL.—The fifth infraorbital within Crea- grutus generally has a distinct posterodorsal process (Figure 12) that is situated posterior to the relatively small sixth in- fraorbital (=dermosphenotic); this condition also is present in the first outgroup, Piabina argentea. Creagrutus lepidus, uniquely within the genus, lacks this posterodorsal process of the fifth infraorbital and as a consequence has the sixth infraor- bital situated completely dorsal of the fifth infraorbital. Al- though adult C. lepidus attain relatively small body sizes com- pared to many congeners, their lack of the posterodorsal process of the fifth infraorbital cannot be ascribed to that factor. This posterolateral process of the fifth infraorbital is present in other Creagrutus species at body sizes comparable to those of adults of C. lepidus in which the process is absent. The absence of the process on the fifth infraorbital is hypothesized to be au- tapomorphic for C. lepidus in light of the broad distribution of such a process within Creagrutus and its immediate outgroup, Piabina. BRANCHIAL ARCHES FOURTH BASIBRANCHIAL TOOTH-PLATE.—The fourth basi- branchial (BB4) is a variably developed median cartilage. Be- ginning immediately posterior of the partially to completely os- sified third basibranchial, the cartilaginous fourth basibranchial extends posteriorly between the medial portions of the con- tralateral fourth ceratobranchials to terminate at, or beyond, the anterior portions of the fifth ceratobranchials. The dorsal sur- face of the fourth basibranchial in examined outgroups, includ- NUMBER 613 29 A B FIGURE 13.—Fifth ceratobranchial of (A) Piabina argentea, USNM 292220, 59.2 mm SL; and (B) Creagrutus magoi, USNM 292220, 59.2 mm SL; right side, dorsal view, anterior at top, larger stippling represents cartilage. ing Piabina argentea, bears a bony plate. That ossification also is present in all but fourteen Creagrutus species (C. atratus, C. barrigai, C. bolivari, C. gephyrus, C. gracilis, C. machadoi, C. magdalenae, C. mucipu, C. paralacus, C. pila, C. seductus, C. taphorni, C. vexillapinnus, C. zephyrus). Given the common occurrence of the ossification in outgroups, including Piabina, its absence in some Creagrutus species is considered to be de- rived. CHARACTER 32. State 0: Dorsal surface of fourth basibran- chial bearing body plate. State 1: Dorsal surface of fourth basi- branchial without body plate. FIFTH CERATOBRANCHIAL.—The fifth ceratobranchial (C5) in the Characidae has two primary components when observed from dorsal view. The first is the anteromedially aligned main shaft whose orientation matches the longitudinal alignment of the more anterior ceratobranchials. Medial to this main shaft is a tooth-bearing triangular portion with a patch of teeth cover- ing its dorsal surface (Figure 13). The junction of the posterior margin of the tooth-bearing portion of the fifth ceratobranchial with the main shaft of the bone ranges between a right angle and a distinctly obtuse angle. Along its lateral margin, the fifth ceratobranchial tooth patch extends approximately in parallel with the axis of the main shaft of the bone. Medially the tooth patch extends distinctly forward of the transverse level through the point where the tooth-bearing portion of the bone contacts the main shaft of the fifth ceratobranchial. Such a morphology of the fifth ceratobranchial and its tooth patch occurs in diverse characids (e.g., Brycon falcatus Miiller and Troschel (see also Weitzman, 1962, fig. 11, for B. meeki Eigenmann and Hilde- brand), Bryconamericus iheringi (Boulenger), Triportheus an- gulatus (Spix), and Tetragonopterus sp.) and alestids (e.g., Al- estes lateralis Boulenger, Virilia pabrensis (Roman)). This generalized characid and alestid arrangement of the fifth ceratobranchial also occurs in Piabina argentea (Figure 13A), but within Creagrutus it is limited to C. maracaiboensis and C. nigrostigmatus. The remaining Creagrutus species have the tooth-bearing portion of the fifth ceratobranchial relatively reduced and extending not as far anteriorly along the medial margin of the bone (Figure 13B). More notably, the tooth-bear- ing portion of the fifth ceratobranchial is reduced along its lat- eral margin, resulting in a distinct concavity along the posterior margin of the fifth ceratobranchial in the region where the tooth-bearing portion of the fifth ceratobranchial meets the main shaft of the bone. This restructuring of the tooth-bearing portion of the fifth ceratobranchial and the associated reduction in the extent of the toothed portion of that ossification in most Creagrutus species is considered to be derived, given the con- dition in examined outgroups. Among examined outgroup taxa only the iguanodectine characid Piabucus melanostomus has a fifth ceratobranchial form somewhat comparable to that in the majority of Creagru- tus species. Although Piabucus melanostomus has a deeply in- dented posterior margin of the tooth-bearing portion of the bone, the dentition on the fifth ceratobranchial extends along much of the medial margin of that ossification rather than be- ing limited to the posterior portion of the bone. Furthermore, Piabucus and its sister genus, Iguanodectes (Van, 1977), which together constitute the subfamily Iguanodectinae, lack the other 30 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY derived features common to Creagrutus and Piabina and also lack the synapomorphies for the species of Creagrutus. Thus, the similar form of fifth ceratobranchial in Piabucus melanos- tomus and the majority of Creagrutus species are considered homoplastic. CHARACTER 33. State 0: Dentigerous portion of fifth certo- branchial well developed and elongate, meeting main shaft of ossification approximately at a right angle. State 1: Dentiger- ous portion of fifth certobranchial smaller and rotund, meeting main shaft of ossification approximately at a distinctly acute angle. THIRD INFRAPHARYNGOBRANCHIAL.—The presence of den- tition on the posteroventral portion of the third infrapharyngo- branchial (PB3) is common to diverse characids (e.g., Brycon falcatus; see Vari, 1989, fig. 17), although with variation in the form of the tooth patch and number of teeth. Dentition on the third infrapharyngobranchial is absent in Piabina argentea but is present in a subset of Creagrutus species, including four of the eight members of the genus living to the west of the An- dean Cordilleras (C. a/finis, C. brevipinnis, C. caucanus, C. hildebrandi) and a much smaller percentage of the Cis-Andean species (C. anary, C. atrisignum, C. beni, C. changae, C. hol- mi, C. kunturus, C. manu, C. meridional is, C. ortegai, C. pear- soni, C. pi la, C. runa, C. saxatilis, C. zephyrus). In the absence of information on proximate outgroups to Creagrutus beyond Piabina, it is not possible to polarize this character. CHARACTER 34. State 0: Dentition on third infrapharyngo- branchial absent. State 1: Dentition on third infrapharyngo- branchial present. CRANIUM Components of the cranium pertinent to the phylogenetic re- construction are discussed starting with the dorsal elements in an anterior to posterior direction, followed by more ventral os- sifications in the same sequence. MESETHMOID.—Anteriorly the mesethmoid in characids typ- ically terminates in a conic process that forms the anteriormost portion of the cranium. The anterior portion of the mesethmoid in characids usually extends directly, or nearly directly, for- ward, typically in the form of an anteriorly tapering, sometimes attenuate, triangle that serves as a broad area of attachment for the median surfaces of the con tralateral premaxillae. In Piabina and Creagrutus this anterior portion of the mesethmoid is ex- panded ventrally compared with the condition in other exam- ined characids. As a consequence, this portion of the meseth- moid in these genera forms a variably anteroventrally expanded process that extends between the premaxillae nearly as far as the ventral surface of the median suture between those bones (Figure 14). This expansion of the mesethmoid takes two forms within the clade composed of Piabina and Creagrutus. Piabina argentea and all Creagrutus species other than C. cracentis, C. gephyrus, and C. maxillaris have the anterior por- tion of the mesethmoid expanded ventrally into a relatively large, transversely flattened, vertical plate that projects down- ward from the ventral margin of the main body of the meseth- moid (Figure 14). Ventrally this process, herein termed the an- teroventral process of the mesethmoid, ranges from being somewhat rounded to nearly square in lateral view. It extends between the symphyseally expanded premaxillae and nearly separates these contralateral ossifications except for a limited degree of contact along their anterior and ventral margins. This form of ventrally expanded mesethmoid was not encountered in examined characiform outgroups and is consequently con- sidered to be derived. In Creagrutus cracentis, C. gephyrus, and C. maxillaris the premaxillae are narrower symphyseally than in their congeners (see comments under "Premaxilla," above). Associated with this proportionally reduced symphyseal contact of the con- tralateral premaxillae is a restructuring of the ventral portion of the anterior section of the mesethmoid into an anteroventrally oriented triangular process that again mostly separates the me- dial surfaces of the opposing premaxillae. Among examined outgroup characids only Gymnocharaci- nus bergi was found to have a form of anterior process of the mesethmoid reminiscent of that in Creagrutus cracentis, C. ge- phyrus, and C. maxillaris. The form of the process in the exam- ined Gymnocharacinus specimen (USNM 313878) is not as tri- angular as that illustrated by Miquelarena and Aramburu (1983, fig. 3), which more closely approximates the condition in the three Creagrutus species. Furthermore, the overall form of the mesethmoid in Gymnocharacinus bergi differs signifi- cantly from that in Creagrutus. Gymnocharacinus bergi also lacks both the series of distinguishing features of the Creagru- tus-Piabina clade and the synapomorphies for the clades within Creagrutus, which include C. cracentis, C. gephyrus, and C. maxillaris. These factors in combination lead us to hypothesize that the condition of the anterior process of the mesethmoid in Gymnocharacinus is nonhomologous with that in Creagrutus cracentis, C. gephyrus, and C. maxillaris. CHARACTER 35. State 0: Anterior portion of mesethmoid not as in 1. State 1: Anterior portion of mesethmoid expanded ventrally into a relatively large, transversely flattened, vertical plate. The main body of the mesethmoid in numerous characids, including Piabina and Creagrutus, has a ventromedial lamellar process, which contacts the dorsal surface of main body of the vomer, or a matching lamellar process extending dorsally from the median portion of vomer. This ventral lamellar process on the mesethmoid arises from the ventral surface of a varyingly developed median chamber that extends anteriorly within the mesethmoid to differing degrees. Examined tetragonopterine outgroups, including Piabina argentea, along with the majority of Creagrutus species, either lack the median chamber within the mesethmoid or have a vertically broad medial lamellar pro- cess separating the contralateral nasal capsules. A subset of Creagrutus species (C. amoenus, C. atratus, C. beni, C. boli- vari, C. brevipinnis, C. britskii, C. changae, C. cochui, C. NUMBER 613 31 ventrolateral process of mesethmoid lateral process of mesethmoid vomer anteroventral process of mesethmoid FIGURE 14.—Lateral view of anterior portion of mesethmoid in Creagrutus amoenus, USNM 311339, 65.0 mm SL; left premaxilla removed, right premaxilla in place, showing ventral expansion of anteroventral portion of mesethmoid; anterior to left. ephippiatus, C. figueiredoi, C. gyrospilus, C. holmi, C. hysgi- nus, C. kunturus, C. lepidus, C. machadoi, C. magdalenae, C. manu, C. melasma, C. menezesi, C, mucipu, C. occidaneus, C. ortegai, C. paraguayensis, C. paralacus, C. petilus, C. seduc- tus, C. taphorni, C. ungulus, C. vexillapinnus) has the dorsal portion of the lamellar plate expanded laterally to varying de- grees, with the expansion most pronounced posteriorly. The de- gree of expansion ranges from a limited lateral flaring along the posterior portion of the lamella to a pronounced expansion that extends as far anteriorly as the posterior margin of the lat- eral mesethmoid wing. Continuity across these different de- grees of expansion renders the subdivision of this mesethmoid expansion into different characters impossible, and the expan- sion, regardless of degree, is considered to be a single derived condition. CHARACTER 36. State 0: Mesethmoid without lateral ex- pansion of dorsal portion of lamellar plate. State 1: Meseth- moid with lateral expansion of dorsal portion of lamellar plate. FRONTAL.—The majority of characiforms have the frontals separated to varying degrees by the median fronto-parietal fon- tanel, with contact between the frontals sometimes limited to the transverse epiphyseal bar that divides the fontanel into an- terior and posterior portions. A well-developed fontanel sepa- rating the frontals is present in a variety of characiforms, in- cluding the basal distichodontid characiform Xenocharax (Daget, 1960, fig.7) and including Piabina argentea, the proxi- mate sister group to Creagrutus. In those taxa, the anterior por- tions of the frontals are only in contact through the epiphyseal bar. Seven Creagrutus species (C. atrisignum, C. cochui, C. lepidus, C. maracaiboensis, C. muelleri, C. ouranonastes, C. pila) have, instead, the anteromedial portions of the frontals in broad contact, which reduces the relative longitudinal extent of the anterior portion of the fontanel. In light of its generality within characiforms and its presence in Piabina, the more ex- tensive fontanel is considered to be primitive, and the increased contact of the contralateral frontals in the seven cited Creagru- tus species is considered to be derived. CHARACTER 37. State 0: Anterior portions of frontals not in contact anterior to fontanel. State 1: Anterior portions of fron- tals in contact anterior to fontanel. Contact of the frontals along their medial margins is most pronounced in C. maracaiboensis in which the fontanel ex- tends only a short distance anterior to the epiphyseal bar, an au- tapomorphic modification. This species also has the posterior portion of the fontanel significantly expanded laterally, with the opposing medial margins of the frontals distinctly further separated than in any congener or in Piabina argentea. Al- though C. maracaiboensis is one of the most diminutive spe- cies in Creagrutus in terms of maximum known body size, this frontal separation is apparently not a consequence of its small 32 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY size. The separation of the frontals in C nigrostigmatus, a sec- ond diminutive species, and juveniles of other Creagrutus spe- cies comparable in body size to adults of C. maracaiboensis lack an increased separation of the frontals lateral to the fon- tanel. Given its unique nature among Creagrutus species and its absence in outgroups, this modification is considered to be an autapomorphy for C. maracaiboensis. The laterosensory canal in the sixth infraorbital (dermosphe- notic) of characiforms typically communicates with the su- praorbital canal by a large opening in the latter canal located in the region above the dilatator fossa. Two forms of this opening occur in Creagrutus. In the first, the opening is located at the junction between the anterior process of the pterotic and the posteroventral portion of the frontal. This condition is consid- ered to be present if the pterotic in any way contributes to the margin of the opening (see Table 2 for listing of species with this condition). In the second condition, the opening into the supraorbital canal is entirely within the frontal, typically being well separated from the region of contact between the frontal and the pterotic along the supraorbital canal (see Table 2 for listing of species with this condition). Variability in this feature among tetragonopterine outgroups makes it impossible to po- larize this feature. CHARACTER 38. State 0: Opening in supraorbital canal for communication with laterosensory canal in sixth infraorbital at junction between anterior process of pterotic and posteroven- tral portion of frontal. State 1: Opening in supraorbital canal for communication with laterosensory canal in the sixth in- fraorbital entirely in frontal. PARIETAL.—The parietal branch of the supratemporal lat- erosensory canal in characids usually extends from the frontal across the lateral surface of the parietal to terminate on the pos- terior portion of the parietal; this morphology also is present in Piabina argentea, the sister group to Creagrutus. All but two Creagrutus species share that generalized morphology of the canal, albeit with some variation in the location of the posterior terminus of the canal segment. In C. maracaiboensis and C. ni- grostigmatus the parietal branch is either entirely lacking or is restricted to a very short segment immediately posterior to the junction of the frontal and parietal. Creagrutus maracaiboensis and C. nigrostigmatus are the smallest members of the genus as adults, and reduced adult body size often is correlated with a decrease in the development of the laterosensory canal system on the head and body (Weitzman and Vari, 1988:445). In C. maracaiboensis and C. nigrostigmatus the absence of the pari- etal canal is not apparently directly size-related because the ca- nal is fully developed in juveniles of other Creagrutus species at sizes comparable to those of adults of C. maracaiboensis and C. nigrostigmatus. CHARACTER 39. State 0: Parietal branch of supratemporal laterosensory canal extending from frontal to posterior portion of parietal. State 1: Parietal branch of supratemporal laterosen- sory canal either lacking or restricted to short segment immedi- ately posterior to frontal-parietal junction. Creagrutus maracaiboensis has the parietal portion of the fronto-parietal fontanel distinctly wider than in its congeners or Piabina argentea. This increased separation of the medial margins of the parietals is absent in examined outgroups and is considered to be autapomorphic for C. maracaiboensis. Al- though C. maracaiboensis is a diminutive among Creagrutus species in terms of maximum known body size, this increased separation of the parietals relative to the condition in its con- geners is apparently not correlated with small size. Neither the second diminutive Creagrutus species, C. nigrostigmatus, nor smaller specimens of other Creagrutus species have a compa- rable increased separation of the medial margins of parietals lateral to the fronto-parietal fontanel at body sizes equivalent to those of adults of C. maracaiboensis. DILATATOR GROOVE.—The dilatator groove is a variably de- veloped fossa that extends from the sphenotic spine onto the skull roof and involves, to different degrees, contributions from the sphenotic, frontal, and pterotic in different groups of characiforms (see comments by Weitzman, 1964:139; Roberts, 1969:408). In Creagrutus the groove extends onto the lateral surface of the sphenotic and frontal. The extent of the groove is limited dorsally by the ventral margin of the raised posterior portion of the supraorbital canal in the frontal and by the pterotic canal in the pterotic. In Piabina argentea and approxi- mately half of the species of Creagrutus the groove is not dor- sally roofed by either the frontal or the pterotic. Approximately half of the species of Creagrutus have ventrolateral plate-like extensions from the lateral margin of the posterior section of the supraorbital canal in the frontal and from the anterior por- tion of the pterotic canal. These extensions varyingly roof over the dilatator groove dorsolaterally (see Table 2 for listing of species with this condition). The degree of development of these extensions is particularly pronounced in examined speci- mens of C. atratus, C. ephippiatus, C. lassoi, C. paralacus, C. taphorni, and C. ungulus, but it is not scored as a further de- rived condition because of the intraspecific ontogenetic varia- tion in the expression of this feature and because of the range in size of examined specimens of the different species. A roofing over of the dilatator fossa was absent in both Piabina and other examined outgroup tetragonopterines, and its presence in a subset of Creagrutus species is considered to be derived. CHARACTER 40. State 0: Dorsolateral portion of dilatator groove not roofed over by processes from frontal and pterotic. State 1: Dorsolateral portion of dilatator groove roofed to vary- ing degrees by processes from frontal and pterotic. TEMPORAL FORAMEN.—An opening, the temporal foramen (Weitzman, 1962:24), is present in diverse characids, including Piabina argentea. This aperture is situated along the junction of the sphenotic and pterotic in the area ventral to the pterotic portion of the laterosensory canal joint (Figure 15; see also Weitzman, 1962, fig. 3, for opening in Brycon meeki). This fo- ramen is present in a subset of Creagrutus species, although it exhibits a notable range in relative size (see Table 2 for listing of species with this condition). The opening is lacking in all re- NUMBER 613 33 pterotic frontal sphenotic temporal foramen prootic FIGURE 15.—Lateral view of sphenotic and adjoining bones in Creagrutus hysginus, USNM 326055, 41.3 mm SL; left side, lateral view, anterior to left. maining species of Creagrutus, an apparently derived condi- tion given the broad occurrence of the temporal foramen in Pi- abina, the sister group to Creagrutus, and among examined outgroup tetragonopterines. CHARACTER 41. State 0: Temporal foramen present. State 1: Temporal foramen absent. SPHENOTIC.—The ventral portion of the sphenotic that bor- ders the prootic forms the anterior portion of the hyomandibu- lar fossa, which is the region of articulation of the dorsal por- tion of the hyomandibula with the cranium. Along its dorsal articular margin the hyomandibula in Piabina and Creagrutus is typically expanded laterally, resulting in a broadened area of contact between that bone and the cranium (see discussion un- der "Hyomandibula," above). Matching this expanded portion of the hyomandibula is a laterally expanded articular surface on the ventral portion of the sphenotic, with the anterior portion of the hyomandibular fossa mostly formed by the sphenotic (Fig- ure 15). This expansion of the sphenotic contribution to the hy- omandibular fossa results from the lateral expansion of the sphenotic in the region dorsal of the anterior portion of the hy- omandibula. Associated with this expansion of the sphenotic articular surface is a reorientation of the region of articulation to a more obtuse angle relative to the horizontal plane than oc- curs in examined characid outgroups. In addition, the plane of the articular surface on the sphenotic is rotated slightly out- ward. As a consequence, the anterior portion of the hyoman- dibular fossa on the sphenotic (and also the prootic) is visible in lateral view in both Piabina and Creagrutus. This contrasts with the typical characid condition in which the hyomandibular fossa is not readily visible in lateral view. The combination of these changes results in a form of the ventral portion of the sphenotic that is not found in examined outgToup characiforms; therefore, this form is judged to be derived. CHARACTER 42. State 0: Hyomandibular fossa not as in 1. State 1: Hyomandibular fossa visible laterally as a consequence of reorientation of that portion of sphenotic. In characiforms, the lateral surface of the sphenotic bears a strong sphenotic spine. The spine typically has a blade-like ventral portion that delimits the posterior margin of the orbit. This spine is most often unelaborated in characiforms, but in Piabina argentea and in Creagrutus species other than C. melanzonus, C. pearsoni, and C. zephyrus the distal portion of the lateral surface of this spine is variously elaborated posteri- orly. These extensions of the spine serve for the attachment of aponeurotic tissue sheets associated with adjoining muscles, and the presence of such processes is considered to be derived. CHARACTER 43. State 0: Sphenotic spine simple. State 1: Distal portion of lateral surface of sphenotic spine variously elaborated posteriorly. 34 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY Within the assemblage of species with such elaborated sphe- notic spines there is considerable diversity in the degree of de- velopment of these processes, both infra- and intraspecifically, and ontogenetically. This variability renders it impossible to unambiguously define discrete characters within most of this variation. Discrete modifications of that process occur in Crea- grutus gyrospilus, C. hysginus, and C. paralacus, which, in ad- dition to having distinct posteriorly directed processes extend- ing from the distolateral margin of the sphenotic spine, also have an anterior lamellar process along the lateral margin of the spine. This process contacts the anteroventral margin of the adjoining portion of the frontal, thereby enclosing a medial space. No such process has been encountered in examined out- groups, and its presence is considered to be derived. CHARACTER 44. State 0: Anterior margin of sphenotic spine unelaborated. State 1: Anterior margin of sphenotic spine with anterior lamellar process. In Creagrutus gephyrus the sphenotic spine is narrower ba- sally than in congeners and is shifted posterodorsally compared with the typical condition in that genus and in outgroup charac- ids. As a consequence, the base of the spine is distant from, rather than proximate to, the sphenotic component of the hyo- mandibular fossa. This shift also moves the spine well into the center of the basal portion of the dilatator grove, a condition not encountered elsewhere within Creagrutus or examined out- group characids. The form of the sphenotic spine is hypothe- sized to be an autapomorphy for the species. EPIOCCIPITAL.—The vast majority of characiforms are char- acterized by two pairs of posttemporal fossae situated at the posterolateral and dorsolateral margins of the posterior portion of the cranium (e.g., Brycon meeki; see Weitzman, 1962, figs. 3, 5). These two pairs of apertures are present in all Creagrutus species, but C. atratus, C. atrisignum, C. bolivari, C. britskii, C. cochui, C. figueiredoi, C. gracilis, C. meridionalis, and C. paraguayensis also have a third opening enclosed entirely within the epioccipital in the region medial to the tube for the posterior vertical semicircular canal. Various New and Old World characiforms have a third post- temporal fossa bordered, at least in part, by the epioccipital. An extensive, vertically ovate third posttemporal fossa bordered by both the exoccipital and epioccipital occurs in the New World characid subfamily Cynodontinae (Vari, 1979:289; Toledo- Piza, 1997) and in the African sister families Citharinidae and Distichodontidae (Vari, 1979, fig. 15). Given the contribution of the exoccipital to the fossa in these three families, these ap- ertures are judged to be nonhomologous with those in some species of Creagrutus. Phylogenetic information further indi- cates that neither the Cynodontinae (Lucena and Menezes, 1998, fig. 1; Toledo-Piza, 2000) nor Citharinidae and Distich- odontidae (Buckup, 1998:134) are closely related to the Tet- ragonopterinae, including Creagrutus. A third posttemporal fossa situated entirely within the epioc- cipital, such as occurs in the cited species of Creagrutus, is un- known elsewhere within the Characidae but is present in the Neotropical characiform families Curimatidae (Vari, 1983:37), Parodontidae (Roberts, 1974:425, fig. 59), and Hemiodontidae (Vari, 1979:416, fig. 5). The Curimatidae is most closely re- lated to the Prochilodontidae (Vari, 1983:47-48; Vari, 1989:51-52), with that clade, in turn, most closely related to a clade formed by the Anostomidae plus Chilodontidae (Vari, 1983:50). Prochilodontids, anostomids, and chilodontids all lack a third posttemporal fossa within the epioccipital, so the epioccipital fossa in curimatids is most parsimoniously hypoth- esized to be homoplastic to that in some species of Creagrutus. Buckup (1993:229; 1998:134) proposed that the phylogenetic relationships of the Parodontidae and Hemiodontidae lie with groups other than the subset of characid genera he examined. That evidence and the absence in both Piabina, the sister group to Creagrutus, and in various outgroup charicids of a posttem- poral fossa limited to the epioccipital leads us to hypothesize that its presence in a various Creagrutus species is derived, al- beit homoplastically present in some groups of noncharacid characiforms. CHARACTER 45. State 0: Third posttemporal fossa within epioccipital absent. State 1: Third posttemporal fossa within epioccipital present. VOMER.—The vomer in Creagrutus has a pair of openings for the passage of a nerve into the oral cavity. The orientation and relative size of this opening differ somewhat within the as- semblage formed by these genera, but only in two species, Cre- agrutus cracentis and C. maxillaris, do these openings differ dramatically from the condition in their congeners. In these two species the openings are relatively significantly larger and are located distinctly more anteriorly than in Piabina and other Creagrutus species; these modifications consequently are hy- pothesized to be derived conditions. CHARACTER 46. State 0: Not as in state 1. State 1: Open- ings in vomer for passage of nerve into oral cavity large and anteriorly located. PECTORAL GIRDLE MESOCORACOID.—The mesocoracoid in characiforms has a widened base that contacts the scapula and coracoid ventrally and extends slightly dorsolaterally to contact the medial sur- face of the cleithrum. The contact between the mesocoracoid and the medial surface of the cleithrum is varyingly reinforced by an expansion of the dorsal portion of the mesocoracoid into a broad plate, which is highly variable in form and is tightly joined to the medial surface of the cleithrum. In the basal characiform family Distichodontidae (Xenocharax spilurus, Nannocharax intermedius, Paradistichodus dimidiatus) the mesocoracoid is only slightly expanded dorsally. A greater ex- pansion of the dorsal portion of mesocoracoid occurs in various characiforms, including diverse characids, often with a ventral extension of this portion of the ossification along the medial surface of the cleithrum. NUMBER 613 35 cleithrum mesocoracoid scapula coracoid FIGURE 16.—Mesocoracoid, scapula, and adjoining bones in Creagrutus lepi- dus. USNM 325045, 40.3 mm SL; right side, medial view, anterior to right. This ventral expansion of the mesocoracoid extends towards, but is nearly always separate from, the medial portion of the scapula among examined characids, including Piabina. In the species of Creagrutus, in contrast, the ventrolateral extension of the mesocoracoid is further developed and contacts the dor- solateral margin of the scapula through a small intervening car- tilage (Figure 16). As a consequence, the scapula and mesoco- racoid in Creagrutus delimit an anteroposteriorly aligned passage through the pectoral girdle and exclude the cleithrum from the border of that opening, contrary to the typical characi- form condition. Given the lack of such scapula-mesocoracoid contact in outgroup characiforms the condition in Creagrutus is considered to be derived. Among examined characiform outgroups, only the characid genera Triportheus and Moojenichthys, sister groups according to Castro and Vari (1990), have contact between the ventrolat- eral margin of the mesocoracoid and the dorsolateral portion of the scapula. Moojenichthys was hypothesized to be most closely related to the monotypic fossil genus Lignobrycon and was placed into the synonymy of the latter genus by Malabarba (1998:78). We hereafter refer to Moojenichthys myersi as Li- gnobrycon myersi, but we have not examined specimens of the fossil L. ligniticus and cannot evaluate the contact, or lack thereof, between the ventrolateral margin of the mesocoracoid and the dorsolateral portion of the scapula in that species. Con- tact between the ventrolateral margin of the mesocoracoid and the dorsolateral portion of the scapula in the Lignobrycon-Tri- portheus clade is, however, the result of different modifications from those in Creagrutus. As noted, contact between these bones in Creagrutus is a consequence of a ventral extension of the dorsomedial portion of the mesocoracoid to meet the dorso- medial margin of the scapula. In Lignobrycon and Triportheus the ventral extension of the dorsomedial portion of the mesoco- racoid is absent. Rather, the entire scapula is tilted, bringing its dorsolateral margin into contact with the ventral margin of the mesocoracoid. This form of contact is nonhomologous with that between these bones in Creagrutus. The form of mesoco- racoid-scapula contact in Creagrutus is consequently consid- ered a synapomorphy for the species of that genus. CHARACTER 47. State 0: Ventrolateral portion of mesocora- coid not contacting dorsolateral margin of scapula. State 1: Ventrolateral extension of mesocoracoid contacting dorsolat- eral margin of scapula through a small intervening cartilage. SCAPULAR FORAMEN.—The scapular foramen in many characiforms, including Xenocharax, is an opening situated in the anterior portion of the scapula (e.g., Brycon meeki, Weitz- man, 1962, fig. 20). Anteriorly the border of the scapular fora- men is formed by a narrow bony ring that separates the fora- men from a more anterior opening delimited by the scapula, cleithrum, and coracoid. Given the broad occurrence of this an- terior ring of bone delimiting the anterior portion of the scapu- lar foramen among characids, the possession of such a ring-like process is considered to be plesiomorphic within the assem- blage consisting of Piabina and Creagrutus. The narrow ante- rior ring of bone forming the anterior portion of the scapular foramen is present in a number of Creagrutus species but is ab- sent both in Piabina argentea and various Creagrutus species (see Table 2 for a listing of the species with each character). The absence of a narrow anterior scapular ring is hypothesized to be the derived condition. CHARACTER 48. State 0: Scapula with narrow ring-like pro- cess forming anterior border of scapular foramen. State 1: Scapula lacking narrow ring-like process forming anterior bor- der of scapular foramen. CONTACT BETWEEN CORACOID AND CLEITHRUM.—The scapular foramen is separated by a narrow ring of bone from the more anteriorly positioned opening delimited by the scap- ula, coracoid, and cleithrum (Weitzman, 1962, fig. 5). This dis- tinct anterior opening occurs in diverse examined characids and characiforms, including Xenocharax, a member of the basal distichodontid-citharinid clade within characiforms. In Piabina and Creagrutus the opening situated at the junction of the scapula, coracoid, and cleithrum is eliminated as a conse- quence of the expansion of the cleithrum and particularly the coracoid into the opening plesiomorphically present in that re- gion. In the species of Creagrutus with a narrow anterior ring of the scapula forming the anterior portion of the scapular fossa, the portions of the cleithrum and coracoid immediately proximate to the ring contact and match the form of the anterior margin of the bony ring, consequently forming a concentric bony margin. When the narrow anterior bony ring of the scap- ula is lacking in Piabina and various Creagrutus species (see "Scapular Foramen," above) the expanded portions of the clei- thrum and coracoid form the anterior margin of the rounded 36 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY scapular foramen, with the remainder of the border of the open- ing formed by the scapula. Such an expansion of the cleithrum and coracoid was not encountered elsewhere in examined characiforms and is considered to be derived. CHARACTER 49. State 0: Opening delimited by the scapula, coracoid, and cleithrum present anterior to scapular foramen. State 1: Opening delimited by the scapula, coracoid, and clei- thrum anterior to scapular foramen lacking. FIRST POSTCLEITHRUM.—The presence of three postcleithra along the posterior margin of the pectoral girdle is typical for characiforms; however, these ossifications are lost in various combinations within the order. Postcleithrum 1, the dorsalmost of the series, is a variably shaped, flat, ossification located at the posteroventral margin of the supracleithrum and posterior of the cleithrum in Piabina argentea and most Creagrutus spe- cies. This ossification is, however, absent in eight Creagrutus species (C. crenatus, C. hildebrandi, C. lepidus, C. maracai- boensis, C. me las ma, C. peruanus, C. petilus, C. ungulus). All postcleithra are missing in the Gasteropelecidae (Weitz- man, 1954:226), and the first postcleithrum is missing in the African distichodontid characiforms Nannocharax Giinther and Hemigrammocharax Pellegrin (Vari, 1979:311) and in the Neotropical anostomid genera Synaptolaemus Myers and Fernandez-Yepez and Sartor Myers and Carvalho (Winterbot- tom, 1980:46). The distichodontid and anostomid genera lack- ing postcleithrum 1 are deeply embedded within the phylogeny of groups otherwise characterized by the presence of that ossi- fication (see Vari, 1979, and Winterbottom, 1980, respec- tively). Furthermore, available evidence (Vari, 1979; Buckup, 1998) indicates that the relationships of distichodontid and anostomid taxa lie with clades distant from that including Cre- agrutus. The relationships of the Gasteropelecinae within the Characiformes are still uncertain, although Orti and Myer (1997) found that molecular data aligned the subfamily with taxa other than those presently assigned to the Tetragonopteri- nae. The Gasteropelecinae also lacks the synapomorphies for the Creagrutus+Piabina clade and for Creagrutus. Thus, the absence of postcleithrum 1 in a subset of Creagrutus is hypoth- esized to be derived and homoplastic relative to the lack of this ossification in the cited outgroups. CHARACTER 50. State 0: First postcleithrum present. State 1: First postcleithrum absent. SQUAMATION LATERAL LINE.—Creagrutus maracaiboensis is unique among the species of Creagrutus in having laterosensory canal pores limited to the anterior eight to 10 scales of the lateral line scale series. This reduction in the extent of lateral line poring contrasts with the completely pored lateral line series in all the remaining species in the clade, which is the typical condition within characiforms. This apomorphic reduction is, however, a common paedomorphic feature associated with miniaturization in various teleostean fishes (Myers, 1958:29; Weitzman and Vari, 1988:445). Paedomorphosis as an explanation for the truncated lateral line in C. maracaiboensis is compromised, at least to some degree, by the presence of a completely pored lat- eral line in C. nigrostigmatus, a species with a body size com- parable to that in C. maracaiboensis. Harold and Vari (1994:7) noted that two trans-Andean spe- cies, Creagrutus nigrostigmatus and C maracaiboensis, have unusually low numbers of lateral line scales (30-32, and 29- 31 lateral line scales, respectively) that compare with the 33 to 41 scales in their trans-Andean congeners. Those authors tenta- tively proposed that this low lateral line scale count might rep- resent a synapomorphy for that species pair, but they refrained from a definitive statement pending a thorough examination of that feature in the cis-Andean Creagrutus species. Analysis has shown that cis-Andean Creagrutus species have 34 to 45 lateral line scales. This range does not overlap that of C. nigrostigma- tus and C. maracaiboensis. Given the higher number of lateral line scales in Piabina argentea and in other outgroup taxa, we hypothesize that the lower number of lateral line scales in C. nigrostigmatus and C. maracaiboensis is derived. CHARACTER 51. State 0: Possession of 33 or more lateral line scales. State 1: Possession of 29 to 32 lateral line scales. LATERAL LINE SCALE FORM.—The scales of the lateral line in Creagrutus caucanus have a form of the aperture into the sensory pore that is unique in Creagrutus and, indeed, that has not been encountered elsewhere among characiforms. In C caucanus there is a lateral lamellar process overlying the sen- sory pore. This shelf-like process is formed by an abrupt poste- rior expansion of the posterior ostium on the lateral line canal in each scale (see Harold and Vari, 1994, fig. 3), an autapomor- phy for the species. POST-ANAL SCALES.—The position of the anus relative to the anal-fin origin demonstrates a degree of variation within Creagrutus. The vast majority of species within Creagrutus have two median scales between the posterior margin of the anus and the point where the anteriormost anal-fin ray exits from the body. This condition also is found in Piabina and many other tetragonopterines and is consequently hypothesized to be primitive. Creagrutus amoenus and C. kunturus have, in- stead, only one median scale in the region, whereas three spe- cies have a higher number of post-anal median scales, which is a derived condition. Four post-anal scales occur in C. ungulus and five scales are found along the post-anal midline in C. cra- centis and C. maxillaris. Proximity of the anus and anterior anal-fin rays is typical in characid outgroups, and the increased separation between these structures in these three species is hy- pothesized to be derived, although the overall most parsimoni- ous hypothesis of intrageneric relationships indicates that the increased number of post-anal scales in C. cracentis and C. maxillaris was arrived at independently of that in C. ungulus. CHARACTER 52. State 0: Post-anal scales 1 or 2. State 1: Post-anal scales 4 or 5. NUMBER 613 37 PIGMENTATION Creagrutus species differ in a number of details of pigmenta- tion. Much of this variation, most notably that involving the humeral mark, presents problems both in definition and polar- ization. Some components of body and fin pigmentation are, however, discrete and phylogenetically informative. DORSAL-FIN PIGMENTATION.— Although various Creagru- tus species have some dark pigmentation on the dorsal fin, only C. vexillapinnus has a discrete patch of dark pigmentation over- lying the central portions of the fin rays. In light of the lack of such pigmentation in its congeners and Piabina, such pigmenta- tion is considered to be autapomorphic for C. vexillapinnus. CAUDAL-FIN PIGMENTATION.—The caudal fin among Crea- grutus species bears varying areas of dark pigmentation. Crea- grutus ouranonastes is unique within the genus in having the dark caudal-fin pigmentation concentrated into two small, very dark spots bordering the middle ray of the caudal fin. This fea- ture is hypothesized to be an autapomorphy of the species be- cause of its absence in congeners and Piabina, the first out- group to Creagrutus. HUMERAL MARK FORM.—The humeral mark is highly vari- able within Creagrutus, with most members of the genus hav- ing a rotund mark or having the mark developed vertically to varying degrees. The intrageneric continuity within the hu- meral variation renders it impossible to nonarbitrarily discrimi- nate character states, and only the most discrete conditions are incorporated into the phylogenetic analysis. The vertically elongate humeral spot is common to Piabina, the majority of Creagrutus species, and many outgroup tetragonopterines; therefore, that condition is assumed to be plesiomorphic within Creagrutus. Creagrutus atrisignum and C. cochui have horizontally elon- gate main bodies of the humeral marks. This form is hypothe- sized to be derived compared with the rotund or vertically elon- gate form of the mark in most congeners and the immediate outgroup Piabina. CHARACTER 53. State 0: Humeral mark rotund or vertically elongate. State 1: Humeral mark horizontally elongate. Associated with the horizontal elongation of the main body of the humeral spot in C. atrisignum is the presence of a sec- ondary patch of dark pigmentation situated dorsal of the main body of the humeral mark. The degree of development of the dorsal spot varies intraspecifically. In some specimens of C. atrisignum there is a vertical component of the dorsal spot that extends ventrally to approach or contact the main body of the humeral spot. The presence of such a secondary component of the humeral mark is unique and is considered to be autapomor- phic for C. atrisignum. MlDLATERAL BODY PIGMENTATION.—Among Creagrutus species, only C. mucipu of the Rio Tocantins basin has midlat- eral body pigmentation consisting of a series of posteriorly convex, dark, midlateral chevron-shaped spots. Such pigmenta- tion is rare in characiforms. This pattern is hypothesized to be an autapomorphy for C. mucipu. Although many Creagrutus species have a stripe of dark pig- mentation extending to differing degrees anteriorly from the base of the caudal fin, in only three species does the stripe ex- tend, in at least some individuals, the entire length of the body. Such a midlateral band of dark pigmentation is, however, achieved by two different methods within the genus. Creagrutus lepidus has a broad, continuous band of dark pig- mentation extending between the supracleithrum and the base of the middle caudal-fin rays. The stripe, which apparently sub- sumes the humeral mark, is well developed in all examined specimens, including those as small as 32.7 mm SL. As noted by Vari et al. (1993:352), this form of midlateral stripe is unique to C. lepidus within Creagrutus. The second form of well-developed, dark, midlateral pig- mentation occurs in Creagrutus amoenus and C. kunturus. Al- though larger individuals of both species have midlateral stripes that are somewhat reminiscent of, albeit not as continu- ous as, the stripe in C. lepidus, such pigmentation patterns are not general for either species. Smaller specimens of C. amoe- nus and C. kunturus, which are comparable in size to the known size range of C. lepidus, have patterns of dark spots ar- ranged along the midlateral surface of the body. There is a gen- eral, although by no means universal, ontogenetic trend of spot coalescence in both C. amoenus and C. kunturus. In some larger specimens, often those from acidic dark waters, the de- gree of coalescence is such that a nearly solid midlateral stripe results. Although the midlateral stripe in these species differs from, and thus is considered to be nonhomologous with that in C. lepidus, the pattern of a series of dark midlateral spots on the body in C. amoenus and C. kunturus is unique among Creagru- tus species, is lacking in Piabina, and is atypical among characids and is thus considered to be derived. CHARACTER 54. State 0: Midlateral body pigmentation not as in State 1. State 1: Midlateral body pigmentation consisting of series of dark spots that progressively coalesce ontogeneti- cally, sometimes forming midlateral stripe in adults. MISCELLANEOUS EPURALS.—The number of epurals varies among Creagrutus species, although most species have either one or two elements (see Table 2 for listing of species with each count). Rare indi- vidual variants of C. gyrospilus have three epurals, otherwise the species has two epurals. Available evidence does not permit us to polarize this character in the absence of a definitive sec- ondary outgroup. CHARACTER 55. State 0: 1 epural present. State 1: 2 or 3 epurals present. VERTEBRAE.—In their treatment of the Trans-Andean Crea- grutus species Harold and Vari (1994:7) noted that two species, C. nigrostigmatus and C. maracaiboensis, had unusually low numbers of vertebrae (32 or 33 in each species), which con- trasts with the 34 or more vertebrae in their trans-Andean con- geners. Harold and Vari (1994) tentatively proposed that this 38 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY low vertebral number might be a synapomorphy for the species pair, but they refrained from a definitive hypothesis pending a thorough examination of the much more speciose cis-Andean assemblage of Creagrutus species. Analysis has shown that the cis-Andean species of Creagrutus have 34 to 43 vertebrae, which does not overlap that for C. nigrostigmatus and C. mara- caiboensis. Given the high number of vertebrae in cis-Andean Creagrutus, in Piabina argentea (the immediate outgroup to Creagrutus), and in other outgroup taxa, we hypothesize that the lower vertebral numbers in C. nigrostigmatus and C. mara- caiboensis are derived. CHARACTER 56. State 0: Possession of 34 or more verte- brae. State 1: Possession of 32 or 33 vertebrae. NOTOCHORDAL MINERALIZATIONS.—The notochord in characiforms, including the species of Piabina and Creagrutus, extends posterodorsally past the uroneurals (only one pair present in these two genera) for a moderate distance beyond the hypural fan. The distal portion of the notochord is bordered dorsally, distally, and ventrally by the opisthural cartilage. Uniquely among the species of Creagrutus, three species, C. atratus, C. bolivari, and C. magoi, have one or more dense, mineralized bodies embedded within the laterally visible distal portion of the notochord. These structures, which have a granu- lar appearance, irregular margins, and stain deeply with al- izarin red, evidently are comparable to the structures that Arra- tia and Schultze (1992, figs. 13, 21) identified as being a "mineralization of the notochord not forming a chordacen- trum." Such mineralizations of the notochord are absent in Pia- bina argentea and in other examined outgroup characiforms, and their presence is thus considered to be derived within Crea- grutus. CHARACTER 57. State 0: Notochordal mineralizations ab- sent. State 1: Notochordal mineralizations present. Phylogenetic Reconstruction The strict consensus tree for the 61 species included in the analysis {Piabina argentea and 60 species of Creagrutus) was based on 1531 trees and had a consistency index (CI) of 0.40 and a resolution index (RJ) of 0.66. As might be expected given the relatively low CI, the degree of resolution of the tree was relatively poor. The resolution does, however, permit us to ad- dress the question of the diagnosable genera within this assem- blage. The strict consensus tree is presented in Figure 17. Char- acter numbers in the listing of synapomorphies for the various clades match those in the "Character Description and Analy- sis," above, and letters on Figure 17 indicate clades discussed in the text. MONOPHYLY OF THE Creagrutus AND Piabina CLADE (Fig- ure 17, Clade A).—Some evidence pertinent to the hypothesis of the monophyly of the clade formed by Creagrutus and Pia- bina was previously discussed by Van and Harold (1998). The following list summarizes that information and the additional synapomorphies discovered during this study. Piabina argentea nigrostigmatus maracaiboensis muelleri ournanonastes peruanus maxillaris cracentis gephyrus amoenus kunturus petilus lepidus cochui figueiredoi affinis meridionalis pearsoni crenatus melasma remaining species Creagrutus FIGURE 17.—Consensus tree of relationships of the genera Piabina and Crea- grutus and within Creagrutus. "Remaining species" represents an unresolved multitomy of 41 Creagrutus species not cited in the cladogram. Letters repre- sent nodes of clades discussed in the text. 1. Dentigerous surface of premaxilla triangular from ventral view (character 1). Reversed in clade consisting of Crea- grutus cracentis, C. gephyrus, and C. maxillaris; see syn- apomorphy 44. 2. Ligament between posteroventral corner of premaxilla and anterior surface of maxilla well developed (character 10). 3. Anterior terminus of dentary dentition distinctly posterior of anterior terminus of premaxillary dentition (character 13). Reversed in clade consisting of Creagrutus cracentis and C. maxillaris; see synapomorphy 46. 4. Ectopterygoid and quadrate not in contact (character 21). Reversed in Creagrutus mucipu. 5. Dorsal articular surface of hyomandibula asymmetrical; hyomandibula with dorsolateral buttress (character 27). Reversed in clade consisting of Creagrutus cracentis, C. gephyrus, and C. maxillaris; see synapomorphy 51. 6. Anterior portion of mesethmoid expanded ventrally into a relatively large, transversely flattened, vertical plate (character 35). Reversed in clade consisting of Creagru- tus cracentis, C. gephyrus, and C. maxillaris; see syna- pomorphy 52. NUMBER 613 39 7. Hyomandibular fossa visible laterally as a consequence of the reorientation of that portion of the sphenotic (char- acter 42). 8. Distal portion of the lateral surface of the sphenotic spine variously elaborated posteriorly (character 43). Reversed independently in each of Creagrutus melanzonus, C. pearsoni, and C. zephyrus. 9. Opening delimited by the scapula, coracoid, and clei- thrum anterior to scapular foramen lacking (character 49). 10. Two or 3 epurals present (character 55). Independently reversed to 1 epural in C. bolivari, C. lassoi, C. ma- chadoi, C. maxillaris, C. melanzonus, C. phasma, C. zephyrus, and clade formed by C. lepidus and C. petilus; see synapomorphy 63. The following are ambiguously optimized for this clade: 11. Anterior portion of the laterosensory canal segment in first infraorbital reaching or extending beyond anterior margin of bone (character 29). Either derived at this level and secondarily lost in Piabina or a synapomorphy for the members of Creagrutus. 12. Posterior portion of the first infraorbital overlapping the anterior portion of the second infraorbital (character 30). Either derived at this level and secondarily lost in Pia- bina and in three species of Creagrutus or a synapomor- phy for the members of the latter genus with secondarily loss in those same three species. 13. Opening in supraorbital canal for communication with laterosensory canal in the sixth infraorbital entirely in frontal (character 38). Either derived at this level with secondarily loss in C. affinis and C. meridionalis and sec- ondarily lost in Piabina, or a synapomorphy for the spe- cies of Creagrutus with secondarily loss in C. affinis and C. meridionalis. MONOPHYLY OF Piabina (Figure 17, Clade B).—Two de- rived features were found to diagnose Piabina, one of which (synapomorphy 14) is unique to the genus in the Creagrutus- Piabina clade and rare among characiforms. The ambiguously optimized characters for Creagrutus+Piabina (11-13) also could involve secondarily derived losses for Piabina. 14. Fourth infraorbital approximately triangular and excluded from posterior margin of infraorbital series in medium- to large-sized individuals (character 31). 15. Scapula lacking the narrow ring-like process forming the anterior border of the scapular foramen (character 48). MONOPHYLY OF Creagrutus (Figure 17, Clade C).—The fol- lowing includes both the synapomorphies for the species of Creagrutus proposed by Vari and Harold (1998) and additional synapomorphies discovered during this study. 16. Maxilla with anterior process thick and posterior portion robust (character 5). Reversed in clade formed by C. cra- centis and C. maxillaris; see synapomorphy 56. 17. Maxilla with distinct flexion in region where it extends past the posterior limit of the premaxilla (character 6). 18. Primordial ligament variably rotund in cross section and attaching primarily to distal one-half of maxilla (charac- ter 8). Further developed in clade consisting of C. amoe- nus and C. kunturus; see synapomorphy 41. 19. Distinct ligament extending between the anterodorsal tip of the maxilla and the dorsal surface of the premaxilla (character 11). 20. Ligament extending between midventral portion of as- cending process of maxilla and dorsal surface of premax- illa present (character 12). 21. Anguloarticular horizontally foreshortened (character 19). 22. Mesopterygoid and metapterygoid separate (character 22). Reversed in C. gephyrus. 23. Quadrate with variably developed vertical ridge or pro- cess extending dorsal ly from the main body of the quad- rate in, and posterior to, the region where the posterodor- sal process of the quadrate contacts the anteroventral process of the metapterygoid (character 25). Reversed in C. lepidus. 24. Anterior margin of hyomandibula anteriorly expanded and extending over posterodorsal region of metaptery- goid (character 26). 25. Temporal foramen absent (character 41). Reversed in clade consisting of C. cracentis, C. gephyrus, and C. maxillaris (synapomorphy 54), clade formed by C. lepi- dus and C. petilus (synapomorphy 60), clade consisting of C. cochui and C. figueiredoi (synapomorphy 64), and independently in some other Creagrutus species. 26. Ventrolateral extension of mesocoracoid contacting the dorsolateral margin of the scapula through a small inter- vening cartilage (character 47). The following characters are equivocally optimized at this level. 27. Anterior portion of the laterosensory canal segment in first infraorbital reaching or extending beyond anterior margin of bone (character 29). Either derived at this level or at level of Creagrutus plus Piabina. 28. Posterior portion of the first infraorbital overlapping the anterior portion of the second infraorbital (character 30). Either derived at this level and secondarily lost in some Creagrutus or gained at level of Creagrutus plus Piabina with secondary losses. 29. Scapula lacking narrow ring-like process forming ante- rior border of scapular foramen (character 48). Also equivocal at level of Creagrutus plus Piabina with sec- ondarily losses in Creagrutus. 1NTRAGENERIC RELATIONSHIPS WITHIN Creagrutus — Two basal clades within Creagrutus are defined by the characters examined in this study. One consists of C. maracaiboensis and C. nigrostigmatus (Figure 17, Clade D) and the other clade in- cludes all of the remaining species in the genus (Figure 17, 40 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY Clade E). Synapomorphies for C. maracaiboensis and C. ni- grostigmatus (Clade D) are as follows: 30. Metapterygoid foramen open posteriorly (character 23). Feature independently present in C. zephyrus. 31. Parietal branch of supratemporal laterosensory canal ei- ther lacking or restricted to short segment immediately posterior to frontal-parietal junction (character 39). 32. Scapula lacking narrow ring-like process forming ante- rior border of scapular foramen (character 48). Indepen- dently achieved elsewhere in Creagrutus (synapomor- phies 58, 61, 68). 33. Possession of 29 to 32 lateral line scales (character 51). 34. Possession of 32 or 33 vertebrae (character 56). The clade consisting of all other Creagrutus species (Clade E) is defined by the following synapomorphies: 35. Dentigerous portion of fifth ceratobranchial smaller and rotund, meeting main shaft of ossification approximately at distinctly acute angle (character 33). 36. Dorsolateral portion of dilatator groove roofed to varying degrees by processes from frontal and pterotic (character 40). Reversed in various species within the clade. Synapomorphies 35 and 36 define a clade that consists of a multitomy between C. muelleri, C. ouranonastes, and C. peru- anus and a clade (Figure 17, Clade F) that includes the majority of the species of Creagrutus. Clade F is defined by the follow- ing synapomorphies. 37. Primary tooth row on premaxilla without distinctly larger gap between first and second teeth (character 2). Re- versed independently in C. melanzonus and C. runa. Condition uncertain in C. cracentis and C. maxillaris. 38. Anterior tooth of premaxillary tooth triad positioned dis- tinctly posterior of first and second teeth of primary se- ries (character 3). Reversed independently in C. melanzo- nus and C. runa. Condition uncertain in C. cracentis and C. maxillaris. 39. Primordial ligament ventrally bifurcating, with attach- ments ventral ly to both the lateral surface of the angu- loarticular and lateral margins of the shelf-like lateral process of the quadrate (character 9). 40. Mesethmoid with lateral expansion of dorsal portion of lamellar plate (character 36). Reversed in various spe- cies. The clade defined by characters 37 to 40, which includes the majority of Creagrutus species, is poorly resolved internally. Four clades of two species and three clades of three species form a multitomy with the remaining 41 species of Creagrutus that are indicated as "Remaining species" in Figure 17. The first of these clades, consisting of C. cracentis, C. gephyrus, and C. maxillaris, is defined by 11 characters, five of which are uniquely derived. The sister-species pair C. cracentis and C. maxillaris share five synapomorphies, two of which are unique to that clade. The second clade formed by C. amoenus and C. kunturus is defined by three synapomorphies, two of which are unique to this lineage. Both of these clades consistently ap- peared in various analyses, both those involving all the charac- ters and those with the subtraction of various characters with high levels of homoplasy. The remaining four clades are de- fined by one to four optimized synapomorphies involving both homoplasies and reversals and often are not present when vari- ous characters with high levels of homoplasy are excluded from the analysis. The clades and their defining characters are given below. The first of the clades in this assemblage (Figure 17, Clade G) consists of three species, C. cracentis, C. gephyrus, and C. maxillaris, that share the following synapomorphies, all of which are either unique to this lineage or are uniquely reversed within Creagrutus: 41. Dentigerous surface of premaxilla longitudinally elongate from ventral view (character 1). Reversal of synapomor- phy 1. 42. Maxilla with 7 to 12 teeth (character 7). 43. Anterior terminus of dentary dentition not distinctly pos- terior of anterior terminus of premaxillary dentition (character 13). Reversal of synapomorphy 3. 44. Dentary foramen aligned directly transversely, with hori- zontally elongate lateral opening (character 14). 45. Medial opening of midlateral dentary foramen located immediately anterior to tip of meckelian cartilage (char- acter 15). 46. Dentary teeth 10 to 12 (character 17). 47. Anterior dentary teeth with 5 cusps (character 18). 48. Dorsal articular surface of hyomandibular nearly sym- metrical; hyomandibula without dorsolateral buttress (character 27). Reversal of synapomorphy 5. 49. Anterior portion of mesethmoid not expanded ventrally into a relatively large, transversely flattened, vertical plate (character 35). Reversal of synapomorphy 6. 50. Mesethmoid without lateral expansion of dorsal portion of lamellar plate (character 36). 51. Temporal foramen present (character 41). Reversal of sy- napomorphy 25. Within the clade formed by these three species, the subclade (Clade H) consisting of C. cracentis and C. maxillaris is de- fined by the following synapomorphies: 52. Single tooth lateral to primary premaxillary tooth row ab- sent (character 4). Independently lost within Creagrutus in C. molinus. 53. Maxilla with anterior process relatively slender and pos- terior portion transversely compressed (character 5). Re- versal of synapomorphy 16. 54. Margin of posterodorsal portion of anguloarticular dis- tinctly anterodorsally angled (character 20). 55. Openings in vomer for passage of nerve into oral cavity large and anteriorly located (character 46). NUMBER 613 41 56. Post-anal scales 4 or 5 (character 52). Independently present in Creagrulus in C. ungulus. The clade consisting of Creagrutus amoenus and C. kunturus (Clade I) is defined by the following synapomorphies, two of which are unique to these species in the genus: 57. Primordial ligament distinctly rotund in cross section and extending ventrally nearly to distal tip of maxilla (char- acter 8). Further development of synapomorphy 18. 58. Scapula lacking narrow ring-like process forming ante- rior border of scapular foramen (character 48). Feature independently acquired elsewhere in Creagrutus (syna- pomorphies 32, 61, 68). 59. Midlateral body pigmentation consisting of a series of dark spots that progressively coalesce ontogenetically, sometimes forming a midlateral stripe in adults (charac- ter 54). The Creagrutus lepidus and C. petilus clade (Clade J) is de- fined by the following synapomorphies, none of which are unique to this group: 60. Temporal foramen present (character 41). Reversal of sy- napomorphy 25. 61. Scapula lacking narrow ring-like process forming ante- rior border of scapular foramen (character 48). Process independently lost elsewhere in Creagrutus (synapomor- phies 32, 58, 68). 62. First postcleithrum absent (character 50). Also lost inde- pendently in some other Creagrutus species. 63. 1 epural present (character 55). Reversal of synapomor- phy 10. The clade formed by C. cochui and C. figueiredoi (Clade K) is defined by two features, neither of which is unique to these species in Creagrutus: 64. Temporal foramen present (character 41). Reversal of sy- napomorphy 25. 65. Third posttemporal fossa within epioccipital present (character 45). Also in other Creagrutus species. The clade formed by C. affinis, C. meridional is, and C. pear- soni (Clade L) is defined by the following two synapomor- phies, neither of which is unique to this group of species within Creagrutus. 66. Opening in supraorbital canal for communication with laterosensory canal in sixth infraorbital at junction be- tween anterior process of pterotic and posteroventral por- tion of frontal (character 38). Reversal of synapomorphy 13. 67. Dentition on third infrapharyngobranchial present (char- acter 34). Also present independently in other Creagru- tus species. Within this clade, C. affinis is hypothesized to be sister spe- cies of C. meridional is (Clade M) based on the following equivocal synapomorphy: 68. Scapula lacking narrow ring-like process forming ante- rior border of scapular foramen (character 48). Indepen- dently gained elsewhere in Creagrutus (synapomorphies 32,58,61). The final clade consisting of C. crenatus and C. melasma (Clade N) is defined by one synapomorphy: 69. First postcleithrum absent (character 50). Also lost inde- pendently in some other Creagrutus species. As noted above, the lineage indicated as "remaining species" on Figure 17 consists of 41 species of unresolved relationships within the consensus tree. PHYLOGENETIC POSITION OF Creagrutus molinus, C. plan- quettei, C. veruina, AND C. xiphos.—Among the numerous previously undescribed species discovered during the course of this study was one very distinctive form from the Rio Tocantins basin, Creagrutus molinus, known only from a single specimen herein designated as the holotype for the species. Creagrutus veruina and C. xiphos, although known from a larger number of specimens, are not represented by a sufficiently large sample size or by specimens in appropriate condition to permit the preparation of cleared and counterstained specimens. Creagru- tus planquettei was described by Gery and Renno (1989) on the basis of a limited type series, and we have been unsuccessful in locating other specimens of the species. In the absence of addi- tional specimens of these four species that we can clear and counterstain for cartilage and bone, our phylogenetic analysis is limited to the externally obvious features of C. molinus, C. planquettei, C. veruina, and C. xiphos. Creagrutus mucipu, C. planquettei, C. veruina, and C. xi- phos share several externally obvious features diagnostic of the clade consisting of Piabina and Creagrutus or subunits of Cre- agrutus. In each species, the lower jaw is foreshortened, which is a derived feature diagnostic for the clade consisting of Pia- bina and Creagrutus (see discussion under "Dentary," above). Similarly, these four species apparently have the derived broad- ened form of the premaxilla in ventral view, which is common to Creagrutus and Piabina. Furthermore, all four species share the arrangement of the primary premaxillary tooth series and the triangular cluster of large teeth lying medial to it, which are characteristic of both Piabina and the majority of Creagrutus species (see description under "Premaxillary Teeth," above, and see Gery and Renno, 1989, fig. 3, showing arrangement of the premaxillary teeth in C. planquettei). The arrangement of the premaxillary dentition in these four species is further informative at less inclusive phylogenetic levels. All four of these species have the triangular cluster of teeth situated entirely posterior of the primary row of premaxil- lary teeth, with the anterior teeth of the triangular cluster not entering into a gap in the arch of the primary series (see Gery 42 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY and Renno, 1989, fig. 3, for C. planquettei). This arrangement of these components of the premaxillary dentition is hypothe- sized to be derived features (synapomorphies 37, 38) delimit- ing a subunit within Creagrutus. In summary, Creagrutus mucipu, C. planquettei, C. veruina, and C. xiphos share three of the synapomorphies for the clade consisting of Creagrutus and Piabina and share one derived character defining a subunit of Creagrutus, but they lack the defining features for Piabina. We consequently assign these four species to Creagrutus, although we are presently unable to resolve their phylogenetic position within that genus. COMMENTS ON Piabarchus Myers.—Eigenmann (in Eigen- mann et al., 1914:8-9) described Piabina anal is from a single specimen collected at "Caceres" (=Sao Luiz de Caceves in the upper Rio Paraguay basin; Eigenmann and Myers, 1929:432). Eigenmann's brief original description of Piabina analis pro- vided scant insight as to the basis for this generic assignment other than describing the species as having a "mouth as in Cre- agrutus, anal [fin] long" and noting that the "scales [are] as in argenteus" (=Piabina argentea, the type species of Piabina; bracketed insertions ours). Myers (1928:90), in a brief discus- sion, pointed out that P. analis "differs from all known species of Piabina in the long, anteriorly inserted, anal fin" and com- mented on the similarity of P. analis to "certain Bryconameri- cus species." Myers also noted that Piabina had in common with Creagrutus "massive dentition," presumably implying that the feature was absent in Piabina analis, and he proposed a new genus, Piabarchus, for that species. Eigenmann and Myers (1929:432) commented that "Piabarchus is certainly more enti- tled to recognition as distinct from Piabina than Piabina is from Creagrutus" but did not delve further into the question of relationships. Most recently Mahnert and Gery (1988:1) de- scribed a second Piabarchus species (P. torrenticola) and re- considered the question of the relationships of the genus but were unable to resolve that issue. Our examination of a series of specimens of Piabarchus analis (USNM 326384) and P. torrenticola (USNM 326536) revealed that both species lack the derived features for the Creagrutus-Piabina lineage. Most notably, neither species has the massive dentition arranged in three series on the premax- illa, the form of dentition common to both Creagrutus and Pi- abina, but instead have the premaxillary teeth arranged in the pattern typical of many characids (see Mahnert and Gery, 1988, pi. 1: figs. 4-6, pi. 2: fig. 11, for illustrations of premax- illary dentition in Piabarchus analis and P. torrenticola, re- spectively). Piabarchus species similarly lack the distinctly foreshortened dentary of Piabina and Creagrutus. Although the dentary teeth of the two Piabarchus are somewhat en- larged anteriorly, such as occurs in various characids, they are not proportionally as massive as are those in Piabina and Cre- agrutus (compare Figure 9 herein with illustrations of lower jaw in Mahnert and Gery, 1988, pis. 1, 2). Neither does either of the species of Piabarchus possess the other derived features characteristic of the Piabina-Creagrutus assemblage. Finally, the species of Piabarchus also have a fourth infraorbital that broadly contributes to the posterior margin of the infraorbital ring. This is the plesiomorphic characiform condition, which contrasts with the condition in Piabina in which the posteri- orly tapering fourth infraorbital is excluded from the posterior margin of the infraorbital series, an autapomorphy for the ge- nus Piabina. Mahnert and Gery (1988:1) were unable to advance a defini- tive statement on the phylogenetic relationships of Piabarchus, noting that its "affinities with the genus Bryconamericus... are difficult to determine" (our translation). Our results are no more informative on this matter, but they do indicate that the relationships of Piabarchus lie outside of the Creagrutus-Pia- bina assemblage. Indeed, given the form of the jaws and the upper- and lower-jaw dentition in Piabarchus analis, which differ significantly from those in Creagrutus (and Piabina), it is not apparent why Eigenmann (in Eigenmann et al., 1914:8) stated that Piabina analis had the "mouth as in Creagrutus" and assigned the genus to Piabina. Genus Creagrutus Gunther Creagrutus Gunther, 1864:339 [type species Leporinus mulleri Gunther, 1859: 92, by monotypy; gender masculine]. Creagrudite Myers, 1927:117 [type species Creagrudite maxillaris Myers, 1927:118, by original designation; gender masculine]. Creagrutops Schultz, 1944:327 [type species Creagrutops maracaiboensis Schultz, 1944:327, by original designation; gender masculine]. DIAGNOSIS.—Creagrutus is diagnosed on the basis of a se- ries of synapomorphies listed under "Monophyly of Creagru- tus," above. Externally, the foreshortened lower jaw and the premaxillary teeth arranged in either of the patterns shown in Figures 1-3 combined with a fourth infraorbital whose poste- rior margin contributes to the posterior margin of the infraor- bital series distinguishes the species of Creagrutus within characiforms. Two exceptions to this generality are C. cracen- tis and C. maxillaris, species with highly derived dentition (FiguFe 4) but sharing a series of synapomorphies with their congeners and within subclades of Creagrutus (Figure 17). STATUS OF Creagrutus, Piabina, Creagrudite, AND Creagru- tops.—Our introductory remarks detailed the differing opin- ions concerning the generic limits of Creagrutus. During the last century, Piabina has variably been recognized as a distinct genus or as a synonym of Creagrutus by diverse authors (see "Remarks" under "Genus Piabina Reinhardt" for a detailed discussion). Such decisions either were unexplained or were focused on a single character system, the number of anal-fin rays that was purported to distinguish Piabina from Creagru- tus. Mahnert and G6ry (1988) demonstrated a continuity in anal-fin ray counts between the two nominal genera, and our more encompassing analysis has found that the anal-fin ray count for Piabina argentea (15-18) is continuous with that for several Creagrutus species (C. barrigai, C. manu, C. para- guayensis), all of which have an upper range of 15 anal-fin NUMBER 613 43 rays. The 15 to 18 anal-fin rays of Piabina urgentea exactly overlaps that of C. pearsoni, a species previously assigned to Piabina (as P. beni), but which our research has shown to be a member of the Creagrutus clade. An analysis of the phyloge- netic relationships within the Creagrutus-Piabina clade shows that the genera constitute sister groups, with Creagrutus diag- nosed by a series of synapomorphic features and with Piabina, in turn, characterized by an autapomorphic modification of the fourth infraorbital. In order to highlight this sister-group rela- tionship between these genera, and to reflect the diagnostic characters for both Creagrutus and Piabina, the genus Piabina is recognized as distinct, contrary to the action of Mahnert and Gery (1988). We herein consider two other nominal genera, Creagrudite Myers (1927) and Creagrutops Schultz (1944), as synonyms of Creagrutus. The type species of Creagrudite, C. maxillaris Myers (1927), is deeply embedded within the phylogeny of Creagrutus, and its continued recognition would render the lat- ter genus nonmonophyletic. Creagrutops was proposed by Schultz (1944) for C. maracaiboensis Schultz (1944), a dimin- utive species endemic to the Lago Maracaibo basin. A single feature, the incomplete poring of the lateral line, was used by Schultz to distinguish Creagrutops from Creagrutus and Crea- grudite. The phylogenetic analysis has shown that this feature is an autapomorphy for the species and that C. maracaiboensis is the sister species to C. nigrostigmatus. The clade formed by these two species shares a series of synapomorphies with the rest of the species of Creagrutus. The continued recognition of Creagrutops as defined by Schultz based on the incomplete poring of the lateral line of C. maracaiboensis would render Creagrutus nonmonophyletic. Such a course of action is unjus- tified, and Creagrutops is placed into the synonymy of Crea- grutus. TYPE SPECIES.—Creagrutus muelleri from Ecuador was originally described by Giinther (1859:92) as Leporinus miil- leri. Soon thereafter (1864:339), Giinther transferred his spe- cies to Creagrutus, designating it at that time as the type spe- cies of the genus. Steindachner (1876:105) subsequently described a second species as Leporinus mulleri based on ma- terial from a number of Amazonian localities. Leporinus mul- leri Steindachner is, however, a member of the characiform family Anostomidae and is not closely related to the species of the same name described by Giinther as the type species of Creagrutus. STATUS OF Creagrutus pellegrini PUYO.—Puyo (1943:143) described Creagrutus pellegrini based on two specimens from the upper Fleuve Itany and Fleuve Maroni of French Guiana. This generic assignment was briefly critiqued by Myers (1960:210) and was followed by Gery (1964:59). Both authors proposed that Puyo's C. pellegrini was a member of the characid genus Chalceus Cuvier. A more in-depth discussion herein is appropriate given the original assignment of the spe- cies to Creagrutus. Notwithstanding the apparent loss of the type series of vari- ous species described by Puyo, presumably including that of Creagrutus pellegrini (Gery, 1959:345-346; Gery and Plan- quette, 1982:68), the information and figures in Puyo's publi- cations (1943, 1949) demonstrate that his assignment of his species to Creagrutus was erroneous. Puyo (1943:144; 1949:129) remarked that the scale row immediately dorsal of the lateral line was formed by "very large scales, the largest of all on the body of this fish" (our translation), a feature obvious in the accompanying illustrations (Puyo, 1943, fig. 2; 1949, fig. 66). Myers noted (1960:211) that such scale-size disparity is limited to Chalceus among New World characiforms (see Eigenmann, 1912, pi. 55: fig. 1, for illustration showing scale- size disparity in Chalceus). We have not discovered such en- larged scales in any Creagrutus or Piabina species, but we have found that feature in all examined Chalceus species. Puyo (1943:143; 1949:129) furthermore noted that Creagru- tus pellegrini has "20 conical teeth, with blunt tips, small and implanted along the external border of the upper jaw" (our translation). The small conical teeth with blunt tips reported for C. pellegrini contrast with the typically tricuspidate teeth on the maxilla and outer portions of the premaxilla in Creagrutus. In addition, the 20 teeth reported along the upper-jaw margin (a count presumably including both premaxillary and maxillary teeth) is higher than in any Creagrutus species. The vast major- ity of Creagrutus species have five or six teeth in the primary premaxillary tooth row and a maximum of five maxillary teeth, total numbers distinctly lower than those reported by Puyo for C. pellegrini. Even Creagrutus maxillaris and C. cracentis, species with highly modified dentition and an increased num- ber of teeth, have three or four teeth in the external row of the premaxilla and 10 to 12 maxillary teeth, which result in totals (13-16) lower than the 20 upper-jaw teeth reported by Puyo for C. pellegrini. Reference to specimens of Chalceus from north- eastern South America, the type region for Creagrutus pelle- grini (USNM 226115), reveal, however, that Puyo's descrip- tion of the form and number of teeth in C. pellegrini corresponds to that of Chalceus specimens from that region. Given this similarity in dentition and the distinctive scale-size disparities common to C. pellegrini and Chalceus, we follow Myers (1960:211) and recognize Creagrutus pellegrini as a doubtful species Chalceus pellegrini (Puyo), and we do not treat it further in this study. DISTRIBUTION.—In our introductory comments we alluded to the broad distribution of the species of Creagrutus and Pia- bina in the regions east of the Andean Cordilleras. This distri- bution has proven to be quite uneven, however, when examined at finer levels (Figure 18). Whereas some gaps in the known distribution of these genera in Cis-Andean South America likely represent the absence of the taxa in certain drainage ba- sins, the absence of these genera, in particular Creagrutus, from various regions is suspect to varying degrees. The absence or rarity of Creagrutus along the main channel of the central and eastern portions of the Amazon River (Figure 44 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY 1 2 29. 10 11 12 15 -17 21 FIGURE 18.—Map of South America showing known occurrence of Creagrutus (dots) and Piabina (stars) species east of the Andean Cordilleras. Many symbols represent more than one lot of specimens and/or collecting local- ity. Drainage basins of note relative to discussion in text (mouth of river basin often indicated) are as follows: 1 = Rio Aroa and Rio Yaracuy, 2=Rio Tuy, 3= Rio Orinoco, 4=Essequibo River, 5=Corantijn River, 6=Maroni or Morawijne River, 7=Fleuve Approuague, 8=Rio Branco, 9=Rio Amazonas, 10=Rio Tapajos, 11 =Rio Xingu, 12=lowerRioTocantins, I3=upperRioTocantins, 14=Rio Jaguaribe, 15=RioSSo Francisco, 16=Rio Araguaia, 17=Rio Paraiba, 18=upper Rio Parana, 19=Rio Uruguay, 20=mouth of Rio de La Plata, 21 = lower Rio Parana, 22=Rio Paraguay, 23=upper Rio Madeira, 24=Rio Ucayali, 25=Rio Huallaga, 26=Rio Maranon, 27=upper Rio Amazonas (Rio Solimoes), 28=Rio Negro, and 29=upper Rio Orinoco. 18, indicated by 9) and lower portions of the main tributary riv- ers likely reflects the absence in such areas of the prime habitat for both Creagrutus and Piabina, namely riffles and rocky bot- toms with moderate to swift water current. Amazonian records for Creagrutus mostly occur peripheral to the central portion of the Amazon basin, typically in uplands where the preferred habitats for most members of the genus are more common. This pattern is particularly apparent in the southeastern, south- western, and western portions of the basin in the Rio Madeira, Rio Ucayali, Rio Huallaga, and Rio Maranon (Figure 18, rivers 23 through 26). Throughout these regions, ichthyological col- lecting activities often yield sympatrically occurring Creagru- tus species, most represented by moderate to sizable population samples. Locality records for Creagrutus from central portions of the Amazon, in contrast, nearly invariably represent single species, typically with smaller numbers of specimens from each site. Similarly, in the adjoining Rio Tocantins system (Figure 18, rivers 12, 13, 16) the majority of population sam- NUMBER 613 45 pies originated in the upriver southern portions of the basin. An examination of the gaps in the known occurrence of Cre- agrutus in Cis-Andean South America within the context of the intensity of ichthyological collecting efforts across that region, raises questions as to the confidence we can place in these gaps as indicative of the actual absence of the genus. In many cases the gaps more likely reflect problems with our overall knowl- edge of the distribution of all components of the Neotropical freshwater fish fauna (see also comments by Bohlke et al., 1978; Vari and Weitzman, 1990; Vari and Reis, 1995). The large gap in the known distribution of the Creagrutus within the relatively poorly sampled Rio Tapajos system (Fig- ure 18, river 10) is notable, with a single sample of C. cracentis from the lower portions of the river and with C ignotus repre- sented by a few samples from two localities in the southern reaches of the basin. More striking is the lack of any Creagru- tus material that originated in the Rio Xingu basin (Figure 18, river 11) and the extremely limited records from the headwater portions of the series of rivers in the region between the Rio Madeira (Figure 18, river 23) and the upper Amazon (Figure 18, river 27). Both the Rio Xingu and these more westerly riv- ers contain numerous headland streams with habitat presum- ably suitable for Creagrutus. We suspect that the absence of samples of the genus from these areas is likely a function of the limited available samples of the ichthyofauna from those ba- sins. Creagrutus is unknown from the various rivers north of the main stream of the Amazon between the mouth of the Rio Ne- gro (Figure 18, river 28) and the mouth of the Amazon (Figure 18, indicated by 9). The only published report of a reasonably thorough ichthyofauna survey within this area is that of Fer- reira (1995) who extensively sampled the lower and middle portions of the Rio Trombetas. Ferreira's survey, although in- cluding sites of swifter-moving water comparable to those in- habited by Creagrutus elsewhere through its range, did not document the presence of the genus within the basin. The re- maining left bank tributaries of the Amazon in this region re- main inadequately surveyed ichthyologically, making a defini- tive statement on the absence of the genus in that region impossible. Even within the Rio Negro basin (Figure 18, river 28), the best sampled left bank tributary to the Amazon, the majority of Creagrutus samples originated in the upper por- tions of the basin. The only record from the Rio Branco (Figure 18, river 8), the major left bank tributary of the Rio Negro is from near the mouth of the Rio Branco into the Rio Negro. Records for Creagrutus in the region between the mouths of the Amazon and Orinoco rivers (Figure 18, rivers 9 and 3, re- spectively) are limited and patchy in distribution. Creagrutus planquettei is apparently endemic to the Fleuve Approuague of eastern French Guiana (Figure 18, river 7). Creagrutus melan- zonus, as defined herein, ranges from eastern Venezuela (Rio Cuyuni basin in the Essequibo River system, Figure 18, river 4) east to the central portions of French Guiana (Figure 18, Fleuve Maroni system, river 6), but with a major gap in the central portion of its known distribution in eastern Guyana and most of Suriname. The species has been reported from the Corantijn River (Figure 18, river 5) along the Suriname-Guiana border (Ouboter and Mol, 1993:146), a report we have been unable to confirm. The only confirmed record for C. melanzonus, or for that matter Creagrutus, from within Suriname is a single record of the species from the Olemari River in the upper reaches of the river basin that forms much of the border between Suri- name and French Guiana (Figure 18, river 6). Ichthyological collecting efforts have been carried out on various Surinamese rivers; however, the habitats appropriate for Creagrutus are of- ten not readily accessible (pers. obs. RPV) through many of the interior portions of that country. This may account for the vir- tual absence of records of the genus within Suriname. Simi- larly, given the limited available samples of the fish fauna from the Brazilian state of Amapa, north of the mouth of the Ama- zon, it is impossible to determine whether the lack of Creagru- tus material from that area is significant. The single species of Piabina, as defined in this study (P. ar- gentea), is totally allopatric to, and complements, the distribu- tion of Creagrutus. Piabina is limited to the eastern portions of South America in the basins of the Rio Sao Francisco (Figure 18, river 15); the Rio Itapicuru, which empties in the Atlantic Ocean about 200 km south of the mouth of the Rio Sao Fran- cisco; the upper Rio Parana (Figure 18, river 18); the Rio Paraiba (Figure 18, river 17); and the Rio Itapemirim, whose mouth is approximately 70 km north of that of the Rio Paraiba. Piabina argentea is the best represented species among those treated in this paper in terms of numbers of samples, reflecting the relatively intensive collecting efforts that have been under- taken within its range, albeit with remaining gaps in its known distribution (Figure 18, stars). The lack of specimens of Pia- bina from the coastal rivers between the Rio Itapicuru and Rio Itapemirim of eastern Brazil and in the areas south of the mouth of the Rio Paraiba (Figure 18, river 17) probably reflects the actual absence of this genus in that region given the exten- sive, although not exhaustive, sampling of the fishes that has been undertaken in that area. Neither Creagrutus nor Piabina are known from the portion of northeastern Brazil east of the Rio Tocantins basin (Figure 18, river 12) and north of the Sao Francisco drainage (Figure 18, river 15). The single possible exception is a Creagrutus specimen (ANSP 164289) in somewhat poor condition, with a stated locality of Russas, on the lower Rio Jaguaribe (Figure 18, river 14), Ceara, Brazil, a site distant from confirmed local- ities for the genus. This record is questionable for several rea- sons. First, Fowler (1941) did not cite Creagrutus, despite commenting (1941:123) that "descriptions also are given of rare or noteworthy specimens." The first record of Creagrutus from northeastern Brazil would have fit the criterion of rare or noteworthy. More notably, the Creagrutus specimen was for- merly part of ANSP 69531-38, the type series of Cheirodon macropterus Fowler (1941:182). Bohlke (1984:50) noted that the type series contained a specimen of Creagrutus, lending credence to the possibility that the Creagrutus specimen was added to the Cheirodon macropterus type series subsequent to 46 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY Fowler's description of the latter species. Even if that is not the case, Roberts (1973:213) suggested that some of the specimens that Fowler (1941) cited as coming from northeastern Brazil originated instead in the Amazon basin; a suggestion supported by subsequent studies. Castro (1990:87) demonstrated that Semaprochilodus squamilentis, a prochilodontid described by Fowler (1941) with a reported type locality in northeastern Brazil, is, rather, endemic to the Rios Tocantins and Xingu of the Amazon basin. Similarly, Vari (1995:80) noted that the Boulengerella cuvieri Agassiz in Spix and Agassiz locality re- ported by Fowler (1941:194) (Rio Parnahya (=Parnaiba), Therezina (=Teresina), Piauhy (=PiauQ) is a considerable range extension that is unconfirmed by other specimens. That species is, however, widespread within the Rio Tocantins basin (Vari, 1995, fig. 45). Definitive identification of the Creagrutus specimen purport- edly from northeastern Brazil is precluded by its condition. Nonetheless, the 39 vertebrae, 12 branched anal-fin rays, over- all head and body form, size and form of the infraorbitals, and residual dark body pigmentation match those of C. seductus, a Rio Tocantins basin endemic. We therefore propose that the specimen originated in the Rio Tocantins basin, as apparently did other specimens reported by Fowler (1941) as having been collected in northeastern Brazil. Creagrutus beni was cited from northwestern Argentina by Pozzi (1945:270) and later by Ringuelet and Aramburu (1961: 30) and Ringuelet et al. (1967:134). Pozzi's reported localities in the provinces of Jujuy and Salta lie some 700 km from the nearest known site for C. beni, and they are within the Rio de La Plata system rather than the upper Rio Madeira basin of the Amazon drainage to which C. beni is endemic. The occurrence of C. beni in the Rio de La Plata basin cannot be confirmed by available specimens, nor were subsequent citations of the spe- cies by later authors based on additional specimens. Indeed, we have been unable to locate any Creagrutus specimens that orig- inated in northwestern Argentina, and recent collecting efforts in that region failed to reveal the presence of the genus (L. Fernandez, pers. comm., 1999). For these reasons, the record of C. beni in northwestern Argentina is considered suspect (see "Remarks" under C. beni). Premaxillary Dentition in Creagrutus and Piabina Premaxillary dentition arrangement has served as the pri- mary criterion both for the recognition of Creagrutus and Pia- bina and for the discrimination of intrageneric species groups within Creagrutus (e.g., Eigenmann, 1927:418; Gery, 1977:406; Gery and Renno, 1989:4). This previous emphasis on the premaxillary dentition of these two genera together with the use of premaxillary tooth patterns in the following keys ne- cessitates a discussion of the system for describing premaxil- lary dentition utilized herein. Divergent identification schemes (see comments by Bohlke (1958) and Howes (1982)) have been applied to characiform dentition patterns, with the arrangement of the premaxillary teeth in Creagrutus and Piabina described within the bauplan of the two rows of premaxillary teeth typical for many charac- ids. That practice, although relatively applicable to two Crea- grutus species (C maxillaris (Figure 4) and C. cracentris) and, to a lesser degree, appropriate for Piabina argentea and five Creagrutus species (C. maracaiboensis, C. melanzonus, C. muelleri, C. peruanus, C. runa), poorly serves as a descriptive framework for the other 57 species of Creagrutus. Previous at- tempts to characterize the dentition of most Creagrutus species in terms of two or more tooth rows resulted in complex de- scriptions of premaxillary tooth patterns (e.g., Eigenmann, 1927:418) that often made it difficult, if not impossible, to vi- sualize the actual tooth pattern and that greatly complicated comparisons of upper-jaw tooth arrangement among species. Our practice (see also Harold and Vari, 1994:4) analyzes the dentition in Piabina argentea and all Creagrutus species, other than C. maxillaris and C. cracentis, in terms of three primary components (see also comments in the phylogenetic discussion of premaxillary dentition concerning potential homologies of different teeth). The first and most generalized pattern within Creagrutus (Figure 2) has a primary row of five or six teeth (seven teeth are sometimes present as an individual variant) that form a shallow arch or sigmoid pattern extending from the anterior portion of the premaxillary symphysis to the postero- lateral region of the premaxilla. The primary premaxillary tooth row demonstrates two major patterns within Creagrutus. Most species have the five to seven sequential teeth of this se- ries either in contact or nearly in contact without a distinctly greater gap between the first and second teeth (the two most medial teeth). A subunit of Creagrutus (C. maracaiboensis, C. melanzonus, C. muelleri, C. nigrostigmatus, C. ouranonastes, C. peruanus, C. runa) and Piabina argentea have a distinct gap between the first and second teeth of that series. The second component to the premaxillary dentition is a tri- angular cluster (triad) of three larger teeth (Figure 3). In the majority of Creagrutus species the anterior tooth of the three tooth cluster is situated distinctly posterior of the arch of the anterior portion of the primary series. Piabina argentea and seven Creagrutus species (C. maracaiboensis, C. melanzonus, C. muelleri, C. nigrostigmatus, C. ouranonastes, C. peruanus, C. runa), in contrast, have a more anterior position of the me- dial cluster of three larger teeth. As a consequence, the anterior tooth of the triangular cluster is partially situated in the gap present between the first and second tooth of the primary series in these species. The final component of the Piabina-Creagrutus premaxillary tooth pattern is a single tooth (Figure 2) situated lateral to the third or fourth tooth of the primary series, or in the region lat- eral to the area of juxtaposition of either the third and fourth or NUMBER 613 47 12 -13 15 FIGURE 19.—Map of South America with heavy lines delimiting regions of Cis-Andean South America repre- sented by different regional "keys" to species of Creagrutus and Piabina. Species common to more than one region are dealt with in the key to each of those regions. Dotted lines delimit subunits of each major Cis-Andean region that serve as basis for citation of species occurrences in Table 3. Neither Creagrutus nor Piabina is known to occur in northeastern Brazil (area east of Rios Tocantins-Araguaia basin, 12 and 13, and north of the Rio Sao Francisco basin, 14) in coastal rivers of eastern Brazil (area east of Rio Sao Francisco basin, 14), in Rio Xingu basin (between areas 6 and 12), or north bank tributary rivers draining into lower portion of Rio Amazonas east of mouth of Rio Negro (area 5). Numbered regions (small capitals) and subregions (when applicable) are as follows: ORINOCO-CARIBBEAN: 1 =Cis-Andean Caribbean versant, 2=lower and middle Rio Orinoco basin, and 3 = upper Rio Orinoco basin, GUI- ANAS: 4=Atlantic coastal drainages of Guyana, Suriname, and French Guiana (=Guyane), no subdivisions, RIO NEGRO: 5=Rio Negro basin, including Rio Branco, no subdivisions. AMAZON: 6=Rio Tapajos, 7=far northwest- ern Amazon basin (Rios Tigre, Napo, Putomayo, Caqueta and intervening basins), 8=far western Amazon basin (Rios Marafion and Huallaga), 9=Westem Amazon basin (Rios Purus, Jurua, southern tributaries to middle Solimoes, and intervening basins). 10=Rio Ucayali, l l=Rio Madeira. TOCANTINS: 12=Rio Araguaia, and 13 = Rio Tocantins. SAO FRANCISCO-PARANA-PARAGUAY: 14=Rio Sao Francisco, 15 = Rio Parana and Rio Paraiba, and 16=Rio Paraguay. Major areas and basins from which Creagrutus or Piabina samples are unknown are not identified on map (see Figure 2 for exact distribution of known localities). 48 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY TABLE 3.—Occurrence of species of Creagrutus and Piabina in major regions and included subregions of Cis- Andean South America discussed in text. See Figure 19 for limits of regions and subregions. Numbered regions (small capitals) and subregions (when applicable) are as follows: ORINOCO-CARIBBEAN: 1 =Cis-Andean Caribbean versant, 2 = lower and middle Rio Orinoco basin, 3=upper Rio Orinoco basin. GU1ANAS: 4=Atlantic coastal drain- ages of Guyana, Suriname, and French Guiana (=Guyane), no subdivisions. RIO NEGRO: 5=Rio Negro basin, including Rio Branco, no subdivisions. AMAZON: 6=Rio Tapajos, 7= far Northwestern Amazon basin (Rios Tigre, Napo, Putomayo, Caqueta, and intervening basins), 8= far Western Amazon basin (Rios Maranon, Huallaga, and Ucayali), 9=Western Amazon basin (Rio Purus indicated by line) and rivers to the north, to the south bank of the main Amazon (Solimoes) and east of the Rio Ucayali, 10=Rio Ucayali of Western Amazon subdivision; and 11 = Southwestern (Rio Madeira (indicated by line) and rivers to south and east of main-stream Amazon below mouth of the Madeira to divide with Rio Tapajos basin. TOCANT1NS: 12=Rio Araguaia, and 13 = Rio Tocantins. SAO FRAN- CISCO-PARANA-PARAGUAY: 13=Rio Sao Francisco and adjoining costal basins, 14=Upper Rio Parana and Rio Paraiba, 15=Rio Parana, and 16=Rio Paraguay (X=present; -=absent). Genus and species Creagrutus amoenus anary atrisignum barrigai beni bolt van calai changae cochui cracentis ephippiatus figueiredoi flavescens gephyrus gracilis gyrospilus holmi hysginus ignotus kunturus lassoi lepidus machadoi magoi manu maxillaris melanzonus melasma menezesi meridionalis molinus mucipu muelleri occidaneus ortegai ouranonastes paraguayensis pearsoni peruanus petilus phasma pila planquettei 1 - - - - - - - - - - X - - - X - - - - - - - - - - - - - - - 2 - - - - - - - - - X X - - X - X - - - - - - - - - - - - - 3 - - - - X - - - - - X - X - - - - - - - - - - - - - - X 4 - - - - - - - - - - - - X - - - - - - - - - - - - - - 5 - - - - X - - - - - - X - - X - - - - - - - - - - X - - 6 - - - - - X - - - - - - - - - - - - - - - - - - Regions and subregions 7 - - X - X - X X X . - - - - - - - - - - - - - - - - 8 X - X - - - X X X X X - - - - X - - - - - - 9 - - X - - - - - _ - - - - - - - X - - - - - - 1 0 X - - - X X - - - - - - - X X - - X X - 1 1 - X X X - - - - - - - X X - - X - - - X . X - 1 2 - - - - - X - - - - X . X - - - - - 1 3 - - X - - X - - X - - - - - _ - X - X - - - - - 1 4 - - - - - - - - - - - - - - 1 5 - - - - - - - - - - - - 1 6 - - - - - - X - X - _ _ NUMBER 613 49 Table 3.—Continued. Genus and species Regions and subregions 1 2 provenzanoi runa saxatilis seductus taphorn i ungulus veruina vexillapinnus xiphos zephyrus Piabina argentea the fourth and fifth tooth of the primary series. This tooth is uniquely absent in Creagrutus molinus among species with this general arrangement of premaxillary teeth. Some authors (e.g., Eigenmann, 1927:418) described the premaxillary tooth pattern present in Piabina argentea and some Creagrutus species (C. maracaiboensis, C. melanzonus, C. muelleri, C. nigrostigmatus, C. ouranonastes, C. peruanus, C. runa) as consisting of two irregular tooth rows, and indeed it can be interpreted in that manner. The premaxillary dentition in these species, however, shares the three components general- ized for most of the species of Creagrutus, and it is this inter- pretation of that arrangement that facilitates the utilization of premaxillary dentition in keys and diagnoses. Creagrutus cracentis and C. maxillari$ have the arrangement of premaxillary teeth highly modified compared with their con- geners, with two rows of teeth clearly present (see Figure 4), a much different situation than in all other members of the genus. Keys to the Species of Creagrutus Giinther and Piabina Reinhardt East of the Andes Although Creagrutus and Piabina can be readily distin- guished internally by a series of differences in a variety of body systems (see "Monophyly of Creagrutus,'" above), they are ex- ternally quite similar. That factor, the speciose nature of Crea- grutus east of the Andean Cordilleras, and the limited range of intrageneric morphological variation compared with the in- trageneric species diversity would make utilizing an all-inclu- sive key to the members of the two genera both difficult and te- dious, particularly for species at the terminus of a long chain of sequential couplets. Most Cis-Andean Creagrutus species have relatively restricted distributions, being typically confined to one of the major regions or drainage basins delimited on Figure 19. It is thus most efficient to present keys for the species known from within each such area. Five Creagrutus species are included in more than one re- gional key. Creagrutus menezesi occurs in both the Amazon and Tocantins basins. Creagrutus maxillaris, C. runa, and C. vexillapinnus occur in both the upper portions of the Rio Orinoco and the Rio Negro systems, the latter a major tributary to the mainstream Amazon. Finally, C zephyrus, although un- known from the Rio Orinoco, does occur in the Rio Casiquiare proximate to where the upper Rio Orinoco bifurcates into the main Rio Orinoco and the Rio Casiquiare of the upper Rio Ne- gro basin. Given such proximity of C. zephyrus to the upper Rio Orinoco, the species is likely present in that drainage sys- tem and is therefore included in the key to the Creagrutus spe- cies of that basin. Table 3 details the known distribution of the species of Crea- grutus in a series of drainage systems in Cis-Andean South America as an aid to determining the composition of the Crea- grutus fauna within a particular region. In some instances the major regions utilized in the keys are subdivided in Table 3 to provide finer-scale distributional information (see descriptions of the major regions and their subregions in legend for Figure 19). Although no single, all inclusive, key for the species of Creagrutus is presented, each species diagnosis details the combination of features that discriminate the species from both Cis- and Trans-Andean congeners. The reader is cautioned that 73% of the Cis-Andean Crea- grutus species recognized herein are first proposed in this study or were described after 1995. Furthermore, many species are known from limited samples, sometimes only from a holotype. Those factors and the patchy ichthyological collecting efforts in many Cis-Andean drainages make it likely that additional Creagrutus species remain undiscovered. Indeed, a significant percentage of the diversity in the genus still may be unknown. Similarly, the distribution of some known forms likely will be extended to varying, perhaps considerable, degrees by future collecting efforts, such as has been the case in other groups of Neotropical fishes, including not only small-sized species but also many medium- and large-sized forms (see examples in Van and Blackledge, 1996; Vari and Reis, 1995; Vari and Or- tega, 1997). 50 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY Key to the Species of Creagrutus in the Amazon Basin Other Than the Rio Negro 1. Premaxilry teeth in 2 distinct rows with outer row consisting of 3 teeth and inner row of 4 teeth on each side [Figure 3]; dentary with 10 to 12 teeth; 5 median scales be- tween posterior margin of anus and anal-fin origin; third infraorbital well developed 2 Premaxillary teeth in 3 series as typical for Creagrutus; usually with 5 or 6, rarely 7 teeth in primary row on each side [Figure 2]; dentary with 4 to 6 teeth; typically 1 or 2, rarely 4, median scales between anus and anal-fin origin, if 4 median scales present between posterior margin of anus and anal-fin origin, then third infraorbital relatively small with posterior and ventral margins falling distinctly short of vertical and horizontal limbs of preopercle 3 2. Postorbital portion of head 36.8%-38.0% of HL; orbital width 37.0%-40.0% of HL; pectoral-fin length 17.9%-20.0% of SL C. cracentis, new species (lower Rio Tapajos basin) Postorbital portion of head 40.6%-^6.8% of HL; orbital width 28.7%-34.6% of HL; pectoral-fin length 15.1%-18.2% of SL C. maxillaris (Rio Orinoco, upper Rio Negro, and upper Rio Madeira basins) 3. Maxilla with 7 to 11 teeth along anteroventral margin; dentary with 10 or 11 teeth C. gephyrus (northwestern Amazon basin) Maxilla with 2 to 5 teeth along anteroventral margin; dentary with 4 to 7 teeth (4 teeth very rare) 4 4. Midlateral surface of body with series of separate dark spots arranged in longitudinal series; spots sometimes coalescing longitudinally, more so on posterior portion of body in larger specimens, particularly those with darker overall pigmentation; pos- terior margin of anus and anal-fin origin separated by 1 median scale 5 Midlateral surface of body lacking series of separate dark spots, or if midlateral pig- mentation present taking form of continuous stripe; posterior margin of anus and anal-fin origin separated by 2 to 4 median scales 6 5. Lateral line scales 35 to 39; vertebrae 36 to 39, rarely 39; depth of caudal peduncle 12.2%-13.8% of SL; distance from dorsal-fin origin to anal-fin origin 33.8%- 38.8% of SL C. amoenus (northwestern Amazon basin) Lateral line scales 39 to 43; vertebrae 38 to 41, typically 39 or 40; depth of caudal pe- duncle 11.1%-12.1% of SL; distance from dorsal-fin origin to anal-fin origin 3O.9%-33.5% of SL C. kunturus (northwestern Amazon basin) 6. Distinct gap present between first and second teeth of primary tooth row of premaxilla on each side, gap partially filled posteriorly by anterior portion of anterior tooth of triangular cluster of posteromedial premaxillary teeth [Figure 1] 7 First and second teeth of primary tooth row of each premaxilla in contact, anterior tooth of triangular cluster of posteromedial premaxillary teeth situated posteromedi- ally of primary row of premaxillary teeth [Figure 2] 9 7. Predorsal scales 13 to 15; dentary teeth 7; scale rows between lateral line and dorsal- fin origin 6; vertebrae 40 to 43 C. ouranonastes, new species (western Amazon basin) Predorsal scales 10 to 13, rarely 13; dentary teeth 5 or 6; scale rows between lateral line and dorsal-fin origin 4 or 5; vertebrae 38 to 40 8 8. Third infraorbital very well developed, wider than diameter of pupil; ventral margin of third infraorbital approaching (smaller specimens) or in contact (larger speci- mens) with horizontal limb of preopercle; posterior margin of third infraorbital ap- NUMBER 613 51 proaching vertical limb of preopercle; anal-fin length 15.3%-17.8% of SL C. muelleri (western Amazon basin) Third infraorbital relatively slender; ventral and posterior margins of third infraorbital distinctly separated from horizontal and vertical limbs of preopercle; posteroventral margin of third infraorbital concentric with rim of orbit; anal-fin length 18.4%- 20.0% of SL C. peruanus (western Amazon basin) 9. Humeral mark horizontally elongate, lying within midlateral stripe C. cochui (western Amazon basin) Humeral mark vertically elongate to varying degrees, extending distinctly above and below midlateral stripe on body when stripe present 10 10. Branched anal-fin rays 13 to 18 11 Branched anal-fin rays 9 to 12 13 11. Distinct midlateral stripe on posterior one-half to two-thirds of body; distance from snout to anal-fin origin 63.5%-66.4% of SL; anal-fin length 20.4%-21.8% of SL C. manu, new species (southwestern Amazon basin) No distinct midlateral stripe on body; distance from snout to anal-fin origin 58.5%-63.4% of SL; anal-fin length 15.6%-20.7% of SL 12 12. Branched anal-fin rays 13 to 15; scale rows between lateral line and dorsal-fin origin 4; distance from snout to dorsal-fin origin 45.4%-49.2% of SL; anal-fin length 18.0%-20.7% of SL; postorbital head length 34.2%-41.9% of HL C. barrigai, new species (northwestern and west central portions of Amazon basin) Branched anal-fin rays 15 to 18 (15 very rare); scale rows between lateral line and dorsal-fin origin 5 or 6; distance from snout to dorsal-fin origin 49.4%-52.9% of SL; anal-fin length 15.6%-17.4% of SL; postorbital head length 41.0%-45.1% of HL C.pearsoni (southwestern Amazon basin) 13. Post-anal median scales to anal-fin origin 4; third infraorbital very narrow, with pos- teromedial margin concentric with margin of orbit C. ungulus, new species (southwestern portions of Amazon basin) Post-anal median scales to anal-fin origin 2; third infraorbital moderately to well de- veloped, when moderately developed posteroventral margin of third infraorbital not concentric with bony margin of orbit 14 14. Basal portions of middle caudal-fin rays with distinct spot of dark pigmentation . . . . C. anary (middle portions of Rio Madeira basin) Basal portions of middle caudal-fin rays without distinct spot of dark pigmentation, sometimes with scattered chromatophores 15 15. Anterior and posterior margins of humeral mark distinct and regular, either nearly vertical or approaching vertical; forming either a vertical bar or a ventrally, gradual- ly attenuating, vertically elongate triangle 16 Shape of humeral mark variable, sometimes with margins quite defuse (C. ho/mi); overall form of mark rotund, anteriorly concave, or somewhat rhomboidal . . . . 19 16. Gill rakers on lower limb of first gill arch 11 to 13, scales above lateral line to dorsal- fin origin 3 or 4; bony orbital diameter 32.6%-37.9% of HL; lateral line scales 36 to 38; anal-fin length 15.9%-19.5% of SL; anteroventral portion of third infraorbital approaching or contacting horizontal limb of preopercle C. occidaneus, new species (western portions of Amazon basin) 52 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY Gill rakers on lower limb of first gill arch 8 to 10; scales above lateral line to dorsal- fin origin 4 to 6; if 4 then bony orbital diameter 29.5%-32.7% of HL (C. beni) or lateral line scales 38 to 43; anal-fin length 19.3%-22.7% of SL; and anteroventral portion of third infraorbital falling distinctly short of horizontal limb of third in- fraorbital (C. pila) 17 17. Lateral line scales 35 to 37; scale rows between lateral line and anal-fin origin 3; teeth on each dentary 5; distance from snout to pectoral-fin insertion 25.7%-28.5% of SL; pelvic-fin length 16.4%-19.6% of SL; anal-fin length 19.3%-22.7% of SL . . . C. pila, new species (western portions of Amazon basin) Lateral line scales 38 to 43, 38 uncommon; scale rows between lateral line and anal- fin origin 3 or 4; if 38 lateral line scales or 3 scale rows between lateral line and anal-fin origin present, then 6 teeth present on each dentary; distance from snout to pectoral-fin insertion 21.2%-26.0% of SL; pelvic-fin length 13.9%-16.8% of SL; anal-fin length 19.3%-22.7% of SL 18 18. Width of orbit 8.7%-10.3% of SL; width of orbit equals or exceeds horizontal dis- tance from posterior margin of orbit to posterior margin of opercle; 5 teeth present on each dentary C. changae, new species (western portions of Amazon basin) Width of orbit 7.1%—8.4% of SL; width of orbit less than horizontal distance from posterior margin of orbit to posterior margin of opercle; 6 teeth present on each den- tary C. beni (southwestern portions of Amazon basin) 19. Humeral mark rhomboidal [Figure 71] C. ortegai, new species (western portions of Amazon basin) Humeral mark diffuse, rounded, or anteriorly concave 20 20. Ventral margin of third infraorbital in adults contacting horizontal limb of preopercle 21 Ventral margin of third infraorbital in adults not contacting horizontal limb of preo- percle 23 21. Humeral mark diffuse and distinctly wider dorsally [Figure 46] C. holmi, new species (western portions of Amazon basin) Humeral mark distinct and anteriorly curved 22 22. Distance from dorsal-fin origin to hypural joint 53.3%-55.4% of SL; distance from dorsal-fin origin to anal-fin origin 26.9%-30.5% of SL; distance from dorsal-fin or- igin to pelvic-fin insertion 21.5%-25.4% of SL; distance from dorsal-fin origin to pectoral-fin insertion 28.5%-30.7% of SL; caudal peduncle depth 9.3%-10.7% of SL C. ignotus, new species (Rio Tapajos basin) Distance from dorsal-fin origin to hypural joint 55.5%—61.9% of SL; distance from dorsal-fin origin to anal-fin origin 32.4%-40.4% of SL; distance from dorsal-fin or- igin to pelvic-fin insertion 30.2%—35.1% of SL; distance from dorsal-fin origin to pectoral-fin insertion 32.0%-36.6% of SL; caudal peduncle depth 11.5%-13.7% of SL C. flavescens, new species (western portions of Amazon basin) 23. Primary tooth row of premaxilla with 5 teeth; 8 to 10 gill rakers on upper and 11 to 13 gill rakers on lower limb of first gill arch; 39 to 43 lateral line scales C. gracilis, new species (western portions of Amazon basin) Primary tooth row on premaxilla with 6 teeth; 5 or 6 gill rakers on upper and 9 to 11 gill rakers on lower limb of first gill arch; 36 to 39 lateral line scales C. petilus, new species (southwestern portions of Amazon basin) NUMBER 613 53 Key to the Species of Creagrutus in the Rio Negro Basin 1. Premaxillary teeth in 2 distinct rows [Figure 4]; outer row consisting of 3 teeth and in- ner row of 4 teeth; maxilla elongate, with 10 to 12 tricuspidate teeth along an- teroventral margin; each dentary with 10 to 12 teeth; 5 scales between posterior margin of anus and anal-fin origin C. maxillaris (Rio Orinoco, upper Rio Negro, and upper Rio Madeira basins) Premaxillary teeth in 3 series typical for Creagrutus species, with 4 to 7 teeth in prima- ry row of each side [Figure 2]; maxilla of moderate length, with 2 or 3 tricuspidate teeth along margin; each dentary with 4 to 6 teeth; 2 scales between posterior mar- gin of anus and anal-fin origin 2 2. Branched anal-fin rays 12 to 14; dorsal fin with distinct patch of black pigmentation on middle portion of last unbranched and first six branched rays C. vexillapinnus, new species (middle and upper Rio Negro and upper Rio Orinoco basins) Branched anal-fin rays 9 to 11; dorsal fin lacking distinct patch of black pigmentation on middle portion of last unbranched and first six branched rays 3 3. Primary series of premaxillary dentition consisting of 4 teeth C. runa, new species (upper Rio Negro and upper Rio Orinoco basins) Primary series of premaxillary dentition with 5 to 7 teeth 4 4. Basal portions of middle caudal-fin rays without dark pigmentation C. menezesi, new species (Rio Negro basin and Rio Tocantins basin) Basal portions of middle caudal-fin rays with dark pigmentation 5 5. Primary series of premaxillary teeth with 5 teeth; humeral mark in form a distinctly ar- cuate stripe; dark pigmentation on caudal fin horizontally elongate mark on mid- portion of middle caudal-fin rays C. phasma (upper portion of Rio Negro, Rio Orinoco basin) Primary series of premaxillary teeth with 6, rarely 5 teeth; humeral mark vertically elongate, but not distinctly arched; caudal-fin pigmentation, when present, either a rounded spot on basal portions of middle caudal-fin rays or extending along length of middle caudal-fin rays 6 6. Postorbital head length 43.7%^7.4% of HL; bony orbital diameter 31.3%-35.7% of HL; predorsal scales 10 to 12; caudal pigmentation, when present, extending along length of middle caudal-fin rays C. ephippiatus, new species (Rio Siapa, upper Rio Negro basin) Postorbital head length 35.1%-41.0% of HL; bony orbital diameter 36.9%-40.3% of HL; predorsal scales 8 or 9; caudal pigmentation, when present, a rounded spot on basal portions of middle caudal-fin rays C. zephyrus, new species (upper Rio Negro and Rio Casiquiare) Key to the Species of Creagrutus in the Rio Tocantins Basin 1. Premaxillary lacking single tooth typically lying lateral to fourth or fifth tooth of pri- mary series in most Creagrutus species; distance from dorsal-fin origin to pelvic-fin insertion 21.5% of SL; distance from dorsal-fin origin to pectoral-fin insertion 27.8% of SL C. molinus, new species (upper Rio Araguaia basin) 54 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY Premaxillary with single tooth typically lying lateral to fourth or fifth tooth of primary series [Figures 1-3]; distance from dorsal-fin origin to pelvic-fin insertion 28.2%-35.0% of SL; distance from dorsal-fin origin to pectoral-fin insertion 29.6%-35.8% of SL 2 2. Scale rows between dorsal-fin origin and lateral line 5 3 Scale rows between dorsal-fin origin and lateral line 4 4 3. Humeral mark dark, horizontally elongate in larger specimens; secondary pigmented region located slightly dorsal of primary humeral mark, sometimes joined to it by vertical patch of less densely concentrated melanophores; gill rakers on upper por- tion of first arch 7 or 8, usually 8 C. atrisignum (upper Rio Tocantins basin) Humeral mark moderately pigmented, rotund or vertically elongate (more so in larger individuals); without distinct secondarily pigmented region slightly dorsal of prima- ry humeral mark; when humeral mark vertically elongate, intensity of pigmentation fading dorsally; gill rakers on upper portion of first arch 6 or 7, most often 6 C. britskii, new species (upper Rio Tocantins basin) 4. Branched anal-fin rays 9 or 10 5 Branched anal-fin rays 11 to 13 6 5. Premaxilla with 5 teeth in primary series; humeral mark approximating form of in- verted comma [Figure 40] with distinctly anteriorly concave margin; region of mark immediately dorsal of lateral line distinctly darker than remaining portions of mark C. figueiredoi, new species (upper Rio Tocantins andupper Rio Araguaia basins) Premaxilla with 6, rarely 7, teeth in primary series; humeral mark vertically elongate and ventrally tapering, with anterior margin straight or barely concave; intensity of pigmentation not varying along length of mark C. menezesi, new species (upper Rio Araguaia basin, Rio Tocantins, Rio Negro) 6. Body with series of dark chevron-shaped marks on midlateral surface in larger speci- mens [Figure 68], with dorsal branch of chevron more pronounced in medium-sized individuals; distal margin of caudal fin with dusky band separated by hyaline region from basal dusky portion of fin; 5 teeth in primary premaxillary tooth series; gill rakers 6-7 + 9-11 C. mucipu, new species (upper Rio Tocantins basin) Body lacking series of dark chevron-shaped marks on midlateral surface; caudal pig- mentation lacking distinct distal band; 6 or 7, rarely 5 teeth in primary premaxillary tooth series (5 teeth rarely present in C. saxatilis, which has 8-10+ 13-14 gill rak- ers) 7 7. Lateral line scales 37 to 39; vertebrae modally 37, rarely 36 or 38; interorbital distance 31.6%-36.4% of HL; depth of caudal peduncle 11.3%-12.2% of SL; gill rakers on upper limb of first arch 8 to 10, rarely 8; gill rakers on lower limb of first arch 11 to 13, rarely 13 C. saxatilis, new species (upper Rio Tocantins basin) Lateral line scales 39 to 41; vertebrae 38 or 39; interorbital distance 28.4%-31.9% of HL; depth of caudal peduncle 10.6%-11.2% of SL; gill rakers on upper limb of first arch 7 or 8; gill rakers on lower limb of first arch 13 or 14 C. seductus, new species (upper Rio Araguaia basin) Key to the Species of Creagrutus in the Guianas, including the Rio Cuyuni Primary tooth row of premaxilla usually with 5 teeth; body shallow and fusiform; dentary teeth 6 or 7; humeral mark a short vertical crescent with slight anterior concavity; lat- NUMBER 613 55 eral line scales 35 to 38; gill rakers on lower limb of first gill arch 10 to 12; orbital di- ameter 34.8%-42.9% of HL; 35 to 37 vertebrae C. melanzonus (Essequibo River drainage, Guyana and eastern Venezuela to Fleuve Sinnamary, central French Guiana) Primary tooth row of premaxilla usually with 6 teeth; body deep and laterally compressed; dentary teeth 5; humeral mark ovate, horizontally elongate; lateral line scales 38 to 40; gill rakers on lower limb of first gill arch 12 to 13; orbital diameter 29.2%-36.7% of HL; 38 or 39 vertebrae C. planquettei (Fleuve Approuague, eastern French Guiana) Key to the Species of Creagrutus in the Rio Orinoco Basin and Cis-Andean Caribbean Versant Drainages 1. Premaxillary dentition in 2 distinct rows [Figure 4]; outer tooth row consisting of 3 teeth and inner row of 4 teeth; maxilla elongate, with 10 to 12 teeth along an- teroventral margin; each dentary with 10 to 12 teeth C. maxillaris (Rio Orinoco, upper Rio Negro, and upper Rio Madeira basins) Premaxillary dentition with 3 components typical for Creagrutus species, with 4 to 6 teeth in primary row of each premaxilla [Figure 2]; maxilla of moderate length, with 2 to 7 teeth along margin; each dentary with 5 to 8 teeth 2 2. Primary row of premaxillary teeth with 6 teeth 3 Primary row of premaxillary teeth with 4 or 5, usually 5, teeth 15 3. Humeral mark in the form of a circular blotch 4 Humeral mark in the form of a vertical bar of various shapes 5 4. Third infraorbital well developed, its ventral margin approaching or contacting hori- zontal limb of preopercle; 4, occasionally 5, horizontal scale rows between lateral line and dorsal-fin origin; bony orbital diameter 25.8%-31.7% of HL; maxillary teeth usually 3 or 4, rarely 2 C. gyrospilus, new species (upper portions of northern tributaries of Rio Apure) Third infraorbital relatively small with a broad gap separating its ventral margin from horizontal limb of preopercle; 5 horizontal scale rows between lateral line and dor- sal-fin origin; bony orbital diameter 28.5%-36.1% of HL; maxillary teeth usually 4 or 5 C. hysginus (rivers draining into Golfo de Paria, northeastern Venezuela) 5. Humeral mark not very wide, in the form of a narrow, vertical to anteriorly concave bar; horizontal scale rows between lateral line and anal-fin origin 2 or 3; anal-fin ray hooks, when present, on first branched ray only; postorbital head length 35.1%- 41.0% of HL 6 Humeral mark well developed, in the form of a broad, vertical to anterodorsally ta- pered bar with maximum width immediately dorsal of lateral line; horizontal scale rows between lateral line and anal-fin origin 3 to 5; anal-fin ray hooks, when present, on first 2 to 5 branched rays; postorbital head length 38.4%-53.5% of HL 7 6. Small, diffuse spot of dark pigmentation on anterior portion of middle caudal-fin rays; caudal peduncle depth 9.7%-10.9% of SL; 2 or 3, usually 3, horizontal scale rows between lateral line and dorsal-fin origin; vertebrae 38 or 39 C. zephyrus, new species (upper Rio Negro and Rio Casiquiare drainages) No spot of dark pigmentation on anterior portion of middle caudal-fin rays; caudal pe- duncle depth 10.8%-l 1.7% of SL; 4 horizontal scale rows between lateral line and dorsal-fin origin; vertebrae 36 or 37 C. xiphos, new species (Rio Mato, Rio Caura basin) 56 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY 7. Body somewhat tubular; branched anal-fin rays 9 to 13; interorbital distance 34.0%- 37.9% of HL C. atratus, new species (upper Rio Meta) Body slightly compressed, not tubular; branched anal-fin rays 8 to 12; interorbital dis- tance 26.1%-35.4% of HL 8 8. Third infraorbital bone well developed, its ventral margin approaching or contacting horizontal limb of preopercle; humeral mark distinctly expanded anteriorly and pos- teriorly directly dorsal of lateral line, tapered and/or curved anterodorsally behind head 9 Third infraorbital bone small, with a broad gap separating its ventral margin from hor- izontal limb of preopercle; humeral mark a uniform vertical bar or a bar with a slight expansion dorsal of lateral line 11 9. Gill rakers on upper portion of first gill arch 9 to 11; gill rakers on lower portion of first gill arch 13 or 14; interorbital distance 30.2%-34.3% of HL; lower lip not pig- mented C. magoi, new species (Rio Chaviripa) Gill rakers on upper portion of first gill arch 7 to 9; gill rakers on lower portion of first gill arch 11 to 13; interorbital distance 27.4%-32.0% of HL; lower lip pigmented . 10 10. Elongate dark pigment spot along middorsal portion of body immediately posterior of head; dentary teeth 6 or 7; humeral mark attenuated ventrally, appearing overall as an inverted comma; bony orbital diameter 33.2%-39.0% of HL; caudal peduncle depth 9.9%-11.3% of SL; pectoral-fin rays 12 to 14; dentary teeth 6 or 7 C. provenzanoi, new species (Rio Cataniapo) No dark elongate dark pigment spot along middorsal portion of body posterior of head; dentary teeth 5; humeral mark not attenuated ventrally, appearing as a cen- trally expanded vertical bar; bony orbital diameter 31.1 %-35.6% of HL; caudal pe- duncle depth 10.4%-12.2% of SL; pectoral-fin rays 13 to 15; dentary teeth 5 C. calai, new species (upper Rio Meta) 11. Branched anal-fin rays 8 to 10; maxillary teeth 2 to 4; anal-fin ray hooks, when present, on first 1 or 2 branched rays; interorbital distance 26.1%-33.3% of HL; snout to dorsal-fin origin 45.0%-50.9% of SL; predorsal median scales 8 to 10 . . . 12 Branched anal-fin rays 10 to 12; maxillary teeth 2 to 5; anal-fin ray hooks, when present, on first 2 to 4 branched rays; interorbital distance 28.6%-35.4% of HL; snout to dorsal-fin origin 47.5%-53.6% of SL; predorsal median scales 8 to 13 . 13 12. Bony orbital diameter 33.5%-43.O% of HL; interorbital distance 26.1%-30.0% of HL; postorbital head length 38.4%-43.8% of HL; caudal-peduncle depth 9.9%- 11.2% of SL C. machadoi, new species (upper Rio Caura) Bony orbital diameter 28.2%-36.6% of HL; interorbital distance 28.0%-33.3% of HL; postorbital head length 41.4%^*9.5% of HL; caudal peduncle depth 10.9%- 13.2% of SL C. bolivari (lower tributaries and near main channel of Rio Orinoco to upper Rio Meta) 13. Dorsal-fin origin at, or slightly posterior of, vertical through pelvic-fin insertion; dark, narrow median line of pigmentation on predorsal surface of body, pigmentation of- ten restricted to anterior one-half of that region; pectoral-fin rays 11 or 12; interor- bital distance 29.3%-33.5% of HL; postorbital head length 46.7%-53.5% of HL; snout to pelvic-fin insertion 41.9%-51.1% of SL; snout to dorsal-fin origin 47.5%- 53.6% of SL C. lassoi, new species (Rios Aroa and Yaracuy, Caribbean versant of northern Venezuela) NUMBER 613 57 Dorsal-fin origin at, or slightly anterior of, vertical through pelvic-fin insertion; no median line of dark pigmentation on predorsal surface; pectoral-fin rays 11 to 13; interorbital distance 28.6%-35.4% of HL; postorbital head length 45.1%-51.9% of HL; snout to pelvic 44.2%-49.0% of SL; snout to dorsal-fin origin 47.8%-51.7% of SL 14 14. Humeral mark even vertical bar; gap between infraorbitals 4 through 6 and vertical limb of preopercle approximately constant in width; posterior margins of many scales on flank undulate to crenate; lower jaw and lip unpigmented; pelvic-fin ray hooks, when present, on both medial and lateral surfaces of branched rays, most highly developed on medial 2 or 3 rays; predorsal median scales 8 to 11; lateral line scales 37 to 39; gill rakers on upper limb of first gill arch 5 to 7 C. crenatus, new species (Caribbean versant drainages of Estado Lara, northern Venezuela) Humeral mark a vertical bar, somewhat expanded anteriorly and posteriorly immedi- ately dorsally of lateral line; gap between infraorbitals 4 through 6 and vertical limb of preopercle decreasing in width dorsally; posterior margins of many scales on flank smooth to slightly undulate; lower jaw, dorsally, and lip, pigmented; pelvic- fin ray hooks, when present, on medial surfaces of branched rays only; predorsal median scales 9 to 13; lateral line scales 36 to 38; gill rakers on upper limb of first gill arch 6 to 8 C. taphorni, new species (Rio Orinoco basin, north central Venezuela, and Rio Tuy of Caribbean versant of northern Venezuela) 15. Scale rows between lateral line and dorsal-fin origin 5 or 6; scale rows between lateral line and anal-fin origin 4 or 5; lateral line scales 34 to 37; humeral mark either ob- scured by lateral stripe or a straight, vertical to slightly oblique, bar angled from an- teroventral to posterodorsal; body transversely compressed 16 Scale rows between lateral line and dorsal-fin origin 4; scale rows between lateral line and anal-fin origin 2 or 3, rarely 4; lateral line scales 38 to 43; humeral mark a short vertical bar or an anteriorly concave shallow crescent; body shallow and fusiform 17 16. Humeral mark absent; solid, dark lateral stripe along entire length of body, obscuring humeral mark; hooks on anal-fin rays, when present, on up to first 10 branched rays; lateral line scales 36 or 37; gill rakers on upper limb of first gill arch 6 or 7 C. lepidus (Rios Aroa and Urama, Caribbean versant of northern Venezuela) Humeral mark present, a straight, vertical to slightly oblique, bar angled from an- teroventral to posterodorsal; lateral stripe anteriorly diffuse, as in most Creagrutus species, extending from slightly posterior of humeral mark to base of caudal fin; hooks on anal-fin rays, when present, on up to first 3 to 5 branched rays; lateral line scales 34 to 36; gill rakers on upper portion of first gill arch 3 to 6 . . . C. melasma (upland tributaries of northern portion of Rio Orinoco, and Rios Tuy and Neveri of Caribbean versant of northern Venezuela) 17. Branched anal-fin rays 11; horizontal scale rows between anal-fin origin and lateral line 2; central caudal-fin rays diffusely pigmented, with no obvious spot or stripe; maxillary teeth 3 or 4 C. veruina, new species (Rio Cataniapo) Branched anal-fin rays 9 or 10; horizontal scale rows between anal-fin origin and lat- eral line 2 to 4, usually 3; central caudal-fin rays with distinct dark stripe restricted to anterior one-half of fin; maxillary teeth 4 to 7 C. phasma (upper Rio Orinoco and Rio Casiquiare drainages) 58 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY Key to the Species of Creagrutus and Piabina in the Rio de La Plata and Rio Sao Francisco Basins and Rivers of Southeastern Brazil 1. First and second teeth of primary premaxillary tooth row separated by distinct gap [Figure 1]; dorsal-fin origin to hypural joint 48.5%-52.7% of SL; caudal-peduncle depth 9.0%-10.9% of SL; branched anal-fin rays 15 to 18 Piabina argentea (Rio Sao Francisco, Rio Itapicuru, upper Rio Parana, Rio Paraiba and Rio Itapemirim basins) First and second teeth of primary premaxillary tooth row in contact along their adjoin- ing margins [Figure 2]; dorsal-fin origin to hypural joint 52.5%-59.8% of SL; cau- dal-peduncle depth 10.5%-12.5% of SL; branched anal-fin rays 11 to 15 2 2. Snout to anal-fin origin 62. l%-66.4% of SL; scale rows between lateral line and dor- sal-fin origin 4; branched anal-fin rays 11 to 13 Creagrutus meridionalis, new species (middle and upper portions of Rio Paraguay basin) Snout to anal-fin origin 55.3%-61.0% of SL; scale rows between lateral line and dor- sal-fin origin 5; branched anal-fin rays 13 to 15 Creagrutus paraguayensis (middle portions of Rio Paraguay basin) Species Accounts To facilitate the location of, and cross reference between, ac- counts for the different species, the species descriptions are ar- ranged alphabetically within Creagrutus regardless of their re- gion^) of occurrence. These are followed by the description of Piabina argentea. Creagrutus amoenus Fowler, 1943 FIGURES 20-22, TABLE 4 Creagrutus amoenus Fowler, 1943a:239, fig. 18 [type locality: Colombia (Caqueta), Florencia, Rio Ortuguasa (=Orteguaza); one paratype=C. _/fave- scens]; 1948:82, fig. 86 [literature record based on Fowler, 1943a]; 1975:25 [literature compilation].—Gery, 1977:407 [in key].—Wilkens, 1977:156 [paratype despository].—Bohlke, 1984:42 [type depository].—Castro and Arboleda, 1988:8 [Colombia, Rio Caqueta].—Van et al., 1995:289 [compari- sons with C. kunturus; C. boehlkei Gery (1972) tentatively placed as syn- onym of C. amoenus Fowler].—Roman-Valencia and Cala, 1996:145 [dis- cussion of species based on literature information]. Creagrutus mulleri [not of Gunther, 1859].—Bohlke, 1958:30, tab. 3, pi. 3: fig. 1 [misidentification] [Ecuador (Napo), Rio Tutapischo, Rio Villano, headwa- ters of Rio Arajuno]. Creagrutus boehlkei Gery, 1972:63, tab. 5, pi. iv: fig. 2 [type locality: Ecuador, "Oriente del Ecuador" (eastern portion of Ecuador); also Rio Conambo, Rio Capotazo, Rio Villano]; 1977:407 [in key].—Wilkens, 1977:156 [paratype depository].—Stewart et al., 1987:26 [Ecuador, Rio Napo].—Ibarra and Stewart, 1989:369 [Ecuador, upper Rio Napo basin].—Barriga, 1991:17 [lit- erature compilation; eastern portion of Ecuador; based on Gery, 1972].—Van et al., 1995:289 [C. boehlkei tentatively placed as synonym of C. amoenus]. [New synonymy.] Creagrutus muelleri [not of Gunther, 1859].—Saul, 1975:106 [misidentifica- tion] [Ecuador: Napo (now in Sucumbios), Santa Cecilia, Rio Conejo; ecolo- gy and stomach contents]. DIAGNOSIS.—The combination of the possession of premax- illary dentition arranged in the three components generalized for most of the species of Creagrutus and Piabina without a pronounced gap between the first and second teeth of the pri- mary premaxillary tooth series, 2 to 4 maxillary teeth, the typi- cal possession of 6 teeth in the primary premaxillary tooth se- ries, 1 post-anal medial scale to the anal-fin origin, 4 scale rows between the lateral line and the dorsal-fin origin, the pigmenta- tion pattern of a series of dark spots along the midlateral line on the body that ontogenetically coalesce, sometimes resulting in a solid stripe in larger individuals, the lack of a distinct patch of pigmentation on the middle portions of the dorsal fin, and the absence of a distinct, vertically elongate humeral mark distin- guishes C. amoenus from all congeners with the exception of C. kunturus. Creagrutus amoenus can be separated from C. kunturus, the only other member of the genus with comparable pigmentation on the body and one post-anal scale, by the com- bination of the number of lateral line scales (35-39 in C. amoe- nus versus 39-43 in C. kunturus), total vertebrae (36-39, rarely 39, in C. amoenus versus 38-41, typically 39-40, in C. kuntu- rus), the depth of the caudalpeduncle (12.2%-13.8% of SL in C. amoenus versus 11.1 %—12.1% of SL in C. kunturus), and the distance from the dorsal-fin origin to the anal-fin origin (33.8%- 38.8% of SL in C. amoenus versus 30.9%-33.5% of SL in C. kunturus). DESCRIPTION.—Morphometric and meristic data for C. amoenus in Table 4. Head and body relatively robust. Greatest body depth at dorsal-fin origin in smaller individuals, variably at, or somewhat anterior of, that line in larger individuals. Dor- sal profile of head from tip of snout to rear of supraoccipital spine, ranging from smooth and slightly convex in some speci- mens to distinctly convex with irregular profile above nostrils in other individuals. Interorbital region distinctly convex. Pre- dorsal profile of body with variably evident change in align- ment relative to that of head; slightly convex in smaller speci- mens, typically distinctly so in larger individuals. Dorsal NUMBER 613 59 TABLE 4.—Morphometrics and meristics of Creagrutu.i amoenus: (A) holotype of C. amoenus, ANSP 70499; (B) holotype of C. boehlkei, ZSM 28428; and (C) all other specimens of C. amoenus from which counts and measure- ments were taken (n=59). Standard length is expressed in mm; measurements 1 to 14=percentages of standard length; 15 to 18=percentages of head length. Characters Standard length 1. Snout to anal-fin origin 2. Snout to pelvic-fin insertion 3. Snout to pectoral-fin insertion 4. Snout to dorsal-fin origin 5. Dorsal-fin origin to hypural joint 6. Dorsal-fin origin to anal-fin origin 7. Dorsal-fin origin to pelvic-fin insertion 8. Dorsal-fin origin to pectoral-fin insertion 9. Caudal peduncle depth 10 Pectoral-fin length 11. Pelvic-fin length 12. Dorsal-fin length 13. Anal-fin length 14. Head length 15. Postorbital head length 16. Snout length 17. Bony orbital diameter 18. Interorbital width Lateral line scales Scale rows between dorsal-fin origin and lateral line Scale rows between anal-fin origin and lateral line Predorsal median scales Branched dorsal-fin rays Branched anal-fin rays Branched pelvic-fin rays Pectoral-fin rays Vertebrae A 66.5 68.6 49.5 26.6 48.7 55.3 34.0 29.9 33.1 12.8 22.3 16.5 23.8 17.3 26.9 43.6 24.8 29.6 29.6 37 4 3 9 8 11 7 11 37 B Morphometrics 91.2 66.2 49.5 27.8 48.3 55.1 36.7 32.9 35.5 13.0 21.2 16.8 21.5 17.4 28.0 48.2 27.8 29.4 29.4 Meristics 37 4 3 10 8 11 7 11 37 C 35.4-91.2 62.6-70.8 45.9-50.2 23.7-29.5 47.1-51.7 53.5-58.8 33.8-38.8 29.0-35.6 32.8-38.4 12.2-13.8 19.5-22.9 15.6-18.9 20.1-24.5 16.0-22.3 25.3-29.9 41.7^9.3 24.4-32.1 29.3-34.0 25.7-33.0 35-39 4 3 9-10 7-8 10-12' 6-72 10-14 36-393 'Eleven branched dorsal-fin rays typical, 10 or 12 rays present in fewer than 5% of examined specimens. 2Seven branched pelvic-fin rays typical. 3Thirty-nine vertebrae present in only one examined paratype. profile of body inclined at dorsal-fin base, ranging from nearly straight between posterior insertion of dorsal fin and caudal pe- duncle to slightly convex in region of adipose fin. Ventral pro- file of head with variably obtuse angle at anteroventral corner of dentary, gently curved from that region to isthmus. Ventral profile of body convex to anal-fin origin, convexity more pro- nounced in deep-bodied individuals. Head obtusely pointed in lateral view, distinctly pointed in dorsal view. Upper jaw distinctly longer than, and overhanging, lower jaw. Anterior portion of snout fleshy, with scattered papil- lae. Papillae more concentrated along ventral margin of upper lip and on fleshy folds and plicae extending between outer and medial premaxillary teeth and along dorsal margin of lower lip. Infraorbital series moderately developed, proportionally more extensive posteriorly in larger specimens. Ventral margin of third infraorbital curved, deepest region of infraorbital con- tacting, or nearly contacting, horizontal limb of preopercle. Posterior margins of third through fifth infraorbitals distinctly separated from vertical limb of preopercle. Premaxillary dentition in three series: primary row slightly curved or sigmoid, typically with 6 teeth (5 teeth present on one side of head in one specimen) without pronounced gap between first and second tooth of series and with medial tooth separated from its equivalent tooth of contralateral series by distinct gap; triangular cluster of 3 larger teeth; and single tooth of form sim- ilar to that of primary series occurring lateral to fourth tooth of primary premaxillary row (2 teeth present in this region of one premaxilla in one, apparently anomalous, specimen). Maxilla with 2 to 4 teeth; teeth all tricuspidate when 2 or 3 teeth present, fourth tooth often with irregular, but not distinctly tricuspidate, distal margin. Dentary typically with 6 teeth, 5 teeth present on dentary on one side of jaws in several specimens. Three anterior dentary teeth distinctly larger than remaining teeth and tricuspi- date, with central cusp largest; second tooth largest, about twice as large as first tooth and three times as large as third tooth. Three posterior dentary teeth gradually becoming smaller, with approximately equal and distinct cusps (teeth 4 and 5) or barely apparent cusps (tooth 6, when present). 60 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY FIGURE 20.—Creagrutus amoenus, ANSP 145981, 81.0 mm SL; Ecuador, Napo, tributary to Rio Napo, approximately 15 mi (23 km) downstream of Missahuali (0°56'N, 77°30'W). FIGURE 21.—Creagrutus amoenus, MEPN 4626, 76.0 mm SL; Ecuador, Napo, Rio Cowi (0°08'10"S, 76°15'18"W). Dorsal-fin rays typically ii,8, rarely ii,7. Dorsal-fin origin ap- proximately at vertical through pelvic-fin insertion. Profile of distal margin of dorsal fin straight to very slightly concave. Anal-fin rays ii-iii,10-12. Profile of distal margin of anal fin straight to slightly concave. Hooks typically present on anal-fin rays in mature males of many Creagrutus species not present in examined specimens. Pectoral-fin rays i,9—13; relative length of fin somewhat variable, tip extending posteriorly into area slightly to distinctly short of vertical through pelvic-fin inser- tion. Pelvic-fin rays i,6,i in some small specimens, i,7 in major- ity of examined individuals. Tip of pelvic fin falling slightly to distinctly short of anus. Hooks typically present on pelvic-fin rays in mature males of many Creagrutus species not present in examined specimens. Gill rakers of first arch relatively short on epibranchial, elon- gate on ceratobranchial; 7-8 + 9-11. COLORATION IN LIFE (based on a transparency of an aquar- ium specimen provided by H.-G. Evers and the examination of recently collected specimens still in formalin at MEPN).— Overall coloration silvery, more so midlaterally and ventrally. Region above midlateral line with pronounced yellow tint. Yel- low coloration most concentrated immediately above midlat- eral silvery stripe that overlies darker midlateral stripe seen in preserved specimens lacking guanine. Dorsal surface of head yellow. Dorsal fin yellowish, with yellow pigmentation most concentrated along most of length of anterior rays and central portions of remaining rays. Caudal-fin lobes yellow, more so basally, with distal portions having only faint yellow pigmenta- tion. Anal fin with patch of intense yellow pigmentation over- lying central portions of all rays, pigmentation more intense an- NUMBER 613 61 FIGURE 22.—Map of central and northern South America showing geographic distribution of Creagrutus amoe- nus (dots, 1 =type locality), Creagrutus anary (squares, 2=type locality based on information in original species description; 3=type locality according to Bohlke, 1955), Creagrutus atratus (star, 4=type locality), and Creagru- tus atrisignum (triangles, 5=type locality) (some symbols represent more than one locality or lot of specimens). teriorly. Pelvic fin with intense yellow pigmentation on central portions of all but lateralmost rays. Lateralmost pelvic-fin rays with distinct white coloration in photographs of live aquarium specimen. Pectoral fin with broad region of yellow pigmenta- tion; yellow color less obvious on distal portions of rays and on medial rays of fin. COLORATION IN ALCOHOL.—Overall ground coloration of relatively freshly collected specimens light tan. Dorsal surface of head with dense field of small dark chromatophores, giving region distinctly dusky appearance. Intensity of pigmentation more noticeable over brain, evidently as consequence of deep- lying pigmentation. Dense surface pigmentation continuing an- teriorly over snout and upper lip. Denser patch of pigmentation present anterior to nares. Specimens with darker overall head and body pigmentation having region immediately ventral to and posterior to orbit with pigmentation field interrupted by patch of faintly pigmented laterosensory canal segments. Dor- sal region of preopercle and infraorbitals with numerous small dark chromatophores. Variably developed pattern of dark pig- mentation present posterior to orbit; pattern ranging in form from discrete spot positioned along posterior margin of fourth and fifth infraorbitals, through irregular horizontal band limited to lateral surface of infraorbitals, to distinct stripe extending from posterior margin of orbit to rear of opercle. Scales of dorsolateral portion of body with small dark chro- matophores concentrated along posterior scale margin, giving overall reticulate pattern to body pigmentation in that region. Development of humeral mark highly variable. Overall form of 62 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY mark vertically elongate, with rotund, intensely pigmented re- gion centered immediately dorsal of lateral line. Intensely pig- mented region typically flanked ventrally and dorsally by less pigmented areas. Darkly pigmented region dorsal of humeral mark more apparent in smaller individuals and in larger speci- mens with less intense overall body pigmentation; pigmenta- tion field anterodorsally sloping and dorsally attenuate. Maxi- mum height of humeral mark approximately equal to that of two scales in that region. Ventral extension of main portion of humeral mark usually less obvious, pigmentation extending about one scale width ventral of main body of mark in form of ventrally attenuating patch of scattered chromatophores. Dark pigmentation along midlateral portion of body highly variable both ontogenetically and between comparably sized individu- als. Midlateral pigmentation consisting of two components, midlateral band of dark deep-lying chromatophores and re- gions of dark surface pigmentation. Surface pigmentation rang- ing from discrete, widely separated spots approximately size of pupil of eye, through variously coalesced spots and stripe seg- ments, to uninterrupted dark band extending from region of rear of opercle to base of middle caudal-fin rays. Highly devel- oped midlateral stripe subsumes humeral mark. Stripe continu- ous anteriorly with horizontal stripe extending from rear of or- bit to rear of opercle. Dorsal fin with membranes and margins of fin rays overlain by small dark chromatophores, particularly on distal two-thirds of dorsal-fin rays; intensity of dark pigmentation increasing on- togenetically, with number of rays with such pigmentation also increasing with body size. Basal portions of anal-fin rays out- lined by small dark chromatophores in medium-sized individu- als, rays nearly completely outlined in larger specimens. Cau- dal fin with fin rays and membranes overlain by small dark chromatophores, particularly in larger individuals. Distinct band of dark pigmentation on middle caudal-fin rays; band most intense basally where it forms irregular spot in many specimens. Basal portion of rays bordering middle caudal-fin rays less intensely pigmented. Distal portions of middle caudal- fin rays and of rays dorsal and ventral to them with margins more intensely pigmented. Pelvic and pectoral fins nearly hya- line in smaller individuals, dusky in larger specimens. ECOLOGY.—Saul (1975:106) reported that in the Rio Conejo, northeastern Ecuador, Creagrutus amoenus (identified therein as C. muelleri) was taken "in swift current over sand, gravel, or bedrock bottom. A few fish (4) were seined in a slow-flowing effluent of the lower lake." His analysis of stomach contents re- vealed that C. amoenus feeds on plant debris, insect debris, fish eggs, dragonfly nymphs, beetle larvae, caddisfly larvae, and fly larvae, including those of chironomids, with fly larvae the most abundant. The smallest mature female examined was a gravid 69.7 mm specimen with 0.9 mm ova captured in mid-June. At one locality in the Rio San Miguel basin, northeastern Ecuador, C. amoenus was captured sympatrically with C. flavescens (USNM 340973 and USNM 340986, respectively). DISTRIBUTION.—Creagrutus amoenus occurs in rivers of the Andean foothills of eastern Ecuador and southeastern Colom- bia (Figure 22, dots). REMARKS.—Fowler (1943a:239) described Creagrutus amoenus on the basis of a holotype and three paratypes. One of the paratypes of the species (ANSP 70500, 62.8 mm SL) is a specimen of C. flavescens. Gery (1972:66) noted in his original description of Creagru- tus boehlkei that "there exists a species from the Rio Ortuguesa in Colombia, C. amoenus Fowler, 1943, in which the overall appearance, particularly of the anterior head region, greatly re- sembles that of C. boehlkei sp. nov. C. amoenus has only 34 or 35 scales in total along the lateral line, however, and a different coloration" (our translation). Gery's citation of lateral line scales for C. amoenus was based on data presented in the origi- nal description of that species by Fowler (1943a:239) who evi- dently used different criteria for his lateral line scale counts than did Gery (1972). Examination of the holotypes of C. amoenus and C. boehlkei did not reveal differences in lateral line scale counts (Table 4). Similarly, the evident differences in pigmentation between the two nominal species noted by Gery (1972) fall within the range of variation for this feature within population samples from the type regions of each nominal spe- cies. Given the evident absence of differences between these nominal species, C. boehlkei is herein placed as a synonym of C. amoenus. Bohlke (1958:30) reported Creagrutus mulleri from various Ecuadorian localities, noting, however, that the material might represent another, possibly undescribed species. Gery (1972:65) identified Bohlke's material as C. boehlkei. These specimens are C. amoenus, with the exception of one speci- men, which is C. flavescens (ANSP 70500, in part). MATERIAL EXAMINED.—347 specimens (59, 35.4-91.2). COLOMBIA. Caquetd: Florencia (approximately 1°45'N, 75°35'W), Rio Ortuguasa (=Orteguaza), ANSP 70499, 1 (66.5; holotype of Creagrutus amoenus); ANSP 70500-70502, 2 (54.4-68.0; paratypes of Creagrutus amoenus, third paratype in lot is C. flavescens, see "Remarks," above); ANSP 70503, 1 (paratype of Creagrutus amoenus, specimen cleared and stained for bone); USNM 100762, 1. ECUADOR. "Oriente del Ecuador" (=eastern Ecuador), ZSM 28428, 1 (91.2, holotype of Creagrutus boehlkei); ZSM 28429, 2 (75.9-88.6, paratypes of Creagrutus boehlkei); ANSP 136915, 1 (76.5). Pastaza: Rio Conambo, tributary of Rio Ti- gre, ZMH 1757, 1 (81.0, paratype of Creagrutus boehlkei). Rio Danta, tributary to Rio Conambo (l°45'03"S, 76°47'04"W), USNM 311297, 2 (64.2-68.0); USNM 311339, 3 (1, 65.0; 1 specimen cleared and counterstained for cartilage and bone); MEPN 6608, 4; MEPN 6602, 3; MEPN 6607, 27. Rio Capo- tazo, tributary of upper Rio Pastaza (approximately 2°07'S, 77°27'W), ZMH 1758, 4 (62.5-70.0, paratypes of Creagrutus boehlkei); MCNG 2183.35, 2 (paratypes of Creagrutus boe- hlkei). Rio Villano, ZMH 1868, 1 (68.5, paratype of Creagru- tus boehlkei). Rio Villano, near Villano (l°30'S, 77°29'W), NUMBER 613 63 ANSP 75910, 1 (76.0); USNM 164045, 5; MEPN uncataloged, 7. Rio Tiguino basin, estero of Tiguino No. 3 (unnamed tribu- tary of Rio Tiguino; l°07'35"S, 76°56'52"W), MEPN 4599, 1; MEPN 6288, 5. Rio Landayacu, Moretecocha (01°35'12"S, 77°24'18"W), MEPN 7194, 12. Rio Metzera (=Rio Palora; 1°51'S, 77°49'W), MEPN 5357, 2. Rio Jandiayacu, MEPN 9649, 17. Napo: Rio Yasuni, Estero Triniti, 45 minutes by boat from Rocafuerte, USNM 311341, 4; MEPN 6497, 3. Rio Tut- apishco, near Loreto (0°38'S, 77°19'W), ANSP 75909, 1; ANSP 75908, 1; USNM 164070, 4 (2, 62.4-83.1; 1 specimen cleared and counterstained for cartilage and bone). Stream trib- utary to Rio Napo, approximately 15 mi (23 km) downstream of Missahuali (0°56'S, 77°30'W), ANSP 145981, 1 (81.0). Rio Cowi, near camp of oil drilling site in "Bloque 16 Pozo Cowi- Conoco" (0°08'10"S, 76°15'18"W), MEPN 4626, 27 (10, 51.3-76.5); USNM 340985, 4. Quebrada Yaucanoyacu, tribu- tary to Rio Payamino, downstream from Rio Tiquino (0°25'36"S, 77°19'24"W), FMNH 102997, 28 (10, 37.4-48.8). Quebrada Aulayacu, tributary to Rio Payamino (0°25'36"S, 77°19'24"W), FMNH 102998, 11. Quebrada to Rio Misahualli, in front of church at Cotundo (0°52'18"S, 77°50'12"W), FMNH 102979, 5. Rio Napo, near Puerto Francisco de Orel- lana (=Coca; 0°28'S, 76°58'W), USNM 340987, 6. Quebrada Yaucanayacu, tributary of Rio Payamino, 1 river km below mouth of Rio Tiquino (0°25'36"S, 77°19'24"W), MEPN 5267, 50. Quebrada Aulayacu, tributary of Rio Payamino, 0.8 river km below mouth of Rio Tiquino (0°25'36"S, 77°19'24"W), MEPN 5255, 10. Sucumbios: Rio Conejo, at bridge on road from Lago Agrio to Lumbaqui, near Santa Cecilia (O°3'3O"N, 77°02'W), MEPN 5265, 13. Rio Shushufindi, tributary to Rio Aguarico (0°10'S, 76°40'W), ANSP 137626, 4 (65.5-82.3). Santa Cecilia, Rio Conejo (approximately O ^ X 76°58'W), 1 km N of town, KU 13457, 7. Rio Bahita, 0.5 mi (0.8 km) N of Santa Cecilia, KU 13454, 6. Rio Coca drainage basin, headwa- ter tributary of Rio Dashino, approximately 9 km SW of Lum- baqui (by road) and 0.3 km S (0°0'3"S, 77°23'48"W), FMNH 102984, 46 (15, 35.4-53.7). Rio San Miguel basin, Rio La Ber- meja, in front of Communidad Shuor Chari (approximately O'MO'N, 76°25'W), MEPN 4640, 6; USNM 340986, 4. Creagrutus anary Fowler, 1913 FIGURES 22, 23, TABLE 5 Creagrutus anary Fowler, 1913:552, fig. 16 [type locality: Brazil, Madeira River (=Rio Madeira), approximately 200 miles (=320 km) E of longitude 62°20'W; see also under "Remarks," below, concerning reported locality]; 1948:82, fig. 87 [literature compilation]; 1975:25 [literature compilation].— Eigenmann, 1927:423 [Madeira River, based on Fowler, 1913].—Gery, 1964:62 [in key]; 1977:407 [Rio Madeira, C. hildebrandi Schultz cited as possible junior synonym].—Bdhlke, 1984:42 [holotype reported missing, paratype cited as cleared and stained].—Cala, 1990:92 [as possible synonym of C. hildebrandi following Gery, 1977].—Chang and Ortega,1995:2 [Peru, Department of Madre de Dios].—Chang, 1998:22 [southeasternPeru]. DIAGNOSIS.—The combination of the possession of premax- illary dentition arranged in the three ecomponents generalized TABLE 5.—Morphometrics and meristics of Creagrutus anary: (A) paratype of C. anary, ANSP 39291 (specimen in poor condition and holotype of the species is apparently lost; see "Remarks" within species account); and (B) all other specimens of C. anary from which counts and measurements were taken (n= 10). Dashes indicate values that could not be determined because of damage to paratype. Characters Standard length 1. Snout to anal-fin origin 2. Snout to pelvic-fin insertion 3. Snout to pectoral-fin insertion 4. Snout to dorsal-fin origin 5. Dorsal-fin origin to hypural joint 6. Dorsal-fin origin to anal-fin origin 7. Dorsal-fin origin to pelvic-fin insertion 8. Dorsal-fin origin to pectoral-fin insertion 9. Caudal peduncle depth 10. Pectoral-fin length 11. Pelvic-fin length 12. Dorsal-fin length 13. Anal-fin length 14. Head length 15. Postorbital head length 16. Snout length 17. Bony orbital diameter 18. Interorbital width Lateral line scales Scale rows between dorsal-fin origin and lateral line Scale rows between anal-fin origin and lateral line Predorsal median scales Branched dorsal-fin rays Branched anal-fin rays Branched pelvic-fin rays Pectoral-fin rays Vertebrae A B Morphometrics -25.0 - - - - - - - - - - - - - - - - - - 25.0-44.5 60.7-64.5 44.3-47.5 21.0-23.8 44.0-48.3 54.0-58.3 28.5-32.3 24.1-27.5 30.5-32.6 9.7-11.4 18.9-19.4 14.8-16.2 21.8-23.5 18.4-19.5 23.5-26.1 39.4-42.5 24.9-26.4 33.9-37.4 30.7-33.0 Meristics _ i - 2 _3 _4 85 12" V 138 39 40-43 4 3 8-9 8 10-12 6-7 12-14 3 8 ^ 0 1 Reported by Fowler (1913) as 40 in paratype and 42 in holotype. 2Reported by Fowler (1913) as 5 in both paratype and holotype. 3Reported by Fowler (1913) as 3 in paratype and 4 in holotype. 4Reported by Fowler (1913) as 9 in paratype and 8 in holotype. 5Same value reported by Fowler (1913) for holotype. ^Reported by Fowler (1913) as 11 in both paratype and holotype. 7Same value reported by Fowler (1913) for holotype. 8Same value reported by Fowler (1913) for holotype. for most species of Creagrutus without a pronounced gap be- tween the first and second teeth of the primary tooth series of the premaxilla, 6 teeth in the primary series of each premaxilla, 2 to 4 maxillary teeth, 4 or 5 teeth on each dentary, 8 or 9 me- dian predorsal scales, 40 to 43 lateral line scales without a lamellar process over each pore, 4 scale rows between the dor- sal-fin origin and the lateral line, 10 to 12 branched anal-fin rays, 7 or 8 gill rakers on the upper limb of the first gill arch, the distance from the snout to the pectoral-fin insertion (21.0%-23.8% of SL), the snout length (24.9%-26.4% of HL), the bony orbital diameter (33.9%-37.4% of HL), the interor- bital width (30.7%-33.0% of HL), the lack of contact between 64 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY the ventral margin of the third infraorbital and the horizontal limb of the preopercle, the possession of a distinct spot of dark pigmentation at the base of the middle caudal-fin rays, the moderately vertically elongate humeral mark without a second- ary, dorsally situated patch of pigmentation, the absence of a distinct patch of pigmentation on the dorsal fin, and the lack of a series of dark spots along the midlateral surface of the body distinguishes Creagrutus anary within the clade formed by Creagrutus and Piabina. DESCRIPTION.—Morphometric and meristic data for Crea- grutus anary in Table 5. Head and body moderately robust, body more so in larger females. Greatest body depth at vertical through dorsal-fin origin in most individuals, shifted distinctly anteriorly in specimens with distended abdomens. Dorsal pro- file of head convex from margin of upper lip to vertical through anterior margin of orbit, nearly straight from that point to tip of supraoccipital spine. Interorbital region distinctly convex trans- versely. Predorsal profile slightly convex, without obvious change in alignment relative to that of head. Predorsal region of body with obtuse median ridge proximate to dorsal-fin origin. Ventral profile of head slightly convex anteriorly, with barely obvious obtuse angle at anteroventral corner of dentary (angle in ventral profile of dentary not apparent in fig. 16 of Fowler, 1913); head profile nearly straight from that point to isthmus. Profile of prepelvic region of body variably convex, more so in larger specimens. Prepelvic region of body distinctly flattened transversely. Head obtusely pointed in lateral view, moderately com- pressed in dorsal view. Upper jaw slightly longer than, and overhanging, lower jaw. Anteromedial portion of snout fleshy with scattered papillae. Scattered papillae distributed over lat- eral surface of jaw with papillae more concentrated along ven- tral margin of jaw anteriorly and on plicae and folds extending between outer and medial premaxillary teeth. Lower lip fleshy, with papillae concentrated along dorsal margin and scattered papillae anteromedially. Infraorbital series relatively well developed. Ventral margin of third infraorbital contacting or nearly contacting horizontal limb of preopercle. Posterior margins of third and fourth in- fraorbitals falling slightly short of vertical limb of preopercle; posterior margin of fifth infraorbital in, or nearly in, contact with vertical limb of preopercle. Premaxillary dentition in three series: primary row slightly sigmoid, with 6 teeth, without pronounced gap between first and second tooth of series and with medial teeth of contralat- eral series distinctly separated; triangular cluster of 3 larger teeth with medial teeth of contralateral clusters nearly in con- tact; and single tooth of form similar to that of primary series occurring lateral to or slightly anterolateral to fourth tooth of premaxillary row. Maxilla with 2 to 4 tricuspidate teeth. Den- tary with 4 or 5 teeth; 3 anterior teeth distinctly larger and tri- cuspidate with middle cusp much larger; second tooth about twice as high and wide as first tooth and three times as high and four times as wide as third tooth; fourth and fifth teeth (when 5 teeth present) graded in size, fourth always tricuspidate, fifth tricuspidate or with small posterior cusp missing. Dorsal-fin rays ii,8 in all examined specimens. Dorsal-fin or- igin at, or approximately at, vertical through pelvic-fin inser- tion. Profile of distal margin of dorsal fin slightly concave. Anal-fin rays ii or iii,10-12. Anal-fin hooks present on first branched anal-fin ray in mature males. Pectoral-fin rays i,l 1-13. Tip of pectoral fin extending approximately two-thirds to three-fourths of distance to pelvic-fin insertion. Pelvic-fin rays i,6,i or i,7. Tip of pelvic fin extending to anus or to anal- fin origin. Gill rakers 7-8+10-11. COLORATION IN ALCOHOL.—Ground coloration of speci- mens yellow-tan. Dorsal surface of the head with few surface dark chromatophores scattered over anterodorsal region of head and over snout, otherwise without surface pigmentation. Series of very dark, deep-lying stellate chromatophores overly- ing dorsal portion of brain. Anterior portion of brain overlain by contralateral, horizontally elongate patches of dark chro- matophores. Region anterior to nostrils with crescent-shaped patch of dark chromatophores. Anteroventral region of orbit outlined by variably obvious narrow series of dark chromato- phores. This series not continuous with chromatophore field anterior to nostrils, nor continuing around ventral and dorsal margins of orbits as in many congeners. Sixth infraorbital and proximate portion of opercle with few scattered dark chromato- phores. Scales of anterodorsal portion of body outlined by single se- ries of dark chromatophores. Middorsal region with field of scattered chromatophores. Obscure midlateral stripe formed of scattered dark chromatophores extending from approximately vertical through dorsal-fin origin to caudal peduncle. Humeral mark moderately obvious and vertically elongate, with variable anterior and posterior margins. Ventral margin of humeral mark extending approximately to lateral line; dorsal margin less dis- crete, with variably developed series of scattered dark chro- matophores extending dorsally from main body of mark. Dorsal fin with anterior margin of second unbranched ray outlined by dark chromatophores and with membranes between distal one-half to two-thirds of anterior branched rays with scattered chromatophores. Anal-fin rays with chromatophores at base of anterior branched rays. Middle caudal-fin rays with obscure horizontal stripe; stripe most concentrated anteriorly, giving appearance of distinct spot. Pectoral and pelvic fins hya- line. ECOLOGY.—Stomach contents of two specimens prepared for clearing and staining consisted mostly of parts of small seeds, with limited amounts of insect parts and insect larvae. DISTRIBUTION.—Creagrutus anary is known from the mid- dle portions of Rio Madeira basin in Brazil (Figure 22, squares). The species also has been reported from further up- stream in the Department of Madre de Dios, Peru (Chang and Ortega, 1995:2). NUMBER 613 65 FIGURE 23.—Creagrutus anary, MZUSP 35604, 44.5 mm SL; Brazil, Rondonia, Rio Madeira, Cachoeira de Santo Antonio (8°43'S, 63°55'W). COMPARISONS.—In addition to Creagrutus anary, only one other Creagrutus species, C. petilus, is known to occur in the central portions of the Rio Madeira basin. Creagrutus anary and C. petilus are readily distinguishable in overall appearance, number of lateral line scales, and head length, snout length, and interorbital width (compare Tables 5 and 46). REMARKS.—Fowler's description (1913:552) of Creagrutus anary was based on a holotype and single paratype collected together with it in the Rio Madeira system (see discussion be- low with respect to problematic reported type locality). Bohlke (1984:42) reported that the holotype (ANSP 39290) was miss- ing and that the single paratype (ANSP 39291) had been cleared and stained for bone. Examination reveals that the paratype apparently had desiccated at some point prior to being stained. Whether it also had been cleared is uncertain, but if it was so prepared, the residual soft tissues have subsequently darkened to a degree that precludes the examination of internal features. Despite the evident loss of the holotype and the limited de- gree of information available from the paratype, the data avail- able from the latter specimen (Table 5) plus information from the original description lead us to equate the material herein considered to be C. anary with that species. These specimens agree with the data provided in the original description of the species and demonstrate the unusual dark pigmentation at the base of the middle caudal-fin rays characteristic of C. anary. Type locality and collector for Creagrutus anary were re- ported by Fowler (1913:554) as "Madeira River, about 200 miles east of Long[itude]. W. 62°2\ Brazil" by E.A. Smith. This approximate locality lies in the lower portions of the Rio Madeira. Bohlke (1955:8-12) discussed the problems with var- ious localities cited by Fowler for the specimens collected by Smith. Based on the evidence, Bohlke reasonably proposed that the actual distance was 20 rather than 200 miles east of longitude 62°20'W. Such an interpretation shifts the type local- ity for C. anary further upstream along the Rio Madeira and places it significantly closer to the other collecting sites with exact locality information provided by the collector, E.A. Smith. All nontype material of C. anary examined in this study originated in the middle portions of the Rio Madeira basin in the area proximate to where the majority of Smith specimens were collected, a distribution in agreement with Bohlke's sug- gestion that the type locality cited in the original description of the species was problematic. Fowler (1913:555) reported the paratype of C. anary as "length 34 mm." As noted by Bohlke (1984:42), this was prob- ably total length. The paratype (ANSP 39291) is instead ap- proximately 25 mm SL. Gery (1977:407), presumably based mostly on information in the literature, proposed that Creagrutus hildebrandi, de- scribed by Schultz (1944:330) from the Lago Maracaibo basin of northern Venezuela, was as a possible synonym of C. anary, which was originally described a considerable distance away in the Rio Madeira basin. Cala (1990:92) followed Gery in this tentative synonymy. Although the pigmentation patterns of the two species are quite similar, C. hildebrandi is endemic to the Lago Maracaibo basin and adjoining independent Caribbean versant coastal drainages of northwestern Venezuela (Harold and Vari, 1994, fig. 13). The two species differ in a series of features, most notably in the numbers of lateral line scales (34 to 37 in C. hildebrandi versus 40 to 43 in C. anary) and verte- brae (35 to 37 in C. hildebrandi versus 38 to 40 in C. anary). MATERIAL EXAMINED.—19 specimens (10,25.0-44.5). BRAZIL. Amazonas: Madeira River (=Rio Madeira), ap- proximately 200 miles (=320 km) E of longitude 62°20'W (see under "Remarks," above, concerning the reported locality), ANSP 39291,1 (approximately 25 mm, paratype of Creagrutus anary; specimen stained for bone and perhaps cleared, in poor condition). Mouth of Igarape Puruzinho (7°24'S, 63°00'W), MZUSP 35590, 1. Rio Madeira, Ilha do Puruzinho (7°24'S, 63°00'W), MZUSP 35615, 5 (1, 30.5). Rondonia: Rio Madeira, Calama (8°04'S, 62°52'W), MZUSP 30575, 4 (1, 29.0). Rio Madeira, Parana do Caraparu, Calama (8°04'S, 62°52'W), MZUSP 31875, 2 (1, 25.0). Rio Madeira, Cachoeira de Santo Antonio (8°43'S, 63°55'W), MZUSP 35604, 6 (34.1^4.5: 2 specimens cleared and counterstained for cartilage and bone). 66 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY Creagrutus atratus, new species FIGURES 22.24,25. TABLE 6 DIAGNOSIS.—The combination of the possession of pre- maxillary dentition arranged in the three components general- ized for most of the species of Creagrutus and Piabina with- out a distinctly larger gap between the first and second teeth in the primary series, typically 6 teeth in primary series of each premaxilla, 3 or 4 maxillary teeth, 5 or 6 teeth on each dentary, 10 to 13 median predorsal scales, 38 to 42 lateral line scales without a lamellar process over each pore, 4, rarely 5, scale rows between the dorsal-fin origin and the lateral line, 3 or 4 scale rows between the anal-fin origin and the lateral line, 9 to 13 branched anal-fin rays, 6 to 8 gill rakers on the upper limb and 8 to 10 gill rakers on the lower limb of the first gill arch, 38 or 39 vertebrae, the postorbital head length (45.5%-52.8% of HL), the bony orbital diameter (24.4%-32.0% of HL), the interorbital width (34.0%-37.9% of HL), the caudal peduncle depth (12.1%-13.6% of SL), the two post-anal median scales to the anal-fin origin, the contact or near contact between the ventral margin of the third infraorbital and the horizontal limb of the preopercle, the lack of a distinct spot of dark pigmenta- tion at the base of the middle caudal-fin rays, the vertically elongate, ventral ly tapering humeral mark without a second- ary, dorsally situated patch of pigmentation, the absence of a distinct patch of pigmentation on the dorsal fin, and the lack of a series of dark spots along the midlateral surface of the body distinguishes Creagrutus atratus within the clade formed by Creagrutus and Piabina. DESCRIPTION.—Morphometric and meristic data for Crea- grutus atratus in Table 6. Head and body relatively robust, in- creasingly so in larger specimens. Greatest body depth at dor- sal-fin origin in specimens of up to about 35 mm SL, shifted anteriorly approximately to midway between pectoral- and pelvic-fin insertions in larger specimens with more rotund pre- pelvic profiles. Dorsal profile of head distinctly convex from margin of upper lip to vertical through anterior margin of eye, straight or very slightly convex from that point to tip of su- praoccipital spine. Interorbital region distinctly rounded over- all transversely, but with some median flattening in larger specimens. Dorsal profile of body nearly straight from tip of supraoccipital spine to dorsal-fin origin in specimens smaller than approximately 35 mm SL, increasingly convex in larger specimens, with distinct change in profile relative to that of the head. Predorsal region of body with obtuse median ridge proximate to dorsal-fin origin. Ventral profile of head with ob- tuse angle at anteroventral corner of dentary, approximately straight from that angle to isthmus. Prepelvic region of body slightly convex in specimens smaller than 30 mm SL, convex- ity increasing in larger specimens. Head obtusely pointed in lateral view and somewhat com- pressed in dorsal view. Upper jaw longer than, and overhang- ing, lower jaw. Papillae in some individuals much more broadly distributed than in many congeners. Smaller speci- TABLE 6.—Morphometrics and meristics of Creagrutus atratus, new species: (A) holotype of C. atratus, ICNMHN 4158; and (B) paratypes of C. atratus (n =49). Standard length is expressed in mm; measurements 1 to 14=percentages of standard length; 15 to 18=percentages of head length. Characters Standard length 1. Snout to anal-fin origin 2. Snout to pelvic-fin insertion 3. Snout to pectoral-fin insertion 4. Snout to dorsal-fin origin 5. Dorsal-fin origin to hypural joint 6. Dorsal-fin origin to anal-fin origin 7. Dorsal-fin origin to pelvic-fin insertion 8. Dorsal-fin origin to pectoral-fin insertion 9. Caudal peduncle depth 10. Pectoral-fin length 11. Pelvic-fin length 12. Dorsal-fin length 13. Anal-fin length 14. Head length 15. Postorbital head length 16. Snout length 17. Bony orbital diameter 18. Interorbital width Lateral line scales Scale rows between dorsal-fin origin and lateral line Scale rows between anal-fin origin and lateral line Predorsal median scales Branched dorsal-fin rays Branched anal-fin rays Branched pelvic-fin rays Pectoral-fin rays Vertebrae A B Morphometrics 86.4 60.5 48.0 22.6 45.8 57.1 31.1 27.9 33.4 12.2 19.6 13.7 21.2 15.9 24.5 50.0 28.3 25.9 35.4 35.4-91.5 60.2-67.6 47.0-54.0 22.3-27.6 44.8-49.5 54.3-59.2 29.6-35.3 27.4-34.0 32.3-36.2 12.1-13.6 18.4-21.3 13.3-16.7 19.6-23.5 15.5-20.9 25.5-28.1 45.5-52.8 26.6-31.6 24.4-32.0 34.0-37.9 Meristics 41 4 32 12 8 12 6 12 38 38-42 4-5 ' 3_42.3 10-13 8 9-13" 5-75 11-14 38-39 'Five scale rows above lateral line present in only 5 of 49 paratypes. 2Larger specimens with short sheath of small scales along anterior portion of base of anal fin, giving appearance of an additional row of scales. 3Four scale rows below lateral line present in only 4 of 49 paratypes. 4Nine anal-fin rays present in only 3 of paratypes, one of these 3 with dis- tinct gap within anal-fin ray series. 5Five branched rays present in 1 paratype; 7 branched rays present in 1 para type. mens with papillae scattered ove dorsal portion of head, snout, and upper and lower lips. Larger individuals with papillae field more extensive. Some individuals with papillae on dorsal and lateral surfaces of head, including infraorbitals and oper- cular series, with papillae also present on upper lip and jaw, on folds and plicae extending between outer and medial premax- illary teeth, and on anterior and lateral surfaces of lower jaw. Occasionally papillae extending onto scales of anterodorsal portions of body. Variation in degree of development of papil- lae field not correlated with any externally obvious sexual dif- ferences. No correlation found between numbers of papillae and body size, with comparable-sized specimens collected at same time and location showing significant differences in the extent of papillae fields. Papillae fields poorly developed in NUMBER 613 67 FIGURE 24.—Creagrutus atratus, new species, holotype, ICNMHN 4158, 86.4 mm SL; Colombia, Cundinama- rca, Rio Caqueza, tributary to Rio Negro, about 2 km upstream of village of Caqueza. FIGURE 25.—Creagrutus atratus, new species, USNM 353865, 69.5 mm SL; Colombia, Cundinamarca, Rio Meta basin, mouth of Rio Caqueza. some available population samples, perhaps reflecting season- ality in their presence. Infraorbital series relatively well developed. Ventral margin of third infraorbital varyingly curved, deepest portion of third infraorbital contacting, or nearly contacting, horizontal limb of preopercle. Posterior margins of third through fifth infraorbit- als distinctly separated from vertical limb of preopercle. Premaxillary dentition in three series: primary series straight to slightly curved, typically with 6 tricuspidate teeth, but with 5 teeth present as variant on one, or rarely both, premaxillae in some specimens, without pronounced gap between first and second tooth of series but with medial tooth separated from contralateral series by distinct gap; triangular cluster of 3 tricus- pidate teeth, all somewhat to distinctly larger than those of pri- mary tooth row; and single tooth comparable in form and size to those of primary series occurring lateral to fourth tooth of primary premaxillary row (when 6 teeth present in primary row) or in area of contact of third and fourth teeth (when 5 teeth present in primary row); second tooth lateral to primary pre- maxillary row present on one side of head in one specimen. Maxilla with 3 tricuspidate teeth in smaller individuals, with 3 or 4 teeth in larger specimens. Dentary with 5 or 6 teeth. Three anterior dentary teeth distinctly larger and tricuspidate with central cusp largest. Second tooth slightly longer vertically than first tooth and about twice as high as third tooth. Fourth and fifth or sixth teeth slightly tricuspidate and graduated in size. Dorsal-fin rays typically ii,8; iii,8 in one specimen. Dorsal- fin origin slightly anterior to vertical through pelvic-fin inser- tion. Profile of distal margin of dorsal fin straight to slightly concave, concavity typically more pronounced in larger indi- viduals. Anal-fin rays ii,9-13 or iii, 11-13. Profile of distal mar- gin of anal fin concave, with slight anterior lobe developed in 68 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY some specimens. Anal-fin hooks present in mature males of many congeners not present in any of examined specimens of present species. Pectoral-fin rays i, 10-13. Tip of pectoral fin reaching posteriorly approximately two-thirds of distance to pelvic-fin insertion. Pelvic-fm rays i,5-7, typically i,6. Tip of pelvic fin reaching posteriorly to anal-fin insertion in some smaller individuals, falling 2 or 3 scales short of that point in larger specimens. Pelvic-fin hooks present in mature males of many congeners not present in any of examined specimens. Body scales sometimes with papillae (see above); scales ex- tending onto basal region of central portions of each caudal lobe. Gill rakers 6-8 + 8-10. Some larger individuals have gill rak- ers on lower portion of first gill arch forked distally. COLORATION IN ALCOHOL.—Overall dark pigmentation highly variable between samples and within certain lots. Ground coloration tan. Small specimens with light overall head and body coloration having dense field of dark chromatophores overlying brain and less concentrated chromatophore field over anterodorsal portion of head. Other small individuals with more intense overall pigmentation with nearly solid dark pig- mentation field on dorsal surface of head. Larger specimens with continuous chromatophore field on dorsal surface of head, but with overall darkness function of intensity of individual chromatophores. Lighter specimens showing crescent-shaped darker chromatophore field anterior to nostril and posteroven- trally angled band of dark chromatophores extending from un- der nostrils to below anteroventral portion of orbit. Both of these pigmentation patterns subsumed into darker head pig- mentation in individuals with overall darker coloration. Dis- persed dark chromatophores on dorsal portions of first and sec- ond infraorbitals, dorsal portion of third infraorbitals, and over fourth and fifth infraorbitals; chromatophore field extending more ventrally on first to third infraorbitals in larger speci- mens. Region of cheek between posterior margin of third in- fraorbital and vertical limb of preopercle with vertically elon- gate chromatophore field continuous dorsally with dark pigmentation situated posterior of orbit. Opercle pigmented other than along its posteroventral one-third in some speci- mens; pigmentation forming variably shaped, vertically elon- gate dark mark; spot more extensive in individuals with overall darker pigmentation. Scales of dorsolateral portion of body with dark chromato- phores concentrated along margin of scales and forming reticu- late pattern. Humeral mark vertically elongate and ventrally ta- pering. Mark extending from about one scale ventral of lateral line to one and one-half scales from dorsal midline. Humeral mark distinct in lightly colored specimens, especially smaller individuals, somewhat less distinct, albeit still obvious, in most darker specimens, and nearly completely subsumed into overall body pigmentation in very dark individuals. Broad midlateral stripe extending from posterior margin of humeral mark to rear of caudal peduncle. Pigmentation of stripe consisting both of band of deep-lying, diffuse, dark coloration and of discrete, dark chromatophores overlying scales. Distal one-fourth to two-thirds of dorsal-fin rays with small dark chromatophores outlining rays and ray segments; scat- tered chromatophores over intervening membranes, usually not extending as far basally as pigmentation located along ray mar- gins. Specimens with particularly dark overall pigmentation having dusky region extending across middle portion of dorsal fin. Caudal-fin rays outlined by chromatophores, giving fin dusky appearance; pigmentation more intense in overall darker specimens, with middle caudal-fin rays darker than remainder of fin, albeit not forming discrete stripe; ventral lobe of caudal fin usually more intensely pigmented than dorsal lobe, but with difference less obvious in very dark specimens. Anal fin rang- ing from hyaline to having distal one-half to two-thirds of rays outlined by small dark chromatophores with scattered chro- matophores on intervening membranes. Individuals with par- ticularly dark overall pigmentation with region of dusky pig- mentation extending along middle section of anterior half of fin. Pelvic fin ranging from hyaline to having rays outlined by small, dark chromatophores. Pectoral-fin rays outlined by chro- matophores, more so in darker individuals. ETYMOLOGY.—The specific name, atratus, from the Latin for dressed in black, refers to the dark coloration of the type se- ries and many of the available specimens. ECOLOGY.—Creagrutus atratus occurs with C. bolivari at least in two localities, as shown by some examined lots. DISTRIBUTION.—Creagrutus atratus occurs in the western portions of the Rio Orinoco basin in the foothills of the eastern Cordillera of the Andes (Figure 22, stars). MATERIAL EXAMINED.—97 specimens (55, 35.4-91.5). HOLOTYPE.—COLOMBIA. Cundinamarca: Rio Meta basin, Rio Caqueza, tributary to Rio Negro, about 2 km upstream of village of Caqueza (latter at 4°25'N, 73°57"W), collected by A.M.C. Silfvergrip, 5 Dec 1987, ICNMHN 4158, 1 (86.4). PARATYPES.—49 specimens (49, 35.4-91.5). COLOMBIA. Cundinamarca: Rio Meta basin, Rio Caqueza, tributary to Rio Negro, about 2 km upstream of village of Caqueza (latter at 4°25'N, 73°57'W), collected with holotype, NRM 16842, 19 (48.5-89.3); USNM 353866, 5 (51.3-80.8). Rio Meta basin, backwater of Rio Negro, at Caqueza (4°27'N, 73°53'W), collected by J.E. Bohlke et al., 4 Apr 1975, ANSP 134080, 5 (49.3-69.6). Rio Meta basin, Rio Sanane, where emptying into Rio Negro (approximately 4°20'N, 73°52'W), collected by A.M.C. Silfvergrip, 19 Dec 1987, NRM 16843, 15 (35.4-91.5); USNM 353867, 5 (47.5-67.7; 2 specimens cleared and counterstained). NONTYPE SPECIMENS.—47 specimens (5,46.3-70.1). COLOMBIA. Cundinamarca: Rio Meta basin, mouth of the Rio Caqueza, where emptying into Rio Negro, NRM 16841, 32; USNM 353865, 5 (46.3-70.1). Meta: Rio Meta basin, Rio Guayuriba, where crossed by road between Villavicencio and Acacias, NRM 16852, 2; NRM 16851, 5. Rio Meta basin, Rio Guayuriba, approximately 4 km south of village of Santa Rosa, NRM 16850, 3. NUMBER 613 69 Creagrutus atrisignum Myers, 1927 FIGURES 22, 26, TABLE 7 Creagrutus bem[not of Eigenmann, 1911].—Eigenmann, 1927:421 [misidenti- fication] [in part, citation of species in Rio Tocantins basin; specimen from Brazil, Rio Tocantins, Cachoeira de Valpa de Rio Nova, near Piabana; not ci- tations of C. beni from other regions of South America]. Creagrutus atrisignum Myers, 1927:116 [type locality: [Brazil], Goyaz (= Goias), upper Rio Maranhao (upper Rio Tocantins basin)].—Eigenmann and Myers, 1929:549 [based on Myers, 1927].—Fowler, 1948:83 [literature com- pilation]; 1975:25 [literature compilation].—Gery, 1977:407, 410 [in key, drawing of paratype]. DIAGNOSIS.—The form of the dark humeral mark in Crea- grutus atrisignum consisting of a primary variably horizontally elongate central portion and a distinct, smaller, secondary dor- sal component, with the two components joined in some indi- viduals by a narrow band of dark chromatophores is autapo- morphic within the assemblage consisting of Creagrutus and Piahina. Creagrutus atrisignum is further distinguished in the clade consisting of Creagrutus and Piabina by the combination of the possession of premaxillary dentition arranged in the three components generalized for most of the species of Crea- grutus and Piabina without a pronounced gap between the first and second teeth of the primary series, 2 to 4 maxillary teeth, 4 teeth in each dentary, 9 to 11 median predorsal scales, 5 scale rows between the dorsal-fin origin and the lateral line, 9 or 10 branched anal-fin rays, 2 post-anal scales anterior to the anal- fin origin, the well-developed third infraorbital with its ventral margin contacting the horizontal limb of the preopercle, the lack of a series of dark spots along the midlateral surface of the body, the discrete humeral marks whose two components, al- though encompassing a vertically elongate area, do not form a vertical bar, and the lack of a discrete patch of dark pigmenta- tion on the anterior portion of the middle of the dorsal fin. DESCRIPTION.—Morphometric and meristic data for Crea- grutus atrisignum in Table 7. Head and body moderately robust (Figure 26). Greatest body depth at, to somewhat anterior of, dorsal-fin origin; typically more anterior in larger specimens. Dorsal profile of head smoothly convex from margin of upper lip to vertical through posterior nostril, straight from that point to tip of supraoccipital spine. Interorbital region smoothly con- vex transversely. Anterior portion of predorsal region of body continuing profile of posterior portion of head; profile becom- ing more curved posteriorly but without pronounced change in alignment relative to that of head in most specimens. Predorsal region of body somewhat flattened transversely anteriorly, with median ridge proximate to dorsal-fin origin. Ventral profile of head with variably obvious obtuse angle at anteroventral comer of dentary, nearly flat from angle to isthmus. Prepelvic profile of body convex, more so in many larger specimens. Head obtusely pointed in lateral view, less so in dorsal view. Upper jaw distinctly longer than, and overhanging, lower jaw. Anteromedial portion of snout fleshy with scattered papillae. Papillae more concentrated on fleshy upper lip, especially TABLE 7.—Morphometrics and meristics of Creagrutus atrisignum: (A) holo- type of C. atrisignum, CAS 41339 (formerly IU 17679); and (B) all other spec- imens of C. atrisignum from which counts and measurements were taken (n= 30). Standard length is expressed in mm; measurements 1 to 14=percentages of standard length; 15 to 18=percentages of head length. Characters Standard length 1. Snout to anal-fin origin 2. Snout to pelvic-fin insertion 3. Snout to pectoral-fin insertion 4. Snout to dorsal-fin origin 5. Dorsal-fin origin to hypural joint 6. Dorsal-fin origin to anal-fin origin 7. Dorsal-fin origin to pelvic-fin insertion 8. Dorsal-fin origin to pectoral-fin insertion 9. Caudal peduncle depth 10. Pectoral-fin length 11. Pelvic-fin length 12. Dorsal-fin length 13. Anal-fin length 14. Head length 15. Postorbital head length 16. Snout length 17. Bony orbital diameter 18. Interorbital width Lateral line scales Scale rows between dorsal-fin origin and lateral line Scale rows between anal-fin origin and lateral line Predorsal median scales Branched dorsal-fin rays Branched anal-fin rays Branched pelvic-fin rays Pectoral-fin rays Vertebrae A B Morphometrics 46.0 64.6 49.1 23.9 51.1 56.5 32.6 28.5 33.9 12.2 20.9 16.1 22.6 16.4 27.0 44.4 28.6 32.3 30.6 37.2-55.2 61.5-68.0 45.4-49.6 22.9-26.2 47.5-51.3 52.9-56.9 29.3-32.8 25.7-28.9 31.2-35.0 11.2-12.3 19.1-21.9 14.8-17.4 20.6-23.5 16.4-19.4 25.5-28.0 44.1^*5.8 28.4-31.7 31.4-37.1 30.4-33.3 Meristics 37 5 3 9 8 10 6 12 36 36-38 5 3 9-11 8 9-10 6 12-13 35-37 along ventral margin of lip and on folds and plicae extending between outer and medial premaxillary teeth. Lower lip very fleshy with numerous papillae distributed over dorsal and ante- rior surfaces. Infraorbital series well developed. Ventral margin of third in- fraorbital contacting horizontal limb of preopercle. Posterior margins of third through fifth infraorbitals slightly separated from vertical limb of preopercle. Premaxillary dentition in three series: primary row curved, usually with 6, occasionally 5, tricuspidate teeth without pro- nounced gap between first and second tooth of series but with medial tooth separated from medial tooth of contralateral series by distinct gap; triangular cluster of 3 teeth distinctly larger than those of primary series; and single tooth of form similar to that of primary series occurring lateral to fourth tooth of pri- mary premaxillary row (when 6 teeth present in primary series) or lateral to gap between third and fourth teeth (when 5 teeth present in primary series). Maxilla with 2 to 4 tricuspidate teeth. Dentary with 4 tricuspidate teeth, anterior and posterior cusps barely apparent on posteriormost tooth; second tooth dis- 70 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY tinctly larger than first and about twice as high as third; fourth tooth distinctly smaller than third. Dorsal-fin rays ii,8 in all specimens. Dorsal-fin origin ap- proximately at vertical through pelvic-fin insertion. Profile of distal margin of dorsal fin straight to very slightly concave. Anal-fin rays ii,9-10 or iii,9. Profile of distal margin of anal fin straight to slightly concave. Mature males with hooks typically present on anterior 3 or 4 branched rays, hooks rarely present on fifth branched anal-fin ray. Pectoral-fin rays i,11-12. Tip of pectoral fin extending approximately two-thirds distance to pelvic-fin insertion. Pelvic-fin rays i,6,i in all specimens. Tip of pelvic fin extending to anal-fin origin in smaller specimens, falling short of that point and extending posteriorly only to anus in larger individuals. Mature males with hooks present on all branched pelvic-fin rays. Gill rakers 7-8+ 11-13. COLORATION IN ALCOHOL.—Head and body of specimens retaining guanine on scales somewhat silvery. Ground colora- tion of specimens lacking guanine on scales tan. Dorsal surface of head with scattered, dark, small chromatophores. Large stel- late chromatophores overlying membranes of dorsal surface of brain. Dorsal surface of snout and upper lip with field of dense chromatophores; chromatophore field more concentrated ante- rior to nostrils, but only forming discrete crescent-shaped dark pigment patch in larger specimens. Region anteroventral to nostrils with field of chromatophores, but this pigmentation not continuing around ventral and posterior margins of orbit as in many congeners. Dorsal portions of opercle and infraorbital se- ries with patch of chromatophores forming irregular horizontal stripe behind orbit. Scales of dorsolateral surface of body in specimens over ap- proximately 35 mm SL with basal patch of dark chromato- phores and irregular series of chromatophores along distal mar- gin. Region between chromatophore fields hyaline. Overall pigmentation of scales most prominent immediately ventral of dorsal-fin base, and somewhat less so middorsally. Humeral mark dark at all examined sizes, shape ontogenetically vari- able, rotund in specimens of approximately 20-30 mm SL, slightly horizontally elongate in some specimens of approxi- mately 35 mm SL, and distinctly horizontally elongate and usually wider along its posterior one-half in larger individuals. Variably present series of dark chromatophores less concen- trated than those of main body of humeral mark extending ven- trally from main portion of mark in larger individuals. Second patch of concentrated chromatophores situated approximately one scale dorsal of anterior portion of main humeral mark. Sec- ondary patch of humeral pigmentation absent in specimens of 20-30 mm SL, slightly developed in specimens of approxi- mately 35 mm SL, and obvious in larger specimens. Two areas of dark humeral pigmentation ranging from completely sepa- rated to joined by a thin vertical band of dark chromatophores. Midlateral body stripe formed by both surface and deep-lying chromatophores. Anterior portion of stripe diffuse, extending anteriorly approximately to under middle of dorsal fin in smaller individuals, nearly to posterior margin of humeral mark in larger specimens. Stripe typically most intense on posterior one-half of body and extending onto basal portions of middle caudal-fin rays. Dorsal fin with last unbranched and anterior branched rays overlain with dark chromatophores and with distal one-half of following 3 or 4 branched rays with scattered, dark chromato- phores. Membranes of pigmented rays with numerous dark chromatophores anteriorly and scattered chromatophores pos- teriorly. Chromatophores on rays and membranes in combina- tion form a diffuse, but obvious, dark spot. Basal portions of anal-fin rays outlined with small dark chromatophores. Caudal- fin rays outlined with small dark chromatophores, giving fin overall dusky appearance. Dense concentration of chromato- phores on basal portions of middle caudal-fin rays forming ir- regular spot variably continuous with midlateral stripe, spot particularly prominent in smaller individuals. Pectoral and pel- vic fins typically hyaline, sometimes with few scattered, dark chromatophores. ECOLOGY.—Stomach contents of specimens prepared for clearing and counter staining consisted solely of parts of larval insects. DISTRIBUTION.—Creagrutus atrisignum is apparently lim- ited to the Rio Maranhao basin, a tributary of the upper Rio To- cantins (Figure 22, triangles). REMARKS.—A portion of the paratype series of Creagrutus atrisignum is a lot of seven specimens (CAS 41340). One paratype is not Creagrutus but rather an individual of Brycon- americus or a similar genus. The type series and many of the other examined lots of Crea- grutus were collected by Carl Ternetz in the Rio Maranhao sys- tem, an upper tributary of the Rio Tocantins in the state of Goias, Brazil. Although it impossible to determine the exact lo- cation of many of the collecting sites report by Ternetz, the available information indicates that they all lie within the Rio Maranhao basin. MATERIAL EXAMINED.—130 specimens (30,37.2-55.2). BRAZIL. Goias: Rio Maranhao "into Rio Tocantins," upper Rio Tocantins basin, CAS 41339, 1 (46.0, holotype of Creagru- tus atrisignum, formerly IU 17679). Corrego do Monjolo, trib- utary of Rio Maranhao, CAS 69260, 7 (6,45.4-51.2, paratypes of Creagrutus atrisignum, formerly IU 17680, in part; see un- der "Remarks," above, concerning identity of other specimen in lot); MCZ 31571, 1 (47.5, paratype of Creagrutus atrisignum). Rio Arial-Velho "into Rio Maranhao" (approxi- mately 15°20'S, 47°58'W), CAS 69241, 1 (37.2). Rio Mara- nhao, at Aqua Quente, CAS 69504, 1 (42.5). Rio Bom-Jesus "into Rio Maranhao," CAS 69240, 3 ( 1 , 44.6). Salobro "Brook" (?=C6rrego Salobro, 15°13'S, 48°08'W), CAS 69260, 3 (50.5-55.2). Niquelandia, Rio do Peixe, right bank tributary of Rio Maranhao (14°28'S, 48°45'W), MNRJ 12662, 16 (14, 37.8-53.5), USNM 341516, 2 (41.4-49.8). Municipio de Niquelandia, Ribeirao do Engenho, along road from Niquelan- dia to Codemin, 29 km S of Codemin (14°25'S, 48°28'W), NUMBER 613 71 FIGURE 26.—Creagrutus atrisignum. MNRJ 12662, 52.7 mm SL; Brazil, Goias, Niquelandia, Rio Maranhao basin, Rio do Peixe (14°28'S, 48°45'W). MCP 15929, 54; USNM 341479, 3 (1 specimen cleared and counterstained for cartilage and bone). Municipio de Niquelan- dia, Rio Bacalhau, along road from Niquelandia and Colinas (14°32'S, 48°23'W), MCP 15944, 18. Municipio de Niquelan- dia, Corrego Fundo, along road from Niquelandia and Colinas (14°28'S, 48°18'W), MCP 15960, 20. Creagrutus barrigai, new species FIGURES 27, 28, TABLE 8 DIAGNOSIS.—The combination of the possession of premax- illary dentition arranged in the three components generalized for most of the species of Creagrutus and Piabina without a distinctly larger gap between the first and second teeth of the primary series, 2 or 3 maxillary teeth, 5 teeth on each dentary, 36 to 38 vertebrae, 13 to 15 branched anal-fin rays, 8 to 10 pre- dorsal scales, 4 scale rows between the lateral line and the dor- sal-fin origin, 6 to 8 gill rakers on the upper limb of the first gill arch, the well-developed third infraorbital contacting the hori- zontal limb of the preopercle, the postorbital head length (34.2%-40.9% of HL), the bony orbital diameter (36.2%- 42.0% of HL), the lack of a series of dark midlateral spots on the body, the vertically elongate humeral mark, and the later- ally compressed, relatively deep body distinguish C. barrigai from all congeners other than C. manu and C. pearsoni. Crea- grutus barrigai can be separated from C. manu by the distance from the snout to the anal-fin origin (58.5%-63.4% of SL ver- sus 63.5%-66.4% of SL, respectively) and the absence in C. barrigai of the dark midlateral stripe present in C. manu. Crea- grutus barrigai can, in turn, be discriminated from C. pearsoni by differences in the distance from the snout to the dorsal-fin origin (45.4%-49.2% of SL versus 49.4%-52.9% of SL, re- spectively), the anal-fin length (18.0%-20.7% of SL versus 15.6%-17.4% of SL, respectively), the postorbital head length (34.2%-40.9% of HL versus 41.0%-45.1% of HL, respec- tively), and the number of scale rows between the lateral line and dorsal-fin origin (4 versus 5 or 6, respectively). DESCRIPTION.—Morphometric and meristic data for Crea- grutus barrigai in Table 8. Head and body relatively com- pressed compared with other members of genus, degree of compression somewhat more pronounced in larger specimens. Body depth relatively greater than in most other Creagrutus species; greatest body depth at dorsal-fin origin at all sizes. Dorsal profile of head moderately convex from tip of snout to vertical through nostrils, nearly straight from that point to tip of supraoccipital spine. Dorsal profile of body very slightly con- vex predorsally, without distinct change in alignment relative to that of head. Predorsal surface of body with obtuse median ridge proximate to dorsal-fin origin. Ventral profile of head with obvious obtuse angle at anteroventral corner of dentary, very slightly convex from that angle to isthmus. Prepelvic pro- file of body convex; convexity more pronounced in larger indi- viduals. Prepelvic region obtusely flattened transversely, more obviously so in larger specimens. Head obtusely rounded in lateral view, relatively compressed in dorsal view. Upper jaw somewhat longer than, and over- hanging, lower jaw. Snout slightly fleshy anteromedially, with papillae scattered over anterior portions. Papillae common on lateral surface of upper jaw and on folds and plicae extending between outer and medial premaxillary teeth. Lower lip fleshy anteriorly with numerous papillae on dorsal surface and scat- tered papillae anteriorly and anteroventrally. Infraorbital series relatively well developed and nearly cov- ering cheek. Third infraorbital horizontally elongate, with ven- tral margin contacting horizontal limb of preopercle. Posterior margins of third through fifth infraorbitals nearly in contact with vertical limb of preopercle. Premaxillary dentition in three series: primary row curved, with 5 or 6 teeth without pronounced gap between first and sec- ond teeth, but with medial tooth separated from anterior tooth 72 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY TABLE 8.—Morphometrics and meristics of Creagrutus barrigai, new species: (A) holotype of C. barrigai. MEPN 4621; (B) paratypes of C. barrigai (n=32); and (C) all Ecuadorian and Peruvian samples of C. barrigai from which counts and measurements were taken (n=7; see comments under "Remarks," concerning samples of the species from western Brazil). Standard length is expressed in mm; measurements 1 to 14=percentages of stan- dard length; 15 to 18=percentages of head length. Characters Standard length 1. Snout to anal-fin origin 2. Snout to pelvic-fin insertion 3. Snout to pectoral-fin insertion 4. Snout to dorsal-fin origin 5. Dorsal-fin origin to hypural joint 6. Dorsal-fin origin to anal-fin origin 7. Dorsal-fin origin to pelvic-fin insertion 8. Dorsal-fin origin to pectoral-fin insertion 9. Caudal peduncle depth 10. Pectoral-fin length 11. Pelvic-fin length 12. Dorsal-fin length 13. Anal-fin length 14. Head length 15. Postorbital head length 16. Snout length 17. Bony orbital diameter 18. Interorbital width Lateral line scales Scale rows between dorsal-fin origin and lateral line Scale rows between anal-fin origin and lateral line Predorsal median scales Branched dorsal-fin rays Branched anal-fin rays Branched pelvic-fin rays Pectoral-fin rays Vertebrae A 46.9 59.1 45.8 23.7 46.3 56.9 35.4 31.8 35.0 11.5 19.6 16.0 24.7 18.5 24.5 39.1 24.3 40.0 32.2 39 4 3 10 8 15 6 12 38 B Morphometrics 19.1-46.5 58.5-63.3 45.2-48.9 22.9-25.3 45.4-49.0 54.4-59.4 32.6-39.3 29.1-36.4 33.5-37.5 11.0-12.9 18.6-21.5 14.2-17.5 24.4-27.0 18.0-20.7 24.4-26.4 34.2-39.9 23.6-28.2 36.2-41.7 31.6-34.6 Meristics 36-39 4 3 8-10 8 13-15 6 12-14 36-38 C 19.1-53.3 58.5-63.4 45.2-48.9 22.9-25.3 45.4-49.2 54.4-59.4 32.6-39.3 29.1-36.4 33.0-37.5 11.0-13.1 18.5-21.5 13.7-17.5 24.4-27.3 18.0-20.7 24.4-26.4 34.2^»0.9 23.3-28.2 36.2-42.0 30.9-34.6 36-39 4 3 8-10 8 13-15 6 12-14 36-38 of contralateral series by distinct gap; triangular cluster of 3 larger teeth; and single tooth of form similar to that of primary series occurring lateral to fourth tooth, or lateral to area of con- tact of third and fourth teeth of primary row. Maxilla with 3, rarely 2, tricuspidate teeth. Dentary with 5 tricuspidate teeth; first and second distinctly larger than remaining teeth; second tooth slightly larger than first and both of these teeth approxi- mately three times size of third tooth. Fourth and fifth teeth graded in size, more compressed than anterior teeth. Dorsal-fin rays ii,8 in all specimens. Dorsal-fin origin ap- proximately at vertical through pelvic-fin insertion. Profile of distal margin of dorsal fin moderately concave. Anal-fin rays ii,13—15 or iii,14-15; first anal-fin ray short when three rays present. Profile of distal margin of anal fin distinctly concave, anterior anal-fin rays forming distinct lobe. Mature males with hooks present on first, or first and second, branched anal-fin rays. Pectoral-fin rays i, 11-13. Tip of pectoral fin extending posteriorly slightly over three-fourths of distance to pelvic-fin insertion. Pelvic-fin rays i,6,i in all specimens. Tip of pelvic fin extending posteriorly to, or slightly beyond, anus. Mature males with hooks typically present on all branched pelvic-fin rays, or with hooks rarely absent on lateralmost branched ray. Gill rakers 6-8 + 9-13. COLORATION IN ALCOHOL.—Ground coloration tan. Dorsal surface of head with scattered, dark chromatophores slightly more concentrated on posterior portion of head and over snout. Deep-lying field of dark chromatophores overlying brain. Chromatophore field anterior to nostrils slightly more concen- trated, forming indistinct crescent. Ventral and dorsal margins of orbit outlined by variably obvious narrow band of dark chro- matophores. Scattered, dark chromatophores variably present posteriorly on dorsal portions of infraorbital series and proxi- mate region of lateral surface of head. Scales of dorsal portion of body with small dark chromato- phores concentrated along posterior scale margin. Deeper-lying series of chromatophores under scales aligned with series of chromatophores along margins of overlying scale, with two chromatophore fields together giving overall reticulate appear- ance to that portion of body. Scales of midlateral region of body with scattered chromatophores without definite pattern. Humeral mark somewhat indistinct. Anterior and posterior NUMBER 613 73 FIGURE 27.—Creagrutus barrigai, new species, holotype, MEPN 4621, 46.9 mm SL; Ecuador, Sucumbios, Rio Aguarico, near San Pablo de Kantesiya (0°I5'18"S, 76°25'30"W). FIGURE 28.—Map of central and northern South America showing geographic distribution of Creagrutus barri- gai (dots, 1 =type locality), Creagrutus beni (squares, 2=type locality), Creagrutus bolivari (stars, 3=type local- ity), and Creagrutus britskii (triangles, 4=type locality) (some symbols represent more than one locality or lot of specimens). 74 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY margins of mark ranging from straight to somewhat bowed both anteriorly and posteriorly. Dorsal region of humeral mark merging into chromatophore field of dorsal portion of body, with ventral portion of mark sometimes continued ventrally as variably developed field of scattered, dark chromatophores. Faint lateral stripe formed mostly of dark surface chromato- phores present approximately one scale dorsal of lateral line; stripe beginning slightly anterior of vertical through dorsal-fin origin and extending onto caudal peduncle. Dorsal fin with anterior unbranched ray and basal portions of second unbranched rays and anterior branched rays outlined with small, dark chromatophores. Membranes of distal two- thirds of dorsal fin with scattered, dark chromatophores. Anal- fin membranes with scattered chromatophores; chromato- phores less common on membranes of anterior and posterior rays. Caudal-fin rays with scattered chromatophores; chro- matophores typically most concentrated on basal portions of middle caudal-fin rays, giving dusky appearance to that region. Some individuals with faint horizontal stripe along middle cau- dal-fin rays. Pectoral and pelvic fins ranging from hyaline in smaller specimens to having scattered, dark chromatophores in larger individuals. ETYMOLOGY.—The species name, barrigai, is in honor of Ramiro Barriga of the Universidad Politecnica, Quito, Ecua- dor, in recognition of his many contributions to our knowledge of the freshwater fishes of Ecuador and of his assistance to the authors in this and other projects. ECOLOGY.—Two juvenile, nontype specimens collected in the Rio Aguarico basin along the Ecuador-Peru frontier (USNM 329815) came from a slow-moving, clear-water stream. Mature males, as indicated by the presence of well-de- veloped anal and pelvic-fin hooks, range from 32.1 to 41.2 mm SL, whereas females collected with those specimens reach no- tably larger sizes, 40.7-53.3 mm SL. Examination of the stomach contents of two specimens pre- pared for clearing and staining indicated that they fed exclu- sively on insects. DISTRIBUTION.—Creagrutus barrigai occurs in the western portions of the Amazon basin in northeastern Peru, northeast- ern Ecuador, and western Brazil (Figure 28, dots). GEOGRAPHIC VARIATION.—Creagrutus barrigai is known from scattered localities in the western portion of the Amazon basin. Most examined samples originated in the Rio Napo sys- tem, with the majority being from the Rio Aguarico basin of northeastern Ecuador. Distinctly separated from those collec- tions geographically are samples herein considered to be that species from the Rio Santiago system of northeastern Peru, the upper portions of the Rio Junta and Rio Purus in Acre, Brazil, and the Rio Javari in western Amazonas, Brazil (see, however, comments below concerning the Brazilian samples). No differ- ences were found between the population samples of C. barri- gai from various localities in Ecuador and Peru. One specimen in poor condition (NRM 16860) from the Rio Javari along the Brazilian-Peruvian frontier, and three speci- mens from the Rio Tarauaca in the upper portions of the Rio Jurua in Acre, Brazil, apparently represent a major range exten- sion to the southeast for C. barrigai beyond the core distribu- tion of the species in Ecuador and Peru. Although agreeing with the Peruvian and Ecuadorian samples of this species in pigmentation and the vast majority of meristic and morphomet- ric features, the limited Brazilian samples of C. barrigai for which radiographs are available, differ in having 36 or 37 ver- tebrae with 36 vertebrae most common (36, n=5; 37, n=2). Samples of the species from Peru and Ecuador, in contrast, have 36 to 38 vertebrae, but with a mode of 37 vertebrae (36, n=6; 37, n=82; 38, n=18). The proportional postorbital head length of these Brazilian samples (37.5%-42.9% of HL) also is at the upper range of this proportion for the species, and ex- tends slightly beyond the highest value for that feature in the Peruvian and Ecuadorian samples (34.2%-40.9% of HL). Ad- ditional samples from throughout the western portions of the Amazon are necessary to determine the significance, if any, of these differences. MATERIAL EXAMINED.—216 specimens (40,19.1-53.3). HOLOTYPE.—ECUADOR. Sucumbios: Rio Aguarico, near San Pablo de Kantesiya (0°15'18"S, 76°25'30"W), collected by D.J. Stewart et al., 23 Nov 1983, MEPN 4621, 1 (46.9). PARATYPES.—32 specimens (32, 19.1-46.5). ECUADOR. Sucumbios: Rio Aguarico, near San Pablo de Kantesiya (0°15'18"S, 76°25'30"W), collected with holotype, MEPN uncataloged, 10 (31.6-45.4); USNM 340977, 4 (33.6-46.4). Rio Aguarico, near Destacamento Militar Cuya- beno and mouth of Rio Cuyabeno in the Rio Aguarico (O°15'3O"S, 75°53'3O"W), collected by R. Barriga et al., MEPN 5252, 7 (19.1-34.7); USNM 340978, 3 (23.0-33.6). Rio Aguarico, near mouth of stream draining from Laguna Zan- cudo Cocha, upstream of Zancudo (0°33'S, 75°30'W), USNM 340976, 8 (40.3-46.5; 2 specimens cleared and counterstained for cartilage and bone). NONTYPE SPECIMENS.—183 specimens (7, 27.8-53.3). BRAZIL. Amazonas: Rio Javari basin, right bank sand playa immediately downstream of confluence of Rio Jaquirana and Rio Galvez (approximately 5°10'S, 72°53'W), NRM 16860, 1. Acre: Tarauaca, Rio Tarauaca (approximately 8°10'S, 70°40'W), MZUSP 30573, 4 (3, 33.7^8.8); MZUSP 30574, 30. Rio Acre between Seringal Paraiso and Lago Amapa, MZUSP 49761, 35. Rio Acre, Seringal Floresta, 10 minutes above Boca do Acre (latter at 8°45'S, 67°23'W), MZUSP un- cataloged ex. MZUSP 49600, 1. ECUADOR. Napo: Rio Napo near Pompeya (0°26'30"S, 76°28'12"W), MZUSP 38678, 10. Rio Jivino, lower 4 km to approximately 0.6 km upstream from mouth (between the two "ports" for Limonococha, FMNH 106030,43. PERU. Amazonas: Rio Santiago at La Poza (4°01'S, 77°47'W), LACM 39913-16, 49 (4, 27.8-53.3). Loreto: Pro- vincia Maynas, Puesto de Vigilancia Arcadia, Quebrada Isla, Rio Napo (approximately POO'S, 75°18'W), USNM 328575, 3. Rio Napo, mouth of Rio Mazan, INHS 36601, 7. NUMBER 613 75 Creagrutus beni Eigenmann, 1911 FIGURES 28, 29, TABLE 9 Creagrutus beni Eigenmann, 1911:172, pi. 6: fig. 2 [type locality: Villa Bella on Rio Beni (=Bolivia, El Beni, Rio Beni, Villa Bella); not specimen from Cachoeira de Velha de Rio Nova, Brazil, cited in footnote]; 1927:421, pi. 58: fig. 3, pi. 93: fig. 4 [Bolivia (El Beni), Rio Beni, Villa Bella; not remain- ing cited specimens or reported distribution of species in Colombia and Ven- ezuela; not pi. 93: figs. 5, 7].—Henn, 1928:63 [presence of holotype in Car- negie Museum].—Pearson, 1937b: 108 [Bolivia, Rio Beni and Mamore basins; not cited occurrence of species in Amazon basin outside Rio Beni system or citation of species in Rio Magdalena, Colombia].—Eigenmann and Allen, 1942:228 [Bolivia, Rio Beni; not listed specimens or cited distri- bution of species outside of Rio Beni basin],—Fowler, 1945a: 148 [literature compilation; not citations for Rio Marafion, Peru, or cited distribution out- side Bolivia]; 1948:83, fig. 88 [literature compilation; not citations of occur- rence of species outside Bolivia]; 1975:26 [listing],—Gery, 1964:60 [in key, not cited occurrence of species in Peru, [Rio] Meta of Columbia, and Vene- zuela],—Terrazas-Urquidi, 1970:25 [listing in fishes of Bolivia].—Lau- zanne and Loubens, 1985:110 [Bolivia: Rio Mamore basin].—Ibarra and Stewart, 1987:28 [holotype depository] —Lauzanne etal., 1991:66 [Bolivia: Rio Chapare and Rio Boopi].—Not Eigenmann, 1920:12; 1921, pi. 93: fig. 7; 1922:238.—Not Pearse, 1920:12, 25, 43—Not Fowler, 1931:408; 1942:134; 1943a:238; 1945b: 102.—Not Pearson, 1937a:92—Not Beebe, 1945:84; 1948:149— Not Pozzi, 1945:270.—Not Femandez-Yepez, 1952: 43.—Not Luengo, 1963:326.—Not Mago-Leccia, 1967:233; 1970:70.—Not Gery, 1972.66.—Not Saul, 1975:106—Not Cala, 1977:7.—Not Ortega and Vari, 1986:8—Not Stewart etal., 1987:26— Not Marrero and Machado-Al- lison, 1990:66—Not Barriga, 1991:17.—Not Lowe-McConnell, 1991: 68.—Not Pavlov et al., 1995:233. DIAGNOSIS.—The combination of the possession of premax- illary dentition arranged in the three components generalized for most of the species of Creagrutus and Piabina without a distinctly larger gap between the first and second teeth of the primary series, 6 (rarely 5) teeth in the primary tooth row of the premaxilla, 2 to 4 teeth on each maxilla, 6 teeth on each dentary, 38 to 42 lateral line scales without a lamellar process over each pore, 9 to 12 median predorsal scales, 3 or 4 rows of scales between the lateral line and the anal-fin origin, 2 post- anal scales to the anal-fin origin, 9 to 11 branched anal-fin rays, 6 or 7 gill rakers on the upper limb of the first gill arch, 8 to 10 gill rakers on the lower limb of the first gill arch, the dis- tance from the snout to the pelvic-fin insertion (44.0%-47.8% of SL), the postorbital head length (44.6%-50.1% of HL), the bony orbital diameter (29.5%-32.7% of HL), the snout length (22.6%-28.9% of HL), the interorbital width (29.7%-32.7% of HL), the caudal peduncle depth (11.4%-12.9% of SL), the well-developed third infraorbital whose ventral margin ap- proaches or contacts the horizontal limb of the preopercle, the lack of a series of dark spots along the midlateral surface of the body, the discrete, vertically elongate humeral mark, and the lack of a distinct patch of dark pigmentation on the middle por- tions of the anterior dorsal-fin rays distinguishes Creagrutus beni from all congeners with the exception of C. changae. Those two species can be discriminated by the number of den- tary teeth (6 on each dentary in C. beni versus 5 in C. changae) and by differences in the bony orbital diameter (7. l%-8.4% of TABLE 9.—Morphometrics and meristics of Creagrutus beni: (A) holotype of C. beni, FMNH 54585, formerly CM 3216 (specimen apparently dried out at some point and in poor condition, thus morphometric values not directly com- parable to those of other specimens. See also "Remarks'" under species descrip- tion concerning differences between several characters in the holotype and information on those features presented in original description of the species); and (B) all other specimens of C. beni from which counts and measurements were taken (n=60). Standard length is expressed in mm; measurements 1 to 14 =percentages of standard length; 15 to 18=percentages of head length. Dashes indicate values for holotype that could not be accurately determined as a conse- quence of the poor condition of the specimen. Characters Standard length 1. Snout to anal-fin origin 2. Snout to pelvic-fin insertion 3. Snout to pectoral-fin insertion 4. Snout to dorsal-fin origin 5. Dorsal-fin origin to hypural joint 6. Dorsal-fin origin to anal-fin origin 7. Dorsal-fin origin to pelvic-fin insertion 8. Dorsal-fin origin to pectoral-fin insertion 9. Caudal peduncle depth 10. Pectoral-fin length 11. Pelvic-fin length 12. Dorsal-fin length 13. Anal-fin length 14. Head length 15. Postorbital head length 16. Snout length 17. Bony orbital diameter 18. Interorbital width Lateral line scales Scale rows between dorsal-fin origin and lateral line Scale rows between anal-fin origin and lateral line Predorsal median scales Branched dorsal-fin rays Branched anal-fin rays Branched pelvic-fin rays Pectoral-fin rays Vertebrae A B Morphometrics 40.4 61.0 44.1 21.3 46.7 58.3 34.5 30.0 31.9 11.9 - - - - 24.3 42.9 26.5 36.7 33.7 33.6-73.3 59.8-66.2 44.0-47.8 21.2-26.0 46.6-50.7 53.9-59.4 29.9-34.7 27.1-30.7 32.0-35.9 11.4-12.9 18.4-22.1 13.9-16.8 20.1-25.1 16.8-20.1 24.7-27.2 44.6-50.1 22.6-28.9 29.5-32.7 29.7-32.7 Meristics 39 4 3 8^ 8 11 - - 38 38-42 4-5 • 3-4 9-12 8 9-11 5-7- 12-14 37-39 'Five scale rows between dorsal-fin origin and lateral line typical, 4 scales less common. 2Five branched pelvic-fin rays present in only one specimen. SL, less than horizontal distance from posterior margin of orbit to posterior margin of opercle in C. beni versus 8.7%-10.3% of SL, equaling or exceeding horizontal distance from poste- rior margin of orbit to posterior margin of opercle in C. chan- gae). DESCRIPTION.—Morphometric and meristic data for Crea- grutus beni in Table 9. Head relatively robust in all specimens larger than 25 mm SL, body more robust anteriorly, more so in specimens larger than 30 mm SL. Greatest body depth at dor- sal-fin origin in smaller specimens, shifted slightly anteriorly in some larger individuals. Dorsal profile of head smoothly con- vex from tip of snout to vertical through center of orbit in all specimens, profile from that point to rear of supraoccipital 76 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY spine ranging from slightly convex to slightly concave. Predor- sal profile continuous with that of head in smaller individuals, with variably evident change in alignment relative to that of head in larger specimens. Ventral profile of head ranging from smoothly convex to having variably obvious obtuse angle at anteroventral corner of dentary, angle typically more obvious in larger individuals. Ventral profile of body smoothly convex from isthmus to anal-fin origin, convexity usually more pro- nounced in larger individuals. Head obtusely pointed in lateral view, but more compressed laterally from dorsal view. Upper jaw distinctly longer than, and overhanging, lower jaw. Anterior portion of snout some- what fleshy, with numerous small papillae. Papillae more con- centrated on fleshy upper lip, fleshy folds, and plicae extending between outer and medial premaxillary teeth, and on lateral surface of maxillae. Papillae also common in many specimens on dorsal margin of lower lip, with scattered papillae over ven- tral surface of lip. Infraorbital series moderately developed. Third infraorbital variably developed, with ventral margin contacting, or nearly contacting, ventral limb of preopercle in some individuals, but falling short of that point in other specimens. Posterior margins of third through fifth infraorbitals falling distinctly short of ver- tical limb of preopercle (see under "Remarks," below, concern- ing discrepancy in this feature between data in original species description and condition in putative holotype). Premaxillary dentition in three series: primary row moder- ately curved, more so anteriorly, typically consisting of 6 teeth, with approximately 5% of specimens with only 5 teeth in se- ries, without pronounced gap between first and second tooth of series but with medial tooth of series distinctly separated from matching tooth of contralateral series; triangular cluster of 3 teeth with posterolateral tooth somewhat larger and with me- dial teeth on contralateral clusters in contact; and single tooth of form similar to that of primary series lying lateral to fourth tooth of primary premaxillary series or lateral to space between third and fourth tooth of that series. Maxilla with 2 to 4, typi- cally 3, teeth, teeth all tricuspidate or fourth tooth, when present, sometimes with straight distal margin. Dentary with 6 teeth; 3 anterior teeth distinctly larger and tricuspidate with middle cusp larger, middle cusp of third tooth posteriorly re- curved; first and second teeth largest and subequal, larger than third; fourth to sixth teeth graded in size, tricuspidate or last tooth sometimes conical. Dorsal-fin rays typically ii,8, iii,8 in one examined specimen with very short first unbranched ray. Dorsal-fin origin slightly posterior of vertical thorough pelvic-fin insertion. Profile of distal margin of dorsal fin straight in smaller specimens, be- coming convex in larger individuals, with slight indication of anterior lobe. Anal-fin rays ii,9-ll. Profile of distal margin of anal fin distinctly concave, with slightly developed anterior lobe. Mature males with hooks on last unbranched and anterior 3 to 6 branched anal-fin rays. Pectoral-fin rays i,l 1-13. Pecto- ral fin extending posteriorly somewhat more than three-fourths of distance to pelvic-fin insertion. Pelvic-fin rays typically i,6,i; i,7 in approximately 15% of specimens, i,5,i in one individual. Mature males with pelvic-fin hooks present on all branched rays of some specimens and also on medial unbranched ray in one specimen. Tip of pelvic fin extending to anus. Gill rakers 6-7 + 8-10. COLORATION IN ALCOHOL.—Specimens retaining guanine on scales silvery, more so in region overlying midlateral body stripe and over lateral surface of head. Dorsal surface of head with field of small, dark chromatophores, more so posteriorly. Chromatophore field continuing anteriorly, but less concen- trated over snout and upper lip. Region immediately anterior to nares with dark chromatophores somewhat more concentrated; chromatophore field in that region continuous with curved band of chromatophores ventral and posterior to orbit. Dorsal portions of infraorbital series and opercle with scattered, large, dark chromatophores. Scales of dorsal portion of body with small, dark chromato- phores concentrated over anterior portion of exposed section of scales and with band of dark chromatophores along posterior margin of scales. Two pigmented regions separated by hyaline crescent. Humeral mark well developed in all specimens larger than 25 mm SL, variably masked in specimens retaining gua- nine on scales; vertically elongate with slightly irregular bor- ders, vertical extent of humeral mark greater in larger individu- als. Intensity of pigmentation usually even across humeral mark, slightly less developed dorsally and ventrally in some in- dividuals. Obscure midlateral body stripe formed by deep-lying and surface chromatophores extending from under dorsal fin to rear of caudal peduncle. Stripe vertically expanded on caudal peduncle, but not extending onto caudal-fin base. Dorsal fin with margins of rays and membranes overlain with small dark chromatophores on distal two-thirds of fin; pigmentation most developed on anterior one-half of fin. Anal fin with anterior margins of rays outlined by series of small dark chromatophores, anterior rays with chromatophores ex- tending over basal two-thirds of rays; extent of chromatophore series along rays becoming progressively reduced posteriorly. Anal-fin ray membranes with scattered, dark chromatophores, more so in larger individuals. Caudal-fin rays outlined by series of dark chromatophores. Pelvic and pectoral fins hyaline or with scattered, dark chromatophores. ECOLOGY.—Little information is available about the ecology of Creagrutus beni, but examined specimens come from a noteworthy range of elevations. The type locality (Villa Bella on the Rio Beni) and other sites from which population sam- ples are available, are at less than 200 m elevations, whereas some lots from the Department of Cochabamba and La Paz originated at sites of above 1000 m elevation. A 55.0 mm SL female from the Rio Mamore (MCNG 23913) was filled with numerous eggs. Mature males, as evidence by hooks on the anal and pelvic fins, are typically smaller than si- multaneously collected, larger, presumably female, specimens. NUMBER 613 77 FIGURE 29.—Creagrutus beni, USNM 340959, 48.0 mm SL; Bolivia, Cochabamba, Rio Chapare basin. Villa Tunari(16°55'S, 65°22'W). DISTRIBUTION.—Creagrutus beni is endemic to the upper portions of the Rio Madeira system in northeastern Bolivia (Figure 28, squares). REMARKS.—Eigenmann's original description (1911:172) of Creagrutus beni was based on a single specimen described as being "53 mm" and as having the "second suborbital [=third infraorbital] in contact with the preopercle below, but not be- hind." The specimen, now cataloged as the holotype (FMNH 54585, formerly CM 3216), does not match the original de- scription in either of these details. Evaluation of the differences between the details in the original species description and the purported holotype is complicated by the fact that the specimen is extremely stiff with sunken eyes and body, indicating that it was desiccated at some point. The specimen, furthermore, lacks the left maxilla, has a badly damaged lower jaw, and has lost most of its fin rays. The specimen identified as the holotype of C. beni is approx- imately 40.4 mm SL, contrary to the 53 mm cited by Eigen- mann (1911) who failed, however, to specify whether he was reporting standard or total length. Both standard and total lengths were utilized by Eigenmann in some of his publications (e.g., Eigenmann and Ogle, 1907), but he more typically cited total rather than standard length (e.g., holotype of Stethaprion crenatus cited by Eigenmann (1916:80) as being 96 mm, whereas Reis (1989:57) reported it as 76.7 mm SL, and holo- type of Acestrorhynchus nasutus Eigenmann (1912:411) cited by that author as being 79 mm, whereas Menezes (1969:120) reported it as 66 mm SL). Based on the proportion of standard versus total length apparent in the figure accompanying the original description of C. beni and subsequently reproduced by Eigenmann (1927, pi. 58: fig. 3), the standard length of the specimen would be about 44 mm, approximately 10% longer than that of the putative holotype. It is impossible to determine the degree to which the difference between this estimated stan- dard length for the holotype and the actual standard length of the specimen cited as the holotype might be explained by the desiccation that the specimen experienced at some point. More problematic than the possible discrepancy in standard length are the differences between the degree of development of the third infraorbital reported in the original description by Eigenmann (1911) and that occurring in the putative holotype of C. beni. The third infraorbital in the putative holotype is continuously in contact along both its ventral and posterior margins, respectively, with the horizontal and vertical limbs of the preopercle. In contrast, Eigenmann (1911:172) describes the third infraorbital (the "second suborbital" under the termi- nology utilized by Eigenmann) as not in contact with the preo- percle "behind" [=posteriorly]. Again, it is uncertain whether the pronounced dissection that the specimen experienced at some point accounts for the discrepancy between the original description and the condition in the putative holotype. Only two species of Creagrutus are known from the region of the type locality of C. beni. The first of these is Creagrutus pearsoni (=Piabina beni of authors prior to Mahnert and Gery (1988:5)), originally described from the Rio Beni basin in the upper portion of the Rio Madeira system. Creagrutus pearsoni differs in numerous features from the values reported by Eigen- mann (1911) for C. beni, most notably in the number of branched anal-fin rays and in overall body form (see Table 44 and compare Figures 29 and 76), and indeed was removed by Pearson (1924) to another genus. The second Creagrutus spe- cies represented in available material from the Bolivian portion of the upper Rio Madeira matches the original description of C. beni in both the number of branched anal-fin rays and overall body form. All of the specimens of this Creagrutus species, however, lack any contact between the posterior margin of the third infraorbital and the vertical limb of the preopercle con- trary to the situation in the specimen identified as the holotype of C. beni in which such contact occurs. These population sam- ples also demonstrate variation as to extent to which the ventral margin of the third infraorbital approaches the horizontal limb of the preopercle. These differences raise questions as to whether the specimen now identified as the holotype of Crea- grutus beni is the individual described by Eigenmann (1911). It 78 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY is, nonetheless, possible that these discrepancies may be a con- sequence of the desiccation that the specimen underwent at some point in the past. Although we are unable to resolve these discrepancies at this time, the information in the original description of Creagrutus beni is mostly congruent with range of values found in this sec- ond of the two Creagrutus species known from the type region of C. beni. The name is applied herein to that form that served as the basis for the redescription of the species in this paper. Subsequent to its description by Eigenmann (1911) from northeastern Bolivia, Creagrutus beni has been reported from a broad range of localities throughout South America extending north along the eastern slope of the Andean Cordilleras (Eigen- mann, 1927:421; Pearson, 1937a:92; Saul, 1975:106) into the Rio Orinoco basin (Eigenmann, 1912:12, 1922: 238, 1927:422; Pearse, 1920:12; Fowler, 1943a:238) as far east as the mouth of that river system (Fowler, 1931:408). Creagrutus beni has also been reported from Argentina (Pozzi, 1945:270; Ringuelet and Aramburu, 1961:30; Ringuelet et al., 1967:134), the western slope of the Andes (Eigenmann, 1927:421), the rivers draining into Lago Maracaibo of northwestern Venezuela (Schultz, 1944:336), coastal rivers of the Caribbean versant of northern Venezuela (Schultz, 1944:336; Fernandez-Yepez, 1952:43; 1972, fig. 1), and the Rio Tocantins system of eastern Brazil (Eigenmann, 1911:172; 1927:43). Cala (1990:92), however, questioned this broad distribution, proposing rather that C. beni probably forms a "complex" requiring a revisionary study. The known distribution of C. beni is in actuality significantly more restricted than indicated in the literature, encompassing only the upper portion of the Rio Madeira system in eastern Bolivia. Reports of Creagrutus beni from the Rio Tocantins were based on material of C. atrisignum (footnote by G.S. My- ers in Eigenmann, 1927:421; Myers, 1927:116). Material re- ported as C. beni from the eastern slopes of the Andes in Peru (Pearson, 1937a:92; Fowler, 1945a: 148) is rather C. holmi (see "Remarks" under that species), and specimens cited as C. beni from eastern Ecuador (Saul, 1975:106) are C. flavescens (see "Remarks" under that species). Citations of C. beni from the Lago Maracaibo basin (Schultz, 1944:336) were based on sam- ples of forms that were later described as C. paralacus Harold and Vari (1994:14), those from the Rio Orinoco basin on sam- ples of C. melasma Vari et al. (1994:90), C. hysginus Harold et al. (1994:975), C. bolivari (see "Remarks" under that species), and C. taphorni (see "Remarks" under that species). Citations of C. beni from the Caribbean versant of Venezuela were based on specimens of C. lassoi (see "Remarks" under that species), C. lepidus Vari et al. (1993:354), and C. taphorni (see "Re- marks" under that species). The report of C. beni from the provinces of Jujuy and Salta in Argentina by Pozzi (1945:270) was later reiterated by Ringue- let and Aramburu (1961:30) and Ringuelet et al. (1967:134), evidently without the examination of additional specimens. These reports represent either a major range extension for the genus, perhaps being of one of the species of the two other spe- cies of the genus endemic to the Rio de La Plata basin, or a mis- identification at the generic level. Our examinations of speci- mens indicate that the Argentinean provinces of Jujuy and Salta lie outside the known range of Creagrutus. In addition, numerous other authors have reported Creagru- tus beni from portions of South America beyond the known range of the species as confirmed by specimens examined for this study (see listing of authors at the end of the synonymy for C. beni). In light of the extralimital origin of these specimens, these citations are judged to be misidentifications of C. beni. The absence, or unavailability, of voucher specimens associ- ated with many of these citations makes it impossible to deter- mine the identity of this material. Mahnert and Gery (1988:5) synonymized Piabina Reinhardt (1867) into Creagrutus Giinther (1864), an action that made Pi- abina beni Pearson (1924) a secondary homonym of Creagru- tus beni Eigenmann (1911). Mahnert and Gery consequently proposed pearsoni as a replacement name for beni Pearson within Creagrutus. MATERIAL EXAMINED.—161 specimens (60, 33.6-73.3). BOLIVIA. El Beni: Villa Bella (10°23'S, 65°24'W), FMNH 54585, 1 (40.4, holotype of Creagrutus beni; formerly CM 3216). Rio Mamore, Laguna de Cristal Mayo (not located), MCNG 23913, 1 (55.0). Provincia Ballivian, Territorio Indi- gena Reserva de la Biosfera Pilon-Lajas, mouth of Rio Suapi (approximately 14°47'S, 67°38'W), 20 (15,44.5-73.3). Provin- cia Ballivian, Rio San Bernardo, at road from Yucumo to Rur- renbaque (approximately 13°38'S, 65°23'W), CBF 2366, 15 (9, 45.3-68.5). Provincia Cervado, Rio Ibare, 5 km N of Puerto Almacen (latter locality at 14°53'S, 64°57'W), UF 82519, 1. Ox-bow lagoon approximately 96 m from Rio Itenez, 9 km S of Costa Marques, Brazil (12°32'24"S, 64°12'42"W), UMMZ 204418, 5. Rio Mamore, Isla Nicolas Suarez, between Gua- yaramerin, Bolivia, and Guajara Mirim, Brazil (approximately 10°48'S, 65°23'W), AMNH 40189, 20. Cochabamba: Rio Chapare basin, Villa Tunari (16°55'S, 65°22'W), MNHN 1989- 1473,5 (39.5-58.6); USNM 340959, 11 (6, 35.2^*8.0; 2 speci- mens cleared and counterstained for cartilage and bone); MZUSP 27808, 5 (40.6-52.1); CBF 82, 3 (2, 51.3-55.1). Villa Tunari, Rio Juntas de Caroni (approximately 16°55'S, 65°22'W), MCNG 23912, 3. Confluence of Rio Chapare and Rio Coni (approximately 16°51'S, 65°08'W), MHNG 2227.69, 1 (59.7). La Paz: Provincia Sud Yungas, upper Rio Beni, at San Miguel de Huachi (15°40'S, 67°15'W), MHNG 2227.68, 1 (38.0). Provincia Sud Yungas, upper Rio Beni, Rio Boopi, San Miguel de Huachi (15°40'S, 67°15'W), CBF 59, 2 (60.4-67.9). Rio Iniqui, tributary of Rio Beni, approximately one-half dis- tance between Huachi (?=San Miguel de Huachi) and Rurren- baque, CAS 69287, 19 (5, 52.0-67.0). Provincia Iturralde, un- named arroyo, 14 km W of Ixiamas (latter at 13°45'S, 68°09'W), CBF 02364, 3. Provincia Iturralde, Rio Yariapu sys- tem of Rio Beni basin, unnamed arroyo, 4 km S de Tumupasa (latter at 14°09'S, 67°55'W), CBF 2365, 6. Provincia Iturralde, Tumupasa (14°09'S, 67°55 'W), USNM 86802, 15 (5, NUMBER 613 79 45.0-54.8; formerly IU 17310, in part). Rio Iniqui, upper Rio Beni system, USNM 86840, 5 (formerly IU 17313, in part). Provincia Nor Yungas, Rio San Miguel, upper Rio Beni basin, Tomachi (15°26'S, 67°45'W), CBF 02361, 5. Rio Popoi, upper Rio Beni system, USNM 86771, 5 (2, 33.6-42.3; formerly IU 17311, in part). Rio Colorado, lower Rio Bopi system, USNM 86839, 5. Rio Coroico, Caranavi, INHS 36969, 4. Creagrutus bolivari Schultz, 1944 FIGURES 28, 30, TABLE 10 Creagrutus beni [not of Eigenmann, 1911].—Eigenmann, 1922:238 [Colom- bia: Rio Guadngua, Rio Roncador]; 1927:421 [in part, specimens from Co- lombia: Rio Guadrigua, Rio Roncador and perhaps Quebrada Cramalote, Vil- lavicencio], pi. 93: fig. 7 [illustrated specimen C. bolivari, not C. beni]. Creagrutus bolivari Schultz, 1944:334, fig. 49, tabs. 22, 23 [type locality: Ven- ezuela, Estado de Aragua, Rio Guarico and tributaries between San Sebastian and San Casimiro].—Myers and Roberts, 1967:249 [C. bolivari as a possible synonymy of C. phasma Myers, 1927].—Mago-Leccia, 1970:70 [footnote; C. bolivari as a possible synonym of C. phasma, following Myers and Rob- erts, 1967].—Fowler, 1975:26 [in list of nominal Creagrutus species].—Gery and Renno, 1989:3 [as a possible synonym of C. phasma].—Van and Howe, 1991:15 [location of type specimens].—Taphorn, 1992:170, figs. 40a, 109, 110 [occurrence in Rio Apure system, Venezuela; ecology, common name]. —Machado-Allison and Moreno, 1993:85-94, tabs. 1, 2, 5, 7 [ecology and distribution in Venezuela, Estado Guarico, Rio Orituco].—Machado-Al- lison et al., 1993:66, 69 [Venezuela, Rios Aguaro and Guariquito; ecolo- gy].—Machado-Allison et al., 1993:133 [Venezuela: low Llanos of Rio Orinoco basin].—Taphorn et al., 1997:71 [cited for Venezuela].—Marrero et al., 1997:76 [rivers of Llanos of Venezuela]. DIAGNOSIS.—The combination of the possession of premax- illary dentition arranged in the three components generalized for most of the species of Creagrutus and Piabina without a distinctly larger gap between the first and second teeth of the primary series, 2 to 4 teeth on the maxilla, 6, rarely 5, teeth in the primary tooth row of the premaxilla, 5 dentary teeth, 37 to 40 lateral line scales without a lamellar process over each pore, 8 to 10 predorsal scales, 4 scale rows between the dorsal-fin or- igin and the lateral line, 35 to 37 vertebrae, 8 to 10 branched anal-fin rays, 2 post-anal median scales to the anal-fin origin, the dis tance from the snout to the dorsal-fin origin (45.0%-50.3% of SL), the bony orbital diameter (28.2%- 36.6% of HL), the interorbital width (28.0%-33.3% of HL), the 5 to 9 gill rakers on the upper limb and 9 to 12 gill rakers on the lower limb of the first arch, the moderately developed third in- fraorbital whose ventral margin falls distinctly short of hori- zontal limb of preopercle, the lack of a series of dark midlateral spots on the body, the humeral mark in the form of a vertically elongate bar of nearly uniform width, and the absence of a dis- crete patch of dark pigmentation on the middle portion of the anterior dorsal-fin rays distinguishes Creagrutus bolivari within the clade composed of Creagrutus and Piabina. DESCRIPTION.—Morphometric and meristic data for Crea- grutus bolivari in Table 10. Body relatively deep and com- pressed. Greatest body depth at, or immediately anterior of, dorsal-fin origin. Dorsal profile of head distinctly convex from margin of upper lip to vertical through posterior margin of pos- terior nares, straight from that point to posterior tip of supraoc- cipital spine. Dorsal profile of body slightly and symmetrically convex to dorsal-fin origin, straight to slightly concave from that point to base of adipose fin, slightly concave from rear of adipose-fin base to caudal-fin base. Ventral profile of head with obtuse angle approximately midway between margin of lower lip and posterior of dentary, straight to slightly convex from that angle approximately to pectoral-fin insertion; slightly con- vex between pectoral- and pelvic-fin insertions; slightly con- cave from anal-fin origin to caudal peduncle. Upper jaw longer than, and overhanging, lower jaw. Anterior portion of snout quite fleshy, with many minute papillae on an- teromedial portion of snout, papillae continuing ventrally onto upper lip and into mouth on fleshy flaps between premaxillary teeth. Lower lip distinctly fleshy anteriorly, with papillae con- centrated on lip and decreasing in number ventrally and later- ally; papillae also present on isthmus. Infraorbital series relatively poorly developed, with ventral margin of third infraorbital distinctly separated from horizontal and vertical limbs of preopercle, gap between posterior margin of third infraorbital and vertical limb of preopercle at most one- third width of orbit; posterior and ventral margins of third in- fraorbital distinctly and smoothly curved. Posterior margins of fourth and fifth infraorbitals vertical and distinctly separated from vertical limb of preopercle by broad gap equal to approxi- mately one-half of width of fourth infraorbital. Premaxillary dentition in three series: primary row slightly curved, without pronounced gap between first and second tooth of series, typically with 6 teeth, although rarely 5 teeth, present on one premaxilla, and 7 teeth present on both premaxillae in one specimen; triangular cluster of 3 larger teeth with postero- medial tooth distinctly larger; and single tooth of form similar to that of primary series typically lying lateral to fourth tooth of primary row, or lateral to region where fourth and fifth teeth of that row contact. Maxilla with 2 to 4 tricuspidate teeth. Dentary with 5 tricuspidate teeth; second largest, about one and one- half times size of first tooth and twice height of third tooth but much more massive. Fourth and fifth dentary teeth distinctly smaller than third tooth in series. Dorsal-fin rays ii,8. Dorsal-fin origin located anterior of ver- tical through pelvic-fin insertion by distance equal to width of one or two midlateral scale rows. Distal margin of dorsal fin slightly concave, with slightly elongate anterior lobe. Anal-fin rays ii,8—10 or iii,8—10. Anal fin with hooks, when present, on segments of first branched ray of mature males (first two rays in 1 out of 5 hook-bearing specimens). Distal margin of anal fin slightly to markedly sinusoidal, with elongate anterior lobe fol- lowed by concavity. Pectoral-fin rays i,10-12. Pectoral fin rela- tively short, tip not extending to pelvic-fin insertion. Pelvic-fin rays i,6,i or i,7. Tip of pelvic fin approaching or extending to anteriormost unbranched anal-fin ray. Mature males with pel- vic-fin hooks on segmented and unsegmented portions of all 7 80 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY TABLE 10.—Morphometrics and meristics of Creagrutus bolivari: (A) holotype of C. bolivari. USNM 121497; (B) paratypes of C. bolivari, USNM 121498 (n=9); (C) nontype specimens of C. bolivari from the central por- tions of Orinoco basin in Venezuela (n= 17); and (D) nontype specimens of C. bolivari from the western portions of the Orinoco basin in Colombia (n=37) from which measurements were taken. Standard length is expressed in mm; measurements 1 to 14=proportions of standard length; IS to 18= proportions of head length. Characters Standard length 1. Snout to anal-fin origin 2. Snout to pelvic-fm origin 3. Snout to pectoral-fin origin 4. Snout to dorsal-fin origin 5. Dorsal-fin origin to hypural joint 6. Dorsal-fin origin to anal-fin origin 7. Dorsal-fin origin to pelvic-fin origin 8. Dorsal-fin origin to pectoral-fin origin 9. Caudal peduncle depth 10. Pectoral-fin length 11. Pelvic-fin length 12. Dorsal-fin length 13. Anal-fin length 14. Head length 15. Postorbital head length 16. Snout length 17. Bony orbital diameter 18. Interorbital width Lateral line scales Scale rows between dorsal-fm origin and lateral line Scale rows between anal-fin origin and lateral line Predorsal median scales Branched dorsal-fin rays Branched anal-fin rays Branched pelvic-fin rays Pectoral-fin rays Vertebrae A 50.2 2.7 47.0 25.1 48.2 56.2 32.9 30.1 34.3 12.4 20.3 17.3 16.9 18.1 26.5 45.9 28.6 33.1 32.3 38 4 3 8 8 9 7 13 37 B C Morphometrics 35.7^8.3 61.3-66.1 45.7-50.4 24.4-26.8 45.0-48.6 55.1-57.4 30.4-33.3 24.6-28.6 29.9-33.7 11.1-12.3 18.8-20.6 14.6-16.8 20.0-23.8 16.5-20.1 25.1-26.8 42.1^7.7 23.1-31.1 32.2-36.4 30.7-33.1 37.8-52.3 63.4-70.0 47.4-52.4 25.1-28.6 47.1-50.9 55.5-60.3 29.4-39.5 24.2-34.6 31.8-37.6 10.9-13.2 17.8-22.4 14.6-17.9 19.9-24.0 16.6-20.3 25.9-29.4 43.3^*9.5 27.2-32.2 28.2-36.6 28.0-32.4 Meristics 37^*0 4 3 8-9 8 8-10 6-7» 11-13 35-37 38-40 4 3 8-9 8 8-10 7 11-13 35-37 D 26.3-61.0 62.0-66.7 45.8-50.6 23.7-26.0 46.4-50.3 55.1-60.3 30.6-36.4 26.6-34.5 32.0-35.3 11.7-12.7 18.5-21.3 15.0-17.7 20.7-23.5 16.0-19.7 24.9-27.4 41.4-47.8 24.3-30.6 29.9-35.5 28.6-33.3 37-40 4 3 8-10 8 8-10 6-7' 11-13 36-38 'Medialmost pelvic-fin ray unbranched in some specimens. branched rays or 6 branched rays and on medial unbranched ray. Gill rakers 5-9 + 9-12. COLORATION IN ALCOHOL.—Dorsal surface of head with uniform diffuse pattern of small, dark chromatophores, larger and darker chromatophores present on lateral portions of fron- tals and on dorsal surface of brain. Smaller dark chromato- phores continuing anteriorly onto snout. Distinct small crescent of dark chromatophores immediately in front of anterior nares. Band of scattered, dark chromatophores extending from poste- rior wall of nares around ventral and posterior margin of orbit, and forming dense patch located anteroventral to eye. Pigmen- tation on ventral surface of head restricted to transverse band of small, dark chromatophores on lower lip. Pigmentation on lat- eral surface of head confined to widely scattered, large, light to dark brown chromatophores on dorsalmost portion of cheek and area covering upper portions of infraorbital series and opercle. Body with pigmentation most concentrated dorsally, particularly at dorsal-fin base and in narrow middorsal band extending from dorsal-fin base to procurrent caudal-fin rays, and over center of exposed surface of scales on dorsolateral surface of body. Humeral mark in form of vertically elongate bar of approximately uniform width with one-fourth of its length ventral of lateral line and remainder dorsal of that struc- ture. Pigmentation in mark most concentrated immediately dor- sal of lateral line. Overall form of humeral mark relatively straight ventrally and extending towards center of pectoral-fin base; dorsal portion of mark with distinctive anterior concavity and extending towards third or fourth predorsal scale. Humeral bar diffuse in smaller specimens, becoming vertically elongate between 23 and 27 mm SL. Little or no dark pigmentation on body ventral to lateral line. Some individuals with small, dark chromatophores delineating myosepta in region immediately dorsal to anal fin. Variably distinct predorsal stripe present; stripe formed by deep-lying, stellate, dark chromatophores. Chromatophores most concentrated anteriorly near supraoccip- ital spine in some specimens. Midlateral stripe located entirely NUMBER 613 81 FIGURE 30.—Creagrutus bolivah, paratype, USNM 121498, 42.3 mm SL; Venezuela, Aragua, Rio Guarico and tributaries between San Sebastion and San Casimiro (latter locality at lCOOTM, 67°01'W). above lateral line except on caudal peduncle, becoming denser posteriorly and expanding slightly over hypurals. Caudal-fin membranes invested with dark pigmentation de- lineating rays, pigmentation darkest on ventral lobe and espe- cially concentrated on central fin-rays; entire distal margin of caudal fin with a band of small, dark chromatophores. Un- branched anal-fin rays unpigmented, anterior margins of branched rays delineated by dark pigmentation. Dorsal fin with patch of dark pigmentation covering distal one-half of last un- branched and two anterior branched rays, becoming narrower and confined to fin margin posteriorly; seventh and eight branched rays unpigmented. Pectoral fin with scattered, large, light brown chromatophores. Pelvic fin unpigmented. ECOLOGY.—Taphom (1992:171) summarized the conditions inhabited by Creagrutus bolivari as "flowing waters" over rocky substrates in the Andean piedmont and the Llanos (sa- vannahs) of the Rio Orinoco basin. The diet of the species con- sists of drifting or benthic organisms. Creagrutus bolivari is moderately abundant in portions of the Rio Orituco system in the central portion of its range (Machado-Allison and Moreno, 1993). Ortaz (1997:1147) reported on the reproductive cycle of a species cited as Creagrutus bolivari from the Rio Orituco in north central Venezuela. That author utilized Schultz (1944) and Gery (1977) as the basis for that identification. Unfortu- nately the keys provided by those two authors do not discrimi- nate C. bolivari from the two other species that occur in the Rio Orituco basin, C. melasma and C. taphorni. It is therefore im- possible to ascertain which of the three species was studied by Ortaz (1997). In the western portions of its range C. bolivari was captured together with C. atratus. COMMON NAME.—Venezuela, Rio Apure system: "Diente- frio, buck-toothed tetra" (Taphorn, 1992:171). DISTRIBUTION.—Creagrutus bolivari is widely distributed in an arc across the Rio Orinoco basin from the Rio Metica, which is a component of the Rio Meta basin in Colombia in the west, through northern Venezuela, to somewhere within Estado de Monagas, Venezuela, in the east (Figure 28, stars; exact co- ordinates of the Estado de Monagas record could not be deter- mined). COMPARISONS.—Creagrutus bolivari is a quite distinctive species with a steeply sloping predorsal region of the body and an elongate, arcuate humeral bar; these attributes were well represented in the original description (Schultz, 1944:334). The distribution of the species overlaps those of a number of its congeners in the main portion of the Orinoco basin, but it can be readily distinguished by the just-cited characters and the features noted in "Key to Species of Creagrutus in the Rio Orinoco Basin." GEOGRAPHIC VARIATION.—Population samples of Creagru- tus bolivari examined during this study mostly originated in the central and eastern portions of the Rio Orinoco basin in Vene- zuela (Figure 28). A series of samples from the upper portions of the Rio Meta basin in the western portions of the basin in Colombia also are identified herein as C. bolivari as they agree with the more eastern samples in all meristic and morphometric features, other than for having a shift in the range of the total number of vertebrae. Within the central and eastern portions of the Orinoco basin, C. bolivari has 35 to 38, rarely 38, verte- brae, whereas the Colombian population samples have 36 to 38, typically 37 or 38, vertebrae. Further collections from inter- vening areas are necessary to determine whether this variation demonstrates any discrete pattern. REMARKS.—Eigenmann (1921, pi. 93: fig. 7; 1922:38; 1927: 421) reported Creagrutus beni from various localities along the eastern slope of the Colombian Andean Cordilleras (Rio Guad- rigua, Rio Roncador, and Quebrada Cramalote, Villavicencio) in the western portions of the Rio Orinoco basin. Examined specimens from two of those localities (Rio Guadrigua, Rio Roncador) have proved to be Creagrutus bolivari. Although we have not examined the specimens from Quebrada Cramal- ote, Villavicencio, their locality and the available information on the distribution of Creagrutus species in that region indicate that those specimens are also C. bolivari. Myers and Roberts (1967:249) stated that Creagrutus boli- vari is probably a synonym of C. phasma Myers (1927). This view was reiterated by Mago-Leccia (1970:70) in a footnote. We have examined the types and other material of both species and found that they are distinct in various features, including 82 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY premaxillary dentition (C. bolivari, typically with 6 teeth in the primary premaxillary series versus 5 teeth in that series in C. phasma), body shape (deeper in C. bolivari, compare Figures 28 and 79), and form of the humeral mark (dorsally arcuate and ventrally vertical in C. bolivari, compared with gently arcuate overall in C. phasma). Some differences exist between our observations on Crea- grutus bolivari and those reported by Schultz (1944) in the original description of the species. The number of gill rakers in the species was reported by Schultz (1944:335) to be "about 5 +9," whereas 5+10 was the lowest count we obtained in our survey of the type series and other material of the species. There are usually 6 or 7 gill rakers on the upper limb and 10 or 11 on the lower limb of the first gill arch. In addition, Schultz (1944) stated that with the exception of the dorsal fin, the fins were unpigmented. As described above, we found that only the pelvic fins are unpigmented in C. bolivari. Schultz (1944:336) commented that Creagrutus bolivari dif- fers from all other species in the genus, except C. brevipinnis, in having a low number of (branched) anal-fin rays (8 or 9 in C. bolivari reported by Schultz; 8-10 found in the present study; versus 9 or 10 in C. brevipinnis, Harold and Vari, 1994). Among the Creagrutus species described prior to Schultz's pa- per, however, similarly low counts also occur in C. magdalenae Eigenmann (9-11; Harold and Vari, 1994:17, table 5), C. atrisignum (9 or 10), C. beni (9-11), and C. peruanus (9-11) (see species accounts in this paper for data on the latter three species). Schultz (1944) also stated that C. brevipinnis has a deeper body and is less elongate than C. bolivari. We measure body depth as the distance from the dorsal-fin origin to the lat- eral base of the pelvic fin. The range for this value in the two species (C. brevipinnis and C. bolivari) shows pronounced overlap with the range in C. brevipinnis and extends only slightly above that of C. bolivari. Creagrutus brevipinnis, how- ever, has a shallower caudal peduncle, giving it a more elon- gate appearance posteriorly, which, in turn, makes the relative body depth appear greater (Harold and Vari, 1994:18, fig. 10). This might account for Schultz' comment. Creagrutus magdalenae, the second Trans-Andean species with which Schultz (1944) compared C. bolivari, is quite distinct from that species, with a uniquely deepened body and caudal area (Harold and Vari, 1994:16, fig. 9). Creagrutus bolivari differs from the other Cis-Andean species listed above in various fea- tures or combinations of features listed in the "Diagnosis" of the species (see above). One specimen from the Rio Guarapiche, in the Estado de Monagas in the region north of the delta of the Rio Orinoco (USNM 163155), appears similar to C. bolivari but clearly dif- fers from it in the configuration of the anal fin. The specimen is tentatively identified as C. aff. bolivari. The location where the specimen was collected lies at the eastern extreme of the known distribution of the species (Figure 28). A detailed treat- ment of this specimen and an evaluation of the significance of the difference in the anal-fin form must await the collection and examination of additional material from the eastern por- tions of the Rio Orinoco basin. MATERIAL EXAMINED.—579 specimens (64,26.3-61.0). COLOMBIA. Rio Roncador, E slope of Cordillera Oriental, E of Bogota, CAS 69302, 2 (formerly IU 13179). Rio Guadrigua, E slope of Cordillera Oriental, E of Bogota, CAS 69301, 3 (for- merly IU 13174). Meta: Rio Metica, approximately 1.5 km E of Rajote (3°56'S, 73°03'W), ANSP 134160, 50 (9, 38.6-50.2). Rio Meta basin, Rio Ocoa, approximately 15 km E of Villavice- ncio, NRM 16847, 11 (6, 26.3-61.0). Rio Meta basin, Cano Union, tributary to Rio Ocoa, where crossed by road between Villavicencio and Acacias, NRM 16844, 22 (29.4-54.7). Rio Meta basin, Cano Candelaria, tributary to Rio Negro, approxi- mately 20 km SW of Villavicencio, NRM 16846, 3. Rio Meta basin, Rio Manacasias, Restrepo, MHNG 2183.39, 4. Rio Met- ica, approximately 3 km SE of Hacienda Mozambique (3°57'N, 73°02'W), ANSP 134081, 50. VENEZUELA. Aragua: Rio Carmen de Cura, 5 km SE of Carmen de Cura (latter locality at 9°48'N, 66°50'W), MHNLS 525, 21 (10, 36.7-44.4). Rio Guarico and tributaries between San Sebastion and San Casimiro (latter locality at 10°00'N, 67°01'W), USNM 121497, 1 (50.2, holotype of Creagrutus bo- livari); USNM 121498, 82 (paratypes of Creagrutus bolivari; 9, 35.7-48.3). Barinas: Rio Santo Domingo, S of city of Bari- nas (approximately %oWWt 70°12'W), MCNG 7432, 9. Boli- var: Rio Orocopiche, on road from Caicara to Ciudad Bolivar (approximately 8°07'N, 63°39'W), MBUCV V-18110, 5. Pools and beaches in front of Salto de Icutu, Rio Nichare system, Rio Caura basin (5°53'00"N, 64°51'W), MCNG 21492, 20 (5, 37.8-46.0). Rio Matuanta, 12 km E of Ciudad Bolivar, MHNLS 518, 48. Rio Cuchivero, at Cuchivero ferry crossing (7°29'N, 65°35'W), ANSP 159830, 43; MBUCV V-18065, 6 (2, 40.2-52.3). Rio Cariapo, at bridge along highway from Caicara to Ciudad Bolivar ( 7 ^ 3 ^ , 63°49'42"W), MBUCV V- 18037, 29; ANSP 159833, 1; ANSP 159831, 83. Guarico: Rio Orituco, along road from Calabozo, below bridge, MBUCV V- 21432, 3; MBUCV V-21449, 1. Rio Oriruco, bridge at road from Calabozo to Cazorla, MBUCV V-21933, 1. Rio Orituco, 15 km SSE of Calabozo on Cazorla Road (8°48H 67°26'W), ANSP 139534, 3. Rio Orituco, MBUCV V-21508, 4. Guariq- uito Creek, Rio Orinoco basin, 6 km E of San Jose, INHS 69458, 4. Rio San Jose on W boundary of Aquaro-Guariquito National Park, INHS 69530, 8. Monagas: Rio Arco, MHNLS 9251, 2. Portuguesa: Rio Bocon6, in front of "Sun-Sun," MBUCV V-8378, 8; USNM 327935, 2. Rio Bocono, Puerto Sun-Sun, in front of port, MBUCV V-9464, 15. Rio Ospino, at Ospino (9°18'N, 69°27'W), MBUCV V-8404, 3. Rio Tucu- pido, immediately above junction with Rio Guanare, just be- hind the Santuario de la Coromoto, approximately 1.7 km SW of Guanare (latter locality at 9°03'N, 69°45'W), just above junction with Rio Guanare, UF 32318, 31. The following lot, discussed above (see "Remarks"), is tenta- tively assigned to C. bolivari. VENEZUELA. Monagas: Rio Guarapiche, Caicara, USNM 163155,1. NUMBER 613 83 Creagrutus britskii, new species FIGURES 28, 31, TABLE 11 DIAGNOSIS.—The combination of the possession of premax- illary dentition arranged in the three components generalized for most of the species of Creagrutus and Piabina without a distinctly larger gap between the first and second teeth of the primary series, 2 or 3 teeth on the maxilla, typically 6 teeth in the primary series on the premaxilla, 4 or 5 teeth on each den- tary, 36 to 39 lateral line scales without a lamellar process over each pore, 9 to 11 predorsal median scales, 5 scales rows be- tween the dorsal-fin origin and the lateral line, 9 to 11 branched anal-fin rays, 36 or 37 vertebrae, the 6 or 7 gill rakers on the upper and 10 to 12 gill rakers on the lower limb of the first gill arch, the distance from the dorsal-fin origin to the pelvic-fin in- sertion (25.4%-32.6% of SL), the postorbital head length (38.1%—45.6% of HL), the snout length (28.3%-33.3% of HL), the interorbital width (30.3%-34.1% of HL), the depth of the caudal peduncle (11.4%-13.9% of SL), the well-developed third infraorbital with the ventral margin of its anterior portion contacting the preopercle in larger specimens, the moderately vertically elongate humeral mark not in the form a ventrally ta- pering vertical bar and lacking a distinct extension ventrally or a secondary patch of pigmentation dorsal to the primary mark, the lack of a series of dark spots along the midlateral surface of the body, and the lack of a discrete patch of dark pigmentation on the middle portion of the anterior dorsal-fin rays distinguish C. britskii from the other species in the clade composed of Cre- agrutus and Piabina. DESCRIPTION.—Morphometric and meristic data for Crea- grutus britskii in Table 11. Head relatively robust. Body pro- portionally moderately more elongate in smaller individuals, progressively more robust anteriorly with increasing body size. Greatest body depth at, or barely anterior to, dorsal-fin origin in individuals up to approximately 45 mm SL, shifted anteri- orly in most larger specimens, particularly those with distended abdomens. Dorsal profile of head distinctly convex from mar- gin of upper lip to vertical through posterior nostril, straight from that point to tip of supraoccipital spine in all specimens larger than 20 mm SL. Interorbital region gently convex. Pre- dorsal profile of body continuing that of posterior portion of head and nearly straight to dorsal-fin origin in specimens up to approximately 35 mm SL, becoming progressively more con- vex in larger individuals. Predorsal region of body in preserved specimens transversely flattened anteriorly in all specimens larger than 20 mm SL, transversely flattened region extending nearly to dorsal-fin origin in smaller specimens, limited to an- terior one-half of predorsal region in larger specimens that, in turn, have medial middorsal ridge along posterior one-third of predorsal region. Ventral profile of head gently convex overall anteriorly, with barely apparent obtuse angle at anteroventral corner of dentary, nearly straight from that region to isthmus. Ventral profile of body nearly straight up to approximately 35 mm SL, increasingly convex in larger individuals. TABLE 11.—Morphometrics and meristics of Creagrutus britskii. new species (A) holotype of C. britskii. MZUSP 40537; and (B) paratypes of C. britskii (n= 56). Standard length expressed in mm; measurements 1 to 14=percentages of standard length; 15 to 18=percentages of head length. Characters Standard length 1. Snout to anal-fin origin 2. Snout to pelvic-fin insertion 3. Snout to pectoral-fin insertion 4. Snout to dorsal-fin origin 5. Dorsal-fin origin to hypural joint 6. Dorsal-fin origin to anal-fin origin 7. Dorsal-fin origin to pelvic-fin insertion 8. Dorsal-fin origin to pectoral-fin insertion 9. Caudal peduncle depth 10. Pectoral-fin length 11. Pelvic-fin length 12. Dorsal-fin length 13. Anal-fin length 14. Head length 15. Postorbital head length 16. Snout length 17. Bony orbital diameter 18. Interorbital width Lateral line scales Scale rows between dorsal-fin origin and lateral line Scale rows between anal-fin origin and lateral line Predorsal median scales Branched dorsal-fin rays Branched anal-fin rays Branched pelvic-fin rays Pectoral-fin rays Vertebrae A B Morphometrics 52.5 67.9 47.2 26.3 51.4 52.6 35.5 30.9 35.0 13.3 22.4 18.7 24.8 18.7 27.5 45.2 31.3 35.4 32.6 27.3^*7.5 59.6-68.1 43.3-52.3 22.9-27.2 45.1-52.0 52.1-58.0 28.2-36.0 25.4-32.6 30.1-35.8 11.4-13.9 17.1-22.4 13.7-17.9 20.5-24.8 17.0-20.2 23.7-27.5 38.1-45.6 28.3-33.3 30.1-38.2 30.3-34.1 Meristics 38 5 3 11 8 9 6 13 36 36-39 5 3-4 9-11 8 9-11 6 11-13 36-37 Head obtusely pointed in lateral view, more compressed lat- erally in dorsal view. Upper jaw longer than, and overhanging, lower jaw. Snout fleshy anteroventrally, with scattered papillae proximate to margin of upper lip. Lateral surface of upper lip with scattered papillae. Ventral margin of upper lip and fleshy folds and plicae extending between outer and medial premaxil- lary teeth with numerous papillae. Lower lip very fleshy with numerous papillae along anterodorsal margin and scattered pa- pillae anteroventrally. Infraorbital series moderately developed. Anterior portion of ventral margin of third infraorbital falling distinctly short of horizontal limb of preopercle in smaller specimens, progres- sively approaching that bone ontogenetically, and in contact with that portion of the preopercle in larger individuals. Poste- rior margins of third through fifth infraorbitals falling distinctly short of vertical limb of preopercle. Premaxillary dentition in three series: primary row curved or very slightly sigmoid, typically with 6 teeth (only 5 teeth present on one premaxilla in one examined specimen) without pronounced gap between first and second tooth of series; trian- gular cluster of 3 larger teeth with posterolateral tooth largest and medial teeth of contralateral clusters in contact; and single 84 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY FIGURE 31.—Creagrutus britskii, new species, holotype, MZUSP 40537, 52.5 mm SL; Brazil, Goias, Iaciara, Ribeirao Macambira, near bridge on highway GO 112 (approximately 14°20'S, 46C45'W). tooth of form similar to that of primary series lying lateral to fourth tooth of primary premaxillary tooth row, or lateral to re- gion of contact of fourth and fifth teeth. Maxilla with 2 or 3 tri- cuspidate teeth. Dentary with 4 or 5 teeth, anterior three teeth largest; first and second subequal and distinctly larger than third tooth; latter, in turn, notably larger than fourth tooth. Teeth all tricuspidate (when 4 teeth present) or last tooth coni- cal, or nearly so (when 5 teeth present). Dorsal-fin rays typically ii,8, rarely iii,8 (in only 3 examined specimens). Dorsal-fin origin at, to slightly posterior of, verti- cal through pelvic-fin insertion. Profile of distal margin of dor- sal fin slightly concave. Anal-fin rays ii,9-ll. Profile of distal margin of anal fin slightly concave. Mature males with many hooks on at least first and second branched anal-fin rays, some specimens with few hooks also present on third branched anal- fin ray. Pectoral-fin rays i, 10-12. Tip of pectoral fin falling dis- tinctly short of pelvic-fin insertion in smaller individuals, ex- tending to, or occasionally surpassing, that point in largest indi- viduals. Pelvic-fin rays i,6,i in all examined specimens. Tip of pelvic fin extending posteriorly to anus or anal-fin insertion. Mature males with hooks on all branched pelvic-fin rays. Gill rakers 6-7+10-12. COLORATION IN ALCOHOL.—Overall ground coloration of relatively recently collected specimens tan. Dorsal surface of head with scattered surface chromatophores posteriorly, with chromatophore field becoming denser anteriorly, particularly over snout. Field of deep-lying, dark chromatophores on mem- branes overlying brain, chromatophore field most intense pos- terior of epiphyseal bar, degree of intensity of overall pigmen- tation variable between individuals. Region anterior to nostrils with crescent-shaped field of denser chromatophores some- times continuous with narrow band of chromatophores along ventral and posterior margins of orbit. Region posterior of orbit with scattered chromatophores on infraorbitals and opercle. Scales of posterodorsal portion of body with marginal series of dark chromatophores separated from basal patch of chro- matophores by hyaline region. Pigmentation more intense ante- riorly in smaller specimens and darker overall in larger individ- uals. Humeral mark vertically elongate, pigmentation most intense in central portion of mark. Central region sometimes expanded horizontally compared with remainder of mark. Dor- sal portion of mark less intensely pigmented, with nearly verti- cal margins, or more often slightly arching anteriorly. Dorsal portion of mark merging into overall darker pigmentation of dorsal portion of body. Ventral portion of humeral mark below intensely pigmented region tapering ventrally. Midlateral stripe formed mostly by deep-lying, dark chromatophores; stripe ex- tending posteriorly from slightly behind humeral mark to cau- dal peduncle, most obvious on posterior two-thirds of body. Dorsal fin with last unbranched and first branched rays often outlined with dark chromatophores. Distal portions of mem- branes between anterior branched rays with scattered, large, dark chromatophores. Anterior two-thirds of branched anal-fin rays outlined basally by dark pigmentation; pigmentation ex- tending further along rays on anterior rays. Caudal-fin rays, particularly central, dorsalmost, and ventralmost rays outlined by dark chromatophores. Basal portions of middle rays with diffuse concentration of darker chromatophores, giving appear- ance of indistinct spot in some specimens. Pectoral and pelvic fins hyaline. ETYMOLOGY.—The species name, britskii, is in honor of Heraldo Britski, Museu de Zoologia of the Universidade de Sao Paulo, Brazil, in recognition of his many contributions to our understanding of South American freshwater fishes and of his assistance to the senior author over the years. ECOLOGY.—Two of the paratype lots of Creagrutus britskii (USNM 292226, 292214) were collected in small upland riv- ers, 6-25 m in width, with bottoms formed by rubble, gravel, bedrock, and silt. Turbidity was moderate, and current ranged from slow to swift. DISTRIBUTION.—Creagrutus britskii is known only from the southeastern portions of the Rio Tocantins basin (Figure 28, tri- angles). MATERIAL EXAMINED.—126 specimens (57,27.3-52.5). HOLOTYPE.—BRAZIL. Goias: Iaciara, Ribeirao Macambira (approximately 14°20'S, 46°45'W), near bridge on highway NUMBER 613 85 GO 112, collected by J.C. de Oliveira and W.J.M. Costa, 14 Sep 1988, MZUSP 40537, 1 (52.5). PARATYPES.—56 specimens (56, 27.3-47.5). BRAZIL. Goids: Iaciara, Ribeirao Macambira (approxi- mately 14°20'S, 46°45'W), near bridge on highway GO 112, collected with holotype, MZUSP 50540, 12 (33.7-43.5); USNM 340952, 4 (34.8-42.7; 2 specimens cleared and coun- terstained for cartilage and bone). Iaciara, Rio Prata above bridge on highway GO 112 (approximately 14°20'S, 46°45'W), collected by J.C. de Oliveira and W.J.M. Costa, 14 Sep 1988, MZUSP 46546, 18 (31.2-41.0). Rio Tocantins basin, Ribeirao Cangalha, at road, 14 air km NNE of Formosa (15°24'S, 47°17'W), collected by W.C. Starnes et al., 13 Nov 1984, USNM 292214, 3 (42.4-46.8). Ribeirao Paranoa do Meio, at road crossing, 11 air km NNE of Formosa (approximately 15°25'S, 47°18'W), collected by W.C. Starnes et al., 13 Nov 1984, USNM 292226, 13 (27.3-46.6). Minacu, tributary of Corrego Lageado, left bank tributary of Rio Tocantins, along road to Porto Rubiao (approximately 13°38'S, 48°19'W), col- lected by D.F. Moraes, Jr. et al., 16 Jan 1988, MNRJ 13048, 6 (39.9-47.5). NONTYPE SPECIMENS.—69 specimens. BRAZIL. Golds: Ribeirao Angelicu, above entrance to Cav- erna da Angelicu, Sao Domingos (approximately 13°36'S, 46°24'W), MZUSP 40629, 2. Municipio de Monte Alegre de Goias, Rio Bezerra, right bank tributary of Rio Parana, MZUSP 40702, 3. Iaciara, Ribeirao Macambira (approximately 14°20'S, 46°45'W), near bridge on highway GO 112, MZUSP 50541, 63 (collected with holotype); MZUSP 40534, 1. Creagrutus calai, new species FIGURES 32, 33, TABLE 12 DIAGNOSIS.—The combination of the possession of premax- illary dentition arranged in the three components generalized for most of the species of Creagrutus and Piabina without a distinctly larger gap between the first and second teeth of the primary series, typically 6 teeth in the primary series of each premaxilla, 3 maxillary teeth, 5 teeth on each dentary, 9 to 11 median predorsal scales, 37 to 41 lateral line scales without a lamellar process over each pore, 4, rarely 5, scale rows between the dorsal-fin origin and the lateral line, 2 post-anal scales to the anal-fin origin, 10 to 12 branched anal-fin rays, 7 to 9 gill rakers on the upper limb and 11 to 13 gill rakers on the lower limb of the first gill arch, the head length (24.3%-27.5% of SL), the postorbital head length (41.2%-46.1% of HL), the in- terorbital width (28.8%-32.3% of HL), the contact between the ventral margin of the third infraorbital and the horizontal limb of the preopercle in larger specimens, the presence of a hori- zontally elongate, darkly pigmented, middorsal mark immedi- ately posterior of the head, the lack of a distinct spot of dark pigmentation at the base of the middle caudal-fin rays, the overall vertically elongate, irregularly shaped, humeral mark TABLE 12.—Morphometrics and meristics of Creagrutus calai, new species: (A) holotype of C. calai, ANSP 130527, and (B) paratypes of C. calai (n=58). Standard length is expressed in mm; measurements 1 to 14=percentages of standard length; 15 to 18=percentages of head length. Characters Standard length 1. Snout to anal-fin origin 2. Snout to pelvic-fin insertion 3. Snout to pectoral-fin insertion 4. Snout to dorsal-fin origin 5. Dorsal-fin origin to hypural joint 6. Dorsal-fin origin to anal-fin origin 7. Dorsal-fin origin to pelvic-fin insertion 8. Dorsal-fin origin to pectoral-fin insertion 9. Caudal peduncle depth 10. Pectoral-fin length 11. Pelvic-fin length 12. Dorsal-fin length 13. Anal-fin length 14. Head length 15. Postorbital head length 16. Snout length 17. Bony orbital diameter 18. Interorbital width Lateral line scales Scale rows between dorsal-fin origin and lateral line Scale rows between anal-fin origin and lateral line Predorsal median scales Branched dorsal-fin rays Branched anal-fin rays Branched pelvic-fin rays Pectoral-fin rays Vertebrae A B Morphometrics 54.2 62.4 45.4 24.0 45.6 57.7 31.2 26.0 30.8 10.9 18.6 18.4 19.2 16.4 24.5 41.4 29.3 35.4 32.0 33.0-66.0 61.2-66.0 45.1-48.1 23.1-26.8 44.4-49.2 54.1-59.5 28.8-34.2 25.6-29.0 30.5-34.1 10.4-12.2 17.9-22.0 14.6-18.6 18.8-22.6 15.0-18.5 24.3-27.5 41.2-46.1 26.4-31.7 31.1-35.6 28.8-32.3 Meristics 39 4 3 10 8 11 6 14 37 37-41' 4-52 3-43 9-11 8 10-12 6-74 13-15 36-39 Thirty-seven and 41 lateral line scales each present in only 1 paratype. 2Five scale rows between dorsal-fin origin and lateral line present in only 1 paratype. 3Four scale rows between anal-fin origin and lateral line present in only 1 paratype; larger paratypes with sheath of much smaller scales along base of anterior anal-fin rays. 4Seven branched anal-fin rays present only in some larger paratypes. most intensely pigmented in the area above the lateral line and without a secondary, dorsal patch of pigmentation, the absence of a distinct patch of pigmentation on the dorsal fin, and the lack of a series of dark spots along the midlateral surface of the body distinguishes Creagrutus calai within the clade formed by Creagrutus and Piabina. DESCRIPTION.—Morphometric and meristic data for Crea- grutus calai in Table 12. Head and body relatively slender in smaller specimens, becoming increasingly robust in larger specimens. Greatest body depth approximately at dorsal-fin or- igin in specimens up to 40 mm SL, falling between dorsal-fin origin and vertical midway between pectoral- and pelvic-fin in- sertions in larger specimens. Dorsal profile of head distinctly convex from margin of upper lip to vertical through posterior 86 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY FIGURE 32.—Creagrutus calai. new species, holotype, ANSP 130527, 54.2 mm SL; Colombia, Meta, Rancho El Viento, across Rio Meta from Puerto Lopez (4°08X 72°39'W). nostril, straight from that point to tip of supraoccipital spine. Interorbital region somewhat flattened transversely. Predorsal profile of body straight to slightly convex. Predorsal surface of body with obtuse median ridge posteriorly. Ventral profile of head with variably obvious obtuse angle at anteroventral comer of dentary, straight to very gently convex from angle to isth- mus. Prepelvic profile of body convex, increasingly so in larger individuals. Prepelvic region of body obtusely flattened trans- versely. Head obtusely flattened in lateral view and moderately com- pressed laterally in dorsal view. Upper jaw longer than, and overhanging, lower jaw. Anterior portion of snout fleshy with scattered papillae. Papillae more concentrated along ventral surface of upper lip and on fleshy folds and plicae extending between outer and medial premaxillary teeth. Anterior and par- ticularly dorsal surfaces of lower lip with numerous papillae. Infraorbital series moderately well developed in all speci- mens larger than 35 mm SL, proportionally somewhat more ex- tensive posteriorly in larger individuals. Ventral margin of third infraorbital contacting, or nearly contacting, horizontal limb of preopercle. Posterior and ventral margins of third infraorbital approximately at right angles, with posteroventral corner of bone slightly rounded. Posterior margins of third through fifth infraorbitals separated from vertical limb of preopercle; gap between infraorbitals and preopercle progressively decreasing dorsal ly. Premaxillary dentition in three series: primary row slightly curved to slightly sigmoid, typically with 6 teeth (5 teeth present on one side of head in two individuals), without pro- nounced gap between first and second tooth of series but with medial tooth separated from comparable tooth of contralateral series; triangular cluster of three somewhat to distinctly larger teeth; and single tooth of form similar to that of primary series occurring lateral to primary series; when 6 teeth present in pri- mary series, single tooth of form similar to that of primary se- ries located lateral to fourth tooth of primary series or lateral to area of contact of fourth and fifth teeth of primary series, when 5 teeth present in primary series, single tooth of form similar to that of primary series located lateral to third tooth of primary series. Maxillary teeth 3, tricuspidate. Dentary teeth 5, first two teeth largest, with first tooth about two-thirds height of second tooth and distinctly narrower. Third dentary tooth about one- third height of second tooth. Remaining dentary teeth half as high as third tooth and tricuspidate. Dorsal-fin rays ii,8 in all specimens. Dorsal-fin origin ap- proximately at vertical through pelvic-fin insertion. Profile of distal margin of dorsal fin straight to slightly concave. Anal-fin rays ii, 10-12 or iii,10-12, with first unbranched ray very short when three unbranched rays present. Distal profile of anal-fin concave, more so in larger individuals. Anal-fin hooks present on first and second or first through third rays in mature males. Pectoral-fin rays i,12-14. Tip of pectoral fin reaching posteri- orly to within 2 or 3 scales of pelvic-fin insertion. Pelvic-fin rays i,6,i or i,7; i,7 occurs only in larger specimens. Tip of pel- vic fin reaching posteriorly to, or nearly to, anal-fin origin. Ma- ture males with pelvic-fin hooks present on all branched rays (6 or 7 rays depending on number of branched rays in an individ- ual). Gill rakers 7-9+11-13. COLORATION IN ALCOHOL.—Overall ground coloration of specimens tan. Dorsal surface of head with deep-lying larger stellate chromatophores and smaller surface chromatophores; chromatophore concentration greater in larger individuals. Chromatophore field extending onto snout, upper lip, and re- gion anterior and anteroventral to orbit. Region anterior to nos- trils with more intensely pigmented, crescent-shaped field of dark chromatophores. Smaller and medium-sized individuals with posteroventrally angled stripe of dark chromatophores ex- tending from under nostril to anteroventral margin of eye; stripe subsumed into overall darker pigmentation in that region in larger individuals. Fourth and fifth infraorbitals, dorsal por- tion of third infraorbital, and dorsal portion of opercle with dis- persed dark chromatophores in juveniles; chromatophore field more concentrated in larger individuals, with dark chromato- NUMBER 613 87 FIGURE 33.—Map of central and northern South America showing geographic distribution of Creagrutus calai (squares, l=type locality), Creagrutus changae (dots, 2=type locality), Creagrutus cochui (triangles, 3=type locality), and Creagrutus cracentis (star, 4=type locality) (some symbols represent more than one locality or lot of specimens). phores on cheek posterior to third infraorbital, lower portion of opercle, and along subopercle. Lower jaw with field of small dark chromatophores anteriorly. Scales of dorsolateral portion of body with dense field of small dark chromatophores and distal pattern of larger, more diffuse chromatophores; chromatophore fields separated by hy- aline or less pigmented region. Less pigmented areas apparent as reticulate pattern on dorsolateral region of body. Scales ven- tral to that area with irregular pattern of scattered, dark chro- matophores slightly more concentrated along scale margins dorsal to lateral line. Humeral mark vertically elongate; most intensely pigmented in area immediately dorsal of lateral line. Intensely pigmented region of humeral mark more developed horizontally than regions dorsal and ventral to it. Humeral mark continuing ventrally from intensely pigmented region as more diffuse ventrally attenuating region of dark pigmentation. Portion of mark dorsal to central section less intensely pig- mented, typically somewhat anteriorly arching and extending one to one and one-half scales dorsally from central region. Midlateral stripe well developed but less intensely pigmented anteriorly, falling 3 or 4 scales short of posterior margin of hu- meral spot in specimens smaller than approximately 40 mm SL; stripe extending anteriorly to posterior margin of humeral mark; anterior portion somewhat masked by guanine in some specimens. Dorsal-fin rays outlined by dark chromatophores and with scattered, dark chromatophores on distal portions of anterior rays. Anal fin with small chromatophores outlining basal por- tions of anterior rays and scattered chromatophores on distal portions of anterior branched rays. Middle caudal-fin rays more intensely pigmented than remainder of fin; pigmentation form- ing faint stripe in specimens of approximately 40 mm SL, and distinct stripe in larger individuals. Remaining caudal-fin rays outlined by chromatophores, with greater intensity of pigmen- SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY tation on dorsalmost and ventralmost portions of fin. Pectoral and pelvic fins with rays lightly outlined by series of dark chro- matophores. ETYMOLOGY.—The specific name, calai, is in honor of Plu- tarco Cala, Universidad Nacional de Colombia, in recognition of his many contributions to our understanding of Colombian freshwater fishes, and for his assistance to the authors. ECOLOGY.—Stomach contents of two specimens of Creagru- tus calai prepared for clearing and staining in this study con- sisted of chopped-up seeds and insect parts. DISTRIBUTION.—Creagrutus calai occurs in the western por- tions of the Rio Meta basin in eastern Colombia (Figure 33, squares). MATERIAL EXAMINED.—66 specimens (59, 33.0-66.0). HOLOTYPE.—COLOMBIA. Meta: Unnamed stream on Ran- cho El Viento, across Rio Meta from Puerto Lopez (4°08'N, 72°39'W), collected by J.E. Bohlke and N.R. Foster, 20 May 1969, ANSP 130527, 1(54.2). PARATYPES.—58 specimens (58,33.0-66.0). COLOMBIA. Meta: Unnamed stream on Rancho El Viento, across Rio Meta from Puerto Lopez (4°08'N, 72°39'W), col- lected with holotype, ANSP 177718, 12 (40.7-58.0); USNM 353307, 4 (42.0-56.1). Rancho El Viento, Cano Emma (4°08'N, 72°39'W), collected by J.E. Bohlke and N.R. Foster, 18 Mar 1973, ANSP 139149, 18 (33.0-65.3); USNM 353304, 4 (42.9-59.5; 2 specimens cleared and counterstained). Rio Meta basin, Cano Candelaria, tributary to Rio Negro, approxi- mately 20 km SW of Villavicencio, collected by A.M.C. Silf- vergrip, 10 Jan 1988, NRM 43015, 2 (64.1-66.0). Rio Meta ba- sin, Caiio Quenane, tributary to Rio Negro, where crossed by road between Villavicencio and Puerto Lopez (4°02'N, 73°10'W), collected by A.M.C. Silfvergrip, 7 Jan 1988, NRM 16849, 10 (46.3-60.0); USNM 353868, 2 (46.6-56.2). Rio Meta basin, Cano Quenane, tributary to Rio Negro, where crossed by road between Villavicencio and Puerto Lopez (4°02'N, 73°10'W), collected by A.M.C. Silfvergrip, 7 Jan 1988, NRM 16848,1 (53.9). Rio Meta basin, Cano Union, trib- utary to Rio Ocoa, where crossed by road between Villavicen- cio and Acacias, collected by A.M.C. Silfvergrip, 7 Jan 1988, NRM 43016, 5 (40.6-58.4). NONTYPE SPECIMENS.—7 specimens. COLOMBIA. Meta: Cordillera Macarena, small brook into Rio Guayabero, 5 mi (8.0 km) below El Refugio, elev. 900 ft (approximately 274 m), CAS 153758, 6. Villavicencio, Rio Meta basin (4°09'N, 73°39/W), USNM 100790,1. Creagrutus changae, new species FIGURES 33,34, TABLE 13 DIAGNOSIS.—The combination of the possession of premax- illary dentition arranged in the three components generalized for most of the species of Creagrutus and Piabina without a TABLE 13.—Morphometrics and meristics of Creagrutus changae, new spe- cies: (A) holotype of C. changae, MUSM 8858; and (B) paratypes of C. chan- gae (n=50). Standard length is expressed in mm; measurements 1 to 14=per- centages of standard length; 15 to 18=percentages of head length. Characters Standard length 1. Snout to anal-fin origin 2. Snout to pelvic-fin insertion 3. Snout to pectoral-fin insertion 4. Snout to dorsal-fin origin 5. Dorsal-fin origin to hypural joint 6. Dorsal-fin origin to anal-fin origin 7. Dorsal-fin origin to pelvic-fin insertion 8. Dorsal-fin origin to pectoral-fin insertion 9. Caudal peduncle depth 10. Pectoral-fin length 11. Pelvic-fin length 12. Dorsal-fin length 13. Anal-fin length 14. Head length 15. Postorbital head length 16. Snout length 17. Bony orbital diameter 18. Interorbital width Lateral line scales Scale rows between dorsal-fin origin and lateral line Scale rows between anal-fin origin and lateral line Predorsal median scales Branched dorsal-fin rays Branched anal-fin rays Branched pelvic-fin rays Pectoral-fin rays Vertebrae A B Morphometrics 75.5 64.1 46.2 25.2 47.5 56.4 34.0 28.6 34.0 12.7 20.8 16.7 22.7 17.6 26.6 46.0 28.4 31.8 30.3 35.9-66.9 61.1-66.3 44.2-50.1 23.5-28.1 46.9-50.6 53.6-57.9 31.0-35.1 26.8-31.1 31.6-36.7 11.7-13.5 18.9-23.1 15.0-17.6 21.9-25.3 17.2-20.7 25.2-29.5 42.7-49.0 25.3-30.9 31.0-36.4 27.7-31.3 Meristics 40 5 4 11 8 11 7 14 38 39-43 5-6 4 9-11 7-8' 10-11 6-7 13-14 37-39 'Seven branched dorsal-fin rays present in only 2 paratypes. distinctly larger gap between the first and second teeth of the primary series, 6 teeth in the primary series of each premaxilla, 3 or 4 teeth on each maxilla, 5 teeth on each dentary, 39 to 43 lateral line scales without a lamellar process over each pore, 9 to 11 median predorsal scales, 5 or 6 rows of scales between the lateral line and the dorsal-fin origin, 4 rows of scales be- tween the lateral line and the anal-fin origin, 2 post-anal scales to the anal-fin origin, 10 or 11 branched anal-fin rays, 37 to 39 vertebrae, 6 or 7 gill rakers on the upper limb and 9 or 10 gill rakers on the lower limb of the first arch, the interorbital width (27.7%-31.3% of HL), the well-developed third infraorbital approaching, or contacting, the horizontal limb of the preoper- cle, the lack of a series of dark spots along the midlateral sur- face of the body, the discrete, distinctly vertically elongate hu- meral mark, and the lack of a discrete patch of dark pigmentation on the anterior rays of the dorsal fin distinguishes Creagrutus changae from all members of the clade composed of Creagrutus and Piabina. DESCRIPTION.—Morphometric and meristic data for Crea- grutus changae in Table 13. Head and body relatively robust in all specimens larger than 30 mm SL. Greatest body depth at, or NUMBER 613 89 FIGURE 34.—Creagrutus changae, new species, holotype, MUSM 8858, 75.5 mm SL; Peru, Huanuco, Provincia Pachitea, Rio San Alejandro, a tributary of Rio Sungarayacu, just above junction with Rio Sungarayacu (approx- imately 9°23'S, 75° 11'W). more rarely, slightly anterior of dorsal-fin origin. Dorsal profile of head smoothly convex from tip of snout to vertical through posterior nostril, straight or very slightly convex from that point to tip of supraoccipital spine. Interorbital region slightly convex. Dorsal profile of body nearly straight anteriorly; con- tinuous with profile of head in smaller specimens, slightly con- vex with moderate change in alignment relative to that of head in larger individuals. Profile slightly angled at dorsal-fin base in relatively shallow-bodied individuals, angle more pro- nounced in deep-bodied specimens. Dorsal surface of body with predorsal median ridge proximate to dorsal fin in all indi- viduals larger than 30 mm SL. Ventral profile of head with slightly to moderately obvious obtuse angle at anteroventral corner of dentary, slightly convex from that angle to isthmus. Ventral profile of body slightly convex in most specimens, more convex in ripe females. Prepelvic region of body obtusely flattened transversely. Head pointed in both lateral and dorsal views. Upper jaw dis- tinctly longer than, and overhanging, lower jaw. Anterior por- tion of snout fleshy with numerous papillae; papillae more con- centrated along ventral margin of fleshy upper lip, and on fleshy folds and plicae extending between outer and medial premaxillary teeth. Lower lip very fleshy, with numerous papil- lae on dorsal margin and anteromedial region. Infraorbital series moderately developed. Ventral margin of third infraorbital falling distinctly short of horizontal limb of preopercle. Posterior margins of third through fifth infraorbit- als distinctly separated from vertical limb of preopercle. Premaxillary dentition in three series: primary row curved and slightly sigmoid medially, consisting of 6 teeth, without pronounced gap between first and second tooth of series but with medial tooth distinctly separated from anterior tooth of contralateral series; triangular cluster of 3 larger teeth, and sin- gle tooth of form similar to that of primary series occurring lat- eral to fourth tooth of premaxillary row. Maxilla with 3 or 4 tri- cuspidate teeth. Dentary with 5 tricuspidate teeth; first and second teeth subequal and approximately twice height of third tooth; fourth and fifth teeth much smaller and graded in size, compressed. Dorsal-fin rays typically ii,8, rarely ii,7. Dorsal-fin origin ap- proximately at vertical through pelvic-fin insertion. Profile of distal margin of dorsal fin slightly concave. Anal-fin rays typi- cally ii,10-11, rarely iii,10. Profile of distal margin of anal fin nearly straight in smaller specimens, increasingly concave in larger individuals. Anal fin in mature males with hooks occa- sionally present on last unbranched and anterior 3 to 6 branched rays. Pectoral-fin rays i, 12-13. Pectoral fin extending posteriorly to, or falling slightly short of, pelvic-fin insertion. Pelvic-fin rays i,6,i or i,7; branching of medial pelvic-fin ray limited to larger individuals. Hooks of mature males, when present, occurring on all branched pelvic-fin rays. Gill rakers 6-7 + 9-10. COLORATION IN LIFE.—(Description based on a transpar- ency of recently collected specimen from the Rio Yuyapichis (= Llullapichis), Rio Pachitea basin, Peru, provided by E. Holm, ROM.) Overall coloration bright silver, with guanine deposits particularly well developed on first through third in- fraorbitals, opercle, and central region of exposed portions of scales other than on anterodorsal and posterodorsal sections of lateral surface of body. Vertically elongate humeral mark prom- inent. Midlateral stripe obvious but not to degree as humeral mark. Region of eye dorsal to pupil blood red. Anterior anal-fin rays and lateral pelvic-fin ray white. Dark pigmentation on head, body, and fins as in alcohol-preserved specimens. COLORATION IN ALCOHOL.—Overall ground coloration of most specimens tan. Dorsal surface of head with scattered, small, dark chromatophores extending onto snout and upper lip. No indication of larger deep-lying dark chromatophores overlying brain as in some Creagrutus species. Slight concen- tration of chromatophores present anterior to nostril in speci- mens of approximately 30 to 40 mm SL, but region without ob- vious concentrations of chromatophores in larger individuals. Small dark chromatophores more concentrated anteroventral to orbit, concentration more obvious in smaller specimens. Irreg- 90 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY ular band of chromatophores outlining remaining portions of ventral and posterior orbital margins. Scattered chromato- phores over dorsal portions of infraorbital series and opercle. Scales of dorsal portion of body with dense chromatophore field over basal portion of exposed section of scales and with scattered chromatophores along margin of scales. Darkly pig- mented regions separated by hyaline crescent. Humeral mark vertically elongate, darkly pigmented in some, usually smaller, specimens, but diffuse in larger individuals. Mark extending approximately 1.5 scales ventral of, and 2 scales dorsal of, lat- eral line, with distinct dorsal limits in few specimens with prominent marks, but more typically merging imperceptibly into darker pigmentation of dorsal portion of body in speci- mens with more diffuse marks. Dorsal fin with anterior margin of first unbranched ray and distal margins of branched rays outlined with dark chromato- phores. Basal one-fourth to two-thirds of branched anal-fin rays outlined with chromatophores. Caudal-fin rays variably outlined and overlain by small dark chromatophores, giving fin overall dusky appearance. Pectoral fin ranging from hyaline to rays variably outlined by dark chromatophores. Pelvic fin hya- line. ETYMOLOGY.—The specific name, changae, is in honor of the late Fonchii Chang of the Museo de Historia Natural, Lima, in recognition of her contributions to our understanding of Pe- ruvian fishes and her assistance to the authors prior to her un- timely death. ECOLOGY.—The holotype and three of the paratype lots were collected in the middle of the main channel of the Rio San Ale- jandro over sand bottoms and rocky riffles. Three of the exam- ined lots from the Rio Pachitea basin (ROM 55853, ROM 56084, MUSM 8859) were collected in 3 to 7 m wide streams with rubble, silt, sand, gravel, and clay bottoms. Water velocity ranged from slow to fast in pools, across riffles, and in the main channel. Examination of the stomach contents of two specimens pre- pared for clearing and staining for this study indicates that the species feeds on adult and larval insects. At one locality in the Rio Chanchamayo, Department of Junin, Peru, C. changae was collected along with C. peruanus. SEXUAL DIMORPHISM.—Mature males, as shown by the pos- session of hooks on the anal-fin and pelvic-fin rays, were all smaller than 63 mm SL. Some of the larger examined speci- mens, larger than 65 mm SL, are females with well-developed eggs. DISTRIBUTION.—Creagrutus changae occurs in various western tributaries of the Rio Ucayali in the departments of Ju- nin, Pasco, and Huanuco, Peru (Figure 33, dots). REMARKS.—Steindachner (1882a) reported Creagrutus pe- ruanus without further comment from the Rio Huambo. Only Creagrutus changae is known from that basin, and Stein- dachner's report may refer to that species. MATERIAL EXAMINED.—245 specimens (62, 35.9-75.5). HOLOTYPE.—PERU. Huanuco: Provincia Pachitea, Rio San Alejandro, a tributary of Rio Sungarayacu, just above junction with Rio Sungarayacu (approximately 9°23'S, 75OH'W), col- lected by D.W. Greenfield et al., 31 Jul 1975, MUSM 8858, 1 (75.5). PARATYPES.—50 specimens (50, 35.9-66.9). PERU. Huanuco: Provincia Pachitea, Rio San Alejandro, a tributary of Rio Sungarayacu, just above junction with Rio Sungarayacu (approximately 9°23'S, 75°11'W), collected with holotype, USNM 285276, 14 (42.6-66.7; 2 specimens cleared and counterstained for cartilage and bone); FMNH 84265, 10 (49.8-61.0; collected with holotype). Provincia Pachitea, Rio Huambo, at its mouth in Rio Pachitea (approximately 9°36'S, 74°56'W), collected by E. Holm et al., 28 Jul 1988, ROM 72378, 10 (56.7-66.9); MUSM 8859, 16 (35.9-58.9). NONTYPE SPECIMENS.—194 specimens (11, 36.4-60.8). PERU. Junin: Provincia Satipo, Rio Satipo, 4 km down- stream from Satipo (latter locality at 11°16'S, 74°37'W), MUSM 8860, 1 (60.8). Provincia Satipo, Satipo, Rio Coviriali (11°16'S, 74°37'W), MUSM 8861, 1 (51.3). Provincia Satipo, Rio Ene basin, Rio Negro, MUSM 8862, 4 (38.0-51.23). Pasco: Provincia Oxampampa, Iscozacin, Rio Chuchurras, Villa America (approximately 10°04'S, 75°07'W), MUSM 8863, 13 (3, 36.4—49.6). Provincia Oxampampa, Rio Iscozacin, 39 km NNE of Oxampampa, LACM 37362-4, 2. Provincia Oxampampa, Quebrada Sachavaca, tributary of Rio Palcazu, MUSM 10761, 6. Huanuco: Provincia Pachitea, Rio San Ale- jandro, a tributary of Rio Sungarayacu, just above junction with Rio Sungarayacu (approximately 9°23'S, 75°11'W), FMNH 105273, 37 (formerly FMNH 84265, in part). Provincia Pachitea, Rio Llullapichis (=Yuyapichis), approximately 2 km upstream from mouth into Rio Pachitea (approximately 9°37'S, 74°57'W), ROM 55853, 11 (2, 47.4-^8.0). Provincia Pachitea, Rio Huambo, at its mouth in Rio Pachitea (approximately 9°36'S, 74°56'W), ROM 70107, 9. Cusco: La Convencion, Echarata Sagakiato, Quebrada Pagonpirintsi, USNM 358006, 6. La Convencion, Echarata Sagakiato, Quebrada Prokigiato, USNM 358005, 3. La Convencion, Echarata Sagakiato, Que- brada Tigonkavi, USNM 358003, 10. La Convencion, Echarata Sagakiato, Quebrada Matiariroate, USNM 358015, 12. La Convencion, Echarata Sagakiato, Quebrada Kemariatoi, USNM 358011, 2. La Convencion, Echarata Sagakiato, Que- brada Porocari, USNM 358007, 8. La Convencion, Echarata Sagakiato, Quebrada Otsitiari, USNM 358012, 1. La Conven- cion, Echarata Peruanita, Quebrada Igoripato, USNM 358002, 3. La Convencion, Echarata Shivangorani-Camisea, Quebrada Kapoparoari, USNM 358004, 20. La Convencion, Echarata Shivangorani-Camisea, Quebrada Kapiroshambia, USNM 358010, 14. La Convencion, Echarata Shivangorani-Camisea, Quebrada Songarinsiatoi, USNM 358009, 16. La Convencion, Echarata Malvinas, Quebrada Kamagatiniatoi, USNM 358014, 6. La Convencion, Echarata Malvinas, Quebrada Yaririato, USNM 358013, 2. La Convencion, Echarata Malvinas, Rio Urubamba, USNM 358008, 2. La Convencion, Echarata Par- vanita, Quebrada Kayonaroata, USNM 357992, 5. NUMBER 613 91 Creagrutus cochui Gery, 1964 FIGURES 33, 35, TABLE 14 Creagrutus cochui Gery, 1964:56, fig. 12 [type locality. Peru (Loreto), "Upper Amazon region surrounding Iquitos"]; 1977:393, 407 [species included in key, life photo].—Ortega and Vari, 1986:8 [Peru; common name].—Gery and Renno, 1989:5 [comparison with C. planquettei].—Vari and Howe, 1991:15 [holotype depository].—Roman-Valencia and Cala, 1996:148 [Co- lombia, Rio Loreto-Yacii, Rio Amazonas basin]. DIAGNOSIS.—The presence of a horizontally elongate, but distinct, main body of the humeral mark is unique to Creagru- tus cochui within the genus, being approximated only by larger specimens of C. atrisignum, an endemic of the Rio Tocantins basin. The latter species, however, has a secondary humeral mark situated dorsal to the horizontally elongate primary mark; this additional patch of dark pigmentation is absent in C. co- chui. Other features, which in combination separate C. cochui from the other members of the clade composed of Creagrutus and Piabina, are the possession of premaxillary dentition ar- ranged in the three components generalized for most of the spe- cies of Creagrutus and Piabina without a distinctly larger gap between the first and second teeth of the primary series, typi- cally 6 teeth in the primary premaxillary tooth row, 2 or 3 teeth on the maxilla, 5 teeth on each dentary, 38 to 41 lateral line scales without a lamellar process over each pore, 4 scale rows between the dorsal-fin origin and the lateral line, 9 or 10 pre- dorsal scales, 2 post-anal scales anterior to the anal-fin origin, 11 to 13 branched anal-fin rays, the head length (24.1%-26.5% of SL), the interorbital width (27.8%-32.5% of HL), the rela- tively shallow and transversely rotund body, the well-devel- oped third infraorbital contacting the horizontal limb of the preopercle, the lack of a series of midlateral dark marks on the body, the horizontally elongate humeral mark, and the absence of a discrete patch of dark pigmentation on the middle portions of the anterior dorsal-fin rays. DESCRIPTION.—Morphometric and meristic data for Crea- grutus cochui in Table 14. Greatest body depth at, or slightly anterior of, vertical through pelvic-fin insertion. Dorsal profile of head gently convex from tip of snout to vertical through pos- terior nostril, nearly straight from that point to tip of supraoc- cipital spine. Predorsal profile of body gently convex in all ex- amined specimens. Postdorsal profile of body straight to slightly convex. Ventral profile of head with obtuse angle at an- teroventral corner of dentary, straight from that point to isth- mus. Ventral profile of body convex, more so in larger individ- uals. Head obtusely pointed in both dorsal and lateral views. Up- per jaw longer than, and overhanging, lower jaw. Snout some- what fleshy. Papillae concentrated on anterior portion of snout and upper lip, particularly along ventral margin of lip and on folds and plicae extending between outer and medial premaxil- lary teeth. Lower lip fleshy anteriorly, with papillae concen- trated on dorsal surface. TABLE 14.—Morphometrics and meristics of Creagrutus cochui: (A) holotype of C. cochui, USNM 200426; and (B) all specimens of C. cochui from which counts and measurements were taken (n= 19). Standard length is expressed in mm; measurements 1 to 14=percentages of standard length; 15 to 18= percent- ages of head length. Dashes indicate values that could not be determined be- cause of damage to the holotype. Characters Standard length 1. Snout to anal-fin origin 2. Snout to pelvic-fin insertion 3. Snout to pectoral-fin insertion 4. Snout to dorsal-fin origin 5. Dorsal-fin origin to hypural joint 6. Dorsal-fin origin to anal-fin origin 7. Dorsal-fin origin to pelvic-fin insertion 8. Dorsal-fin origin to pectoral-fin insertion 9. Caudal peduncle depth 10. Pectoral-fin length 11. Pelvic-fin length 12. Dorsal-fin length 13. Anal-fin length 14. Head length 15. Postorbital head length 16. Snout length 17. Bony orbital diameter 18. Interorbital width Lateral line scales Scale rows between dorsal-fin origin and lateral line Scale rows between anal-fin origin and lateral line Predorsal median scales Branched dorsal-fin rays Branched anal-fin rays Branched pelvic-fin rays Pectoral-fin rays Vertebrae A B Morphometrics 68.3 64.1 46.0 24.0 43.3 59.0 32.4 24.4 29.1 11.4 - 15.6 - - 24.2 42.4 27.3 36.3 32.1 44.2-79.3 61.3-65.9 44.5-48.3 22.6-25.2 42.9^16.1 57.8-60.5 29.9-33.7 24.0-27.1 28.9-31.7 10.3-11.8 18.7-21.0 15.6-18.0 20.0-24.7 17.5-20.3 24.1-26.5 39.0-44.3 26.8-30.4 33.3-39.0 27.8-32.5 Meristics 39 4 3 9 8 13 7 13 37 38-41 4 3 9-10 8 11-13 7 12-14 37-39 Infraorbital series well developed. Anterior one-half of ven- tral margin of third infraorbital contacting horizontal limb of preopercle. Posterior margins of third to fifth infraorbitals not contacting vertical limb of preopercle, gap between posterior margins of infraorbitals and preopercle progressively decreas- ing dorsally. Premaxillary dentition in three series: primary row slightly curved, typically with 6 teeth, 5 teeth present on one premaxilla in one specimen, without pronounced gap between first and second tooth of series but with anterior teeth of contralateral series distinctly separated; triangular cluster of three tricuspi- date teeth; and single tooth of form similar to that of primary series lying lateral to fourth tooth of primary premaxillary se- ries. Maxilla with 2 or 3 tricuspidate teeth. Dentary with 5 teeth, first three teeth distinctly larger, with first and second teeth particularly large. Fourth tooth slightly smaller than third tooth. All teeth tricuspidate, with central cusp proportionally much larger on first three teeth and all cusps nearly equal on fifth tooth. 92 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY Dorsal-fin rays ii,8. Dorsal-fin origin slightly anterior to ver- tical through pelvic-fin insertion. Profile of distal margin of dorsal fin concave, more so in larger individuals. Anal-fin rays ii,11-13, rarely iii,12-13. Profile of distal margin of anal fin distinctly concave, with last branched and first 2 or 3 branched rays forming anterior lobe. Mature males with paired hooks present on posterior margins of main shaft of ray and on poste- rior branches of first through third branched rays; 1 or 2 hooks sometimes present on fourth ray. Pectoral-fin rays i, 11-13. Pectoral fin extending posteriorly approximately three-fourths of distance to pelvic-fin insertion. Pelvic-fin rays i,7. Mature males with hooks present on posterior margin of unsegmented and posterior main branch of segmented portions of all branched rays. Hooks also present on all branches except lat- eralmost branched pelvic-fin ray. Tip of pelvic fin extending posteriorly to anal-fin origin. Gill rakers 7-8+11-14. COLORATION IN LIFE.—(based on life photo of a paratype of the species in an aquarium, Gery, 1964, fig. 12a; 1977:393). Overall coloration of body brown with guanine highlights on scales, opercle, and infraorbitals. Horizontally elongate, dark humeral mark very obvious. Lighter patch of dark pigmenta- tion extending dorsally from main portion of humeral mark. Distal portion of anterior rays of dorsal fin apparently dark. Dark pigmentation present on basal portions of middle caudal- fin rays. Anterior margin of anal fin white. Light highlights present along rays of dorsal fin. COLORATION IN ALCOHOL.—Overall ground coloration tan. Smaller specimens with dorsal surface of brain covered by rel- atively large, dark chromatophores, this pigmentation obscured by thicker bones and surface pigmentation in larger individu- als. Dorsal surface of head with scattered, small, dark chro- matophores; chromatophore field more concentrated over snout, particularly anterior to nares where pigmentation forms discrete crescent. Posteroventrally inclined band of chromato- phores under anterior margin of adipose eyelid. Narrow band of dark chromatophores bordering ventral and posterior mar- gins of orbit in many Creagrutus species absent. Surface of fourth and fifth infraorbitals with scattered, small, dark chro- matophores. Distinct patch of large dark chromatophores on dorsal portion of opercle, sometimes also extending anteriorly onto posterior portion of infraorbital series; when well devel- oped chromatophore field forming horizontal dark band poste- rior of orbit. Dorsal and dorsolateral surfaces of body with scattered, small, dark chromatophores; chromatophore fields more con- centrated over center of scales. Midlateral dark stripe extending from supracleithrum to caudal-fin base. Humeral mark lying within midlateral stripe; main portion of mark consisting of horizontally elongate patch of dark pigmentation. Main portion of humeral mark flanked dorsally by very faint to moderately pigmented anterodorsally angled patch. Some specimens with limited area of scattered, dark chromatophores ventral of main body of humeral mark. Dorsal fin with interradial membranes between distal por- tions of last unbranched and anterior 4 to 6 branched rays with vertically elongate patches of dark pigmentation. Interradial pigmentation most intense between last unbranched and first branched and between first and second branched rays. Remain- der of dorsal fin with small dark chromatophores outlining rays. Anal fin ranging from hyaline to having distal portions of middle rays somewhat dusky. Caudal fin with variably appar- ent basal spot formed by chromatophores as large as, and con- tinuous with, those of midlateral stripe. Middle caudal-fin rays and associated membranes with scattered, dark chromato- phores, giving region dusky appearance. Pectoral and pelvic fins hyaline to slightly dusky. ECOLOGY.—Examination of the stomach contents of two specimens prepared for clearing and staining in this study re- vealed parts of seeds, larval and adult insects, and in one case a portion of the head of a small fish. In the southern portions of its range Creagrutus cochui was captured sympatrically with C. pi la within the Rio Neshuya, a tributary of the Rio Aguaytia (MUSM 8887 and 5240; MUSM 8885 and 8876, respectively). COMMON NAME.—Peru: "Majorita" (Ortega and Vari, 1986:8). DISTRIBUTION.—Creagrutus cochui occurs in the western portions of Amazon basin in Peru, Brazil, and perhaps Colom- bia (see below, under "Remarks," concerning latter locality; Figure 33, triangles). GEOGRAPHIC VARIATION.—The pigmentation in the region of the humeral mark in the samples (MUSM 8885, 8886, 8887) from the southern portion of the species' range in the Rio Aguaytia basin of the Department of Ucayali, Peru, differs sightly from that in samples from further to the north. The dark pigmentation situated dorsal of the main body of the humeral mark, which is faint in more northerly population samples, is more obvious in the Rio Aguaytia sample. The portion of the midlateral stripe contiguous with the humeral mark in the Rio Aguaytia sample also is more heavily pigmented than the re- mainder of the stripe and the humeral mark. This contrasts with the situation in populations further to the north in which the hu- meral mark and stripe are equally dark. Additional samples from intervening regions are necessary to determine whether this variation is significant. REMARKS.—One specimen from a Colombian location (UF 33678) may represent the most northerly record for this spe- cies. The specimen's poor condition precludes a definitive identification. MATERIAL EXAMINED.—149 specimens (19,44.2-79.3). BRAZIL. Amazonas: Rio lea, Igarape Boa Vista, MZUSP 28035, 53 (15, 44.2-73.9; 2 specimens cleared and counter- stained for cartilage and bone). Caiaua, Igarape da Cachoeira, along margin of Rio lea, MZUSP 17536, 3 (1, 79.3). Igarape Acu, 7 km below Santo Antonio do lea (3°O5'S, 40°49'W), MZUSP 17574, 63. Igarape tributary to Rio lea, 17.4 km downstream of Santo Antonio do lea, USNM 342927, 10. NUMBER 613 93 FIGURE 35.—Creagrutus cochui, MZUSP 28035, 65.5 mm SL; Brazil, Amazonas, Rio lea, Igarape Boa Vista. COLOMBIA. Meta: Roadside pond and stream 48 km NNE of Vistahermosa (Rio Guaviare basin), UF 36678, 1 (see under "Remarks," above, concerning this specimen). PERU. Loreto: Upper Amazon [Rio Amazonas], near Iqui- tos, USNM 200426, 1 (68.3, holotype of Creagrutus cochui); MHNG 2183.36, 1 (54.8, paratype of Creagrutus cochui). Que- brada Carahuayte at km 20 on road between Jenaro Herrera and Colonia Angamos, NRM 26306, 1; NRM 26307, 3 (1, 61.5). Rio Ampiyacu, near Pebas (3°20'S, 71°49'W), CAS 160723 (formerly SU 60723), 6. Ramon Castilla, Beirut, MUSM 194, 1. Ucayali: Provincia Padre Abad, Rio Tahuayo, km 72 on road from Pucallpa to Tingo Mario, MUSM 8887, 1. Provincia Cor- onel Portillo, Rio Aguaytia basin, Rio Neshuya (mouth of river at 8°17'S, 75°03'W), MUSM 8885, 3; MUSM 8886, 2. Creagrutus cracentis, new species FIGURES 33, 36, TABLE 15 DIAGNOSIS.—The presence of two distinct rows of premaxil- lary teeth, the very elongate, moderately sloping maxilla com- pared with the condition in most congeners, and the five me- dian scales between the posterior margin of the anus and the anal-fin origin distinguish Creagrutus cracentis from all con- geners with the exception of C. maxillaris, a species known from the upper portions of the Rio Negro and Rio Orinoco of northern Brazil and southern Venezuela and the upper Rio Ma- deira basin along the Bolivian-Brazilian border. These two spe- cies can be differentiated by the postorbital head-length (36.8%-38.0% of HL in C. cracentis versus 40.6%-46.8% of HL in C. maxillaris), the orbital width (37.0%-^0.0% of HL in C. cracentis versus 28.7%-34.6% of HL in C. maxillaris), and to a lesser degree on the pectoral-fin length (17.9%-20.0% of SL in C. cracentis versus 15.1%-18.2% of SL in C. maxil- laris). DESCRIPTION.—Morphometric and meristic data for Crea- grutus cracentis in Table 15. Overall appearance of head and body distinctly elongate compared to most congeners; elonga- TABLE 15.—Morphometrics and meristics of Creagrutus cracentis, new spe- cies: (A) holotype of C. cracentis, MCP 15213; and (B) paratypes of C. cra- centis (n=5). Standard length is expressed in mm; measurements 1 to 14= percentages of standard length; 15 to 18=percentages of head length. Characters Standard length 1. Snout to anal-fin origin 2. Snout to pelvic-fin insertion 3. Snout to pectoral-fin insertion 4. Snout to dorsal-fin origin 5. Dorsal-fin origin to hypural joint 6. Dorsal-fin origin to anal-fin origin 7. Dorsal-fin origin to pelvic-fin insertion 8. Dorsal-fin origin to pectoral-fin insertion 9. Caudal peduncle depth 10. Pectoral-fin length 11. Pelvic-fin length 12. Dorsal-fin length 13. Anal-fin length 14. Head length 15. Postorbital head length 16. Snout length 17. Bony orbital diameter 18. Interorbital width Lateral line scales Scale rows between dorsal-fin origin and lateral line Scale rows between anal-fin origin and lateral line Predorsal median scales Branched dorsal-fin rays Branched anal-fin rays Branched pelvic-fin rays Pectoral-fin rays Vertebrae A B Morphometrics 38.3 66.5 46.2 23.2 46.2 54.0 28.7 19.1 28.1 9.2 19.3 13.8 19.5 15.7 26.1 38.0 26.0 37.0 25.0 21.5-33.3 63.7-67.3 46.3-48.3 23.4-25.1 46.4-47.0 51.2-54.1 26.6-28.2 16.5-20.1 25.6-27.8 9.2-9.9 17.9-20.0 13.5-15.0 18.0-19.5 14.6-16.2 25.9-26.8 36.8-38.0 25.7-28.1 38.0-40.0 25.2-27.1 Meristics 39 4 3 9 8 10 7 14 37 39^*0 4 3 9 8 9-10 6-7 13-14 38-39 tion particularly pronounced in smaller paratypes. Greatest body depth at vertical through dorsal-fin origin. Dorsal profile of head smoothly rounded from margin of upper jaw approxi- mately to vertical through posterior nostril in specimens of all examined sizes; nearly straight from that point to rear of su- 94 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY FIGURE 36.—Creagrutus cracentis. new species, holotype, MCP 15213,38.3 mm SL; Brazil, Pari, Rio Tapajos, sandy beaches on island 5 km S of Itaituba (latter locality at 4° 17'S, 55°59'W). praoccipital spine. Interorbital region slightly convex or flat. Dorsal profile of body straight to slightly convex from tip of supraoccipital spine to dorsal-fin origin, barely angled at dor- sal-fin base. Ventral profile of head and body gently convex from isthmus to anal-fin origin. Head pointed anteriorly in lateral view and more so in dorsal view. Upper jaw slightly longer than, and slightly overhanging, lower jaw. Anterior portion of mouth nearly horizontal. Ventral margin of upper jaw gently curved and relatively longer than in all congeners with exception of Creagrutus maxillaris. Ante- rior surface of snout not as fleshy as in all congeners other than C. maxillaris; with numerous minute papillae over anterior sur- face. Papillae also along ventral margin of upper lip, dorsal margin of lower lip, and anterior and anterolateral surfaces of lower jaw. Plicae and fleshy flaps extending between outer and medial premaxillary teeth of most Creagrutus species absent. Lower lip not as fleshy anteriorly as in other Creagrutus spe- cies. Infraorbital series well developed. Third infraorbital well de- veloped, with ventral margin nearly in contact with horizontal limb of preopercle. Posterior margins of third through fifth in- fraorbitals nearly in contact with vertical limb of preopercle. Premaxillary dentition unusual for Creagrutus species, with only two distinct rows of teeth. Outer row consisting of 3 teeth arranged in slightly irregular series. First and third teeth of outer row unicuspidate, middle tooth with very weak lateral cusps. Inner tooth row on premaxilla consisting of 4 teeth, all with middle cusp distinctly more developed; medial and two lateral teeth tricuspidate, second tooth in series penticuspidate with very small lateral cusps. Elongate maxilla with 8 or 9 tri- cuspidate teeth with central cusp longer and typically some- what posteroventrally curved. Dentary teeth 10 to 12; anterior 3 teeth largest and following teeth progressively smaller. Two an- terior dentary teeth quadricuspidate, with second cusp dis- tinctly larger than others; third through ninth teeth tricuspidate, with central cusp stronger and varyingly posteriorly recurved; tenth through twelfth teeth conical (when 11 or 12 teeth present). Dorsal-fin rays ii,8. Dorsal-fin origin anterior to vertical through pelvic fin-insertion. Profile of distal margin of dorsal fin slightly concave. Anal-fin rays ii,9—10. Profile of distal margin of anal fin concave. Mature males with hooks on anal- fin rays limited to posterior margin of basal and middle seg- ments of the first and second branched rays. Pectoral-fin rays i, 12-13. Tip of pectoral fin reaching posteriorly approximately one-half of distance to pelvic-fin insertion. Pelvic-fin rays i,6,i or i,7. Larger mature males with hooks on all branched rays other than medialmost ray. Tip of pelvic fin extending posteri- orly approximately two-thirds of distance to anus. Gill rakers 6-7+10-11. COLORATION IN ALCOHOL.—Overall coloration light tan. Dorsal surface of head with superficial small dark chromato- phores. Surface of brain covered with larger, deep-lying, stel- late, dark chromatophores, latter pigmentation masked by thicker bones and adipose deposits in larger individuals. Snout and upper jaw with scattering of small, dark chromatophores slightly more concentrated anterior to nares. Scattered chro- matophores on lower jaw and on dorsal portions of opercle and infraorbital series. Distinct concentration of chromatophores anterior to nares and along ventral and posterior margins of or- bit present in other Creagrutus species not apparent in C. cra- centis. Lateral and dorsolateral portion of body with scattered chromatophores. Faint band formed by small dark chromato- phores on midlateral surface of body of smaller specimens; dis- tinction between midlateral band and dorsolateral pigmentation on body becoming increasingly obscure anteriorly with in- creasing size such that midlateral band is only discrete on pos- terior one-third of body in specimens of greater than approxi- mately 25 mm SL. Humeral mark vertically elongate, very slightly anteriorly concave, extending from slightly above hori- zontal through pectoral-fin insertion to approximately one scale width from dorsal midline. Pigmentation of humeral mark most intense in region centered along lateral line, variably less intense in its dorsal and ventral portions. Dorsal-fin ray margins and membranes with small dark chro- matophores. Basal portions of anterior branched anal-fin rays outlined by chromatophores. Caudal fin with dark horizontal stripe formed by superficial chromatophores over middle cau- dal-fin rays; stripe more intense basally. Stripe on middle cau- dal-fin rays flanked dorsally and ventrally by 2 or 3 relatively unpigmented rays. Remaining caudal-fin rays with few scat- tered, dark chromatophores; chromatophores somewhat more NUMBER 613 95 concentrated along ray margins. Pectoral and pelvic fins with only few scattered, small, dark chromatophores. ETYMOLOGY.—The specific name, cracentis, from the Latin for slender or graceful, refers to the slender body form of the species. ECOLOGY.—The type series was collected on a sandy beach in slow water current with no bottom or floating vegetation and limited vegetation along the shoreline. DISTRIBUTION.—Creagrutus cracentis is known only from the type locality in the lower portions of the Rio Tapajos (Fig- ure 33, star). COMPARISONS.—The only other Creagrutus species known from the Rio Tapajos basin is C. ignotus, which has been col- lected in the upper portions of that drainage basin. Creagrutus cracentis and C. ignotus differ in numerous features, most ob- viously in their dentition (see "Key to the Species of Creagru- tus in the Amazon Basin"). REMARKS.—This is one of the few records for a Creagrutus species proximate to the main channel of the lower portions of the Amazon River. MATERIAL EXAMINED.—6 specimens (5,21.5-38.3). HOLOTYPE.—BRAZIL. Para: Rio Tapajos, sandy beaches on an island located 5 km S of Itaituba (latter locality at 4°17'S, 55°59'W), collected by C.A.S. Lucena et al., 8 Dec 1991, MCP 15213, 1 (38.3). PARATYPES.—5 specimens (4, 21.5-33.3). BRAZIL. Para: Rio Tapajos, sandy beaches on an island lo- cated 5 km S of Itaituba (latter locality at 4°17'S, 55°59'W), collected with holotype, MCP 22018, 3 (2, 21.5-26.3; other specimen with damaged snout), USNM 353862, 2 (26.1-33.3; 1 specimen cleared and counterstained for cartilage and bone). Creagrutus crenatus, new species FIGURES 37,38, TABLE 16 DIAGNOSIS.—The combination of the possession of premax- illary dentition arranged in the three components generalized for most of the species of Creagrutus and Piabina without a distinctly larger gap between the first and second teeth of the primary series, 3 to 5 teeth on the maxilla, 6, very rarely 5, teeth in the primary tooth row of the premaxilla, 5 dentary teeth, 37 to 39 lateral line scales without a lamellar process over each pore, 8 to 11 predorsal median scales, 3 or 4 scale rows between the dorsal-fin origin and the lateral line, 2 post- anal scales to the anal-fin origin, 36 or 37 vertebrae, 10 to 12 branched anal-fin rays, the postorbital length (45.1%-50.4% of HL), the bony orbital diameter (25.2%-34.5% of HL), the in- terorbital width (31.3%-34.9% of HL), the poorly developed third infraorbital whose ventral margin falls distinctly short of the horizontal limb of the preopercle, the approximately equally wide gap between the posterior margins of the fourth through sixth infraorbitals and the vertical limb of the preoper- cle, the lack of a series of dark midlateral spots on the body, the bar-like, moderately elongate humeral mark, the absence of a TABLE 16.—Morphometrics and meristics of Creagrutus crenatus, new spe- cies: (A) holotype of C. crenatus, MHNLS 505; and (B) paratypes of C. crena- tus from which measurements and counts were taken (n= 11). Standard length is expressed in mm; measurements 1 to 14=proportions of standard length; 15 to 18=proportions of head length. Characters Standard length 1. Snout to anal-fin origin 2. Snout to pelvic-fin insertion 3. Snout to pectoral-fin insertion 4. Snout to dorsal-fin origin 5. Dorsal-fin origin to hypural joint 6. Dorsal-fin origin to anal-fin origin 7. Dorsal-fin origin to pelvic-fin insertion 8. Dorsal-fm origin to pectoral-fin insertion 9. Caudal peduncle depth 10. Pectoral-fin length 11. Pelvic-fin length 12. Dorsal-fm length 13. Anal-fin length 14. Head length 15. Postorbital head length 16. Snout length 17. Bony orbital diameter 18. Interorbital width Lateral line scales Scale rows between dorsal-fin origin and lateral line Scale rows between anal-fin origin and lateral line Predorsal median scales Branched dorsal-fin rays Branched anal-fin rays Branched pelvic-fin rays Pectoral fin rays Vertebrae A B Morphometrics 66.1 61.1 45.4 25.1 49.2 54.9 29.7 28.0 34.9 11.5 19.7 15.1 19.8 16.2 26.3 50.0 31.6 25.3 32.2 41.9-70.2 59.4-64.1 44.4-49.0 25.1-28.7 48.7-51.7 53.5-57.0 27.4-32.6 26.8-31.8 32.6-36.9 11.3-13.1 18.4-23.2 14.8-17.7 18.1-23.9 15.6-19.5 26.1-28.3 45.1-50.4 27.7-32.7 25.2-34.5 31.3-34.9 Meristics 37 4 4 11 8 12 6 12 37 37-39 3-* 4 8-11 8 10-12 6-7' 11-13 36-37 'Seven branched pelvic-fin rays less common. narrow middorsal line of dark pigmentation in the predorsal re- gion, and the absence of a discrete patch of dark pigmentation on the middle portion of the anterior dorsal-fin rays distin- guishes Creagrutus crenatus within the clade composed of Creagrutus and Piabina. DESCRIPTION.—Morphometric and meristic data for Crea- grutus crenatus in Table 16. Body moderately deep and com- pressed. Greatest body depth between 1 and 3 scale rows ante- rior of pelvic-fin insertion. Dorsal profile of head distinctly convex from margin of upper lip to vertical between nares, straight from that point to posterior tip of supraoccipital spine. Dorsal profile of body slightly and smoothly convex to dorsal- fin origin, straight from that point to caudal peduncle. Ventral profile of head with obtuse angle (shallow convexity in some specimens) approximately midway between margin of lower lip and posterior of dentary. Ventral profile of head and body slightly convex from that point approximately to pelvic-fin in- sertion; slightly concave from anal-fin origin to caudal pedun- cle. Most external surfaces of head covered with minute papil- 96 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY FIGURE 37.—Creagrutus crenatus, new species, holotype, MHNLS 505, 66.1 mm SL; Venezuela, Lara, Que- brada Sanare, in Yay (9°45'N, 69°43'W). lae. Upper jaw longer than, and overhanging, lower jaw. Anterior portion of snout quite fleshy, with many minute papil- lae continuing from upper lip into mouth on fleshy flaps be- tween premaxillary teeth. Lower lip distinctly fleshy anteriorly, inner surfaces of lower lip highly convolute. Infraorbital series poorly developed, with ventral margin of third infraorbital broadly separated from ventral limb of preo- percle. Posterior margin of third infraorbital distinctly sepa- rated from vertical limb of preopercle by space between one- third and one-half width of orbit; posterior and ventral margins of third infraorbital broadly rounded and with greater curvature than orbit. Posterior margins of fourth and fifth infraorbitals separated from vertical limb of preopercle by broad gap ap- proximately equal to width of fourth infraorbital. Premaxillary dentition in three series; primary row forming gentle curve with teeth all aligned with margin of premaxilla, typically with 6 teeth (S teeth present on only one premaxilla in 1 of 13 specimens examined for this feature) without pro- nounced gap between first and second teeth of series; all teeth rounded and tricuspidate with secondary cusps poorly devel- oped in fifth and sixth teeth; triad of three distinctly larger teeth with posterior teeth anteroposteriorly elongate and posterolat- eral tooth very large; and single tooth of form similar to that of primary series lying lateral to fourth tooth of primary series. Maxilla with 3 to 5 compressed, tricuspidate teeth. Dentary with five tricuspidate teeth; anterior two teeth largest, with sec- ond tooth only slightly higher, but obviously larger, than first tooth and more than twice as high as distinctly smaller third tooth. Remaining dentary teeth progressively decrease in size posteriorly. Dorsal-fin rays ii,8 in all specimens. Dorsal-fin origin lo- cated at, or slightly posterior to, vertical through pelvic-fin in- sertion. Distal margin of dorsal fin nearly straight, very slightly concave as result of slight elongation of first 2 or 3 rays. Anal- fin rays ii,10-12 or iii,10-12. Anal fin in mature males with hooks on segments of anterior 3 to 5 branched rays; hooks present on posterior unbranched ray in one specimen. Distal margin of anal fin nearly straight, anterior rays slightly elon- gate. Tip of pectoral fin approaching, or extending beyond, pel- vic-fin insertion, at most two scale rows separating tip of pec- toral fin from pelvic-fin base. Pelvic-fin rays typically i,6,i, less commonly i,7 (in 3 of 13 specimens); one specimen with 7 branched rays and medial unbranched ray. Tip of pelvic fin ap- proaching, or extending to, anal-fin origin. Pelvic-fin rays in mature males with hooks on medial and in some specimens medial and lateral surfaces of segmented and unsegmented por- tions of all rays medial of lateral unbranched element. Posterior margin of body scales undulate to crenate. This scale form most obvious in lateral line scales that tend to be smaller than immediately adjacent series of scales in both dor- sal and ventral directions. Gill rakers 5-7+ 7-12. COLORATION IN ALCOHOL.—Dorsal surface of head with diffuse pattern of small dark chromatophores most concen- trated on snout and over frontal portion of fontanel. Distinct small crescent of dark chromatophores present immediately in front of anterior nares. Thin dark longitudinal stripe between nares and dorsal midline extending anteriorly onto snout in some specimens. Band of scattered, dark chromatophores ex- tending from immediately lateral of nares posteroventrally un- der orbit, and continuing along ventral margin of orbit; band darkest and most concentrated along anteroventral portion of orbit, narrowing and continuing around posterior margin of or- bit. Lips and ventrolateral surface of head unpigmented; reflec- tive guanine well developed on opercle and cheek. Dark body pigmentation most concentrated dorsally, particularly along dorsal midline as diffuse longitudinal stripe; stripe darkest at dorsal-fin base, and in transverse band over center of exposed surface of scales. Humeral mark poorly developed, most con- centrated immediately dorsal of lateral line and becoming dif- NUMBER 613 97 FIGURE 38.—Map of central and northern South America showing geographic distribution of Creagrutus crena- tus (star, 1 =type locality), Creagrutus ephippiatus (triangle, 2=type locality), Creagrutus figueiredoi (squares, 3 =type locality), and Creagrutus flavescens (dots, 4=type locality) (some symbols represent more than one local- ity or lot of specimens). fuse and irregular two scale rows towards dorsum. Mark atten- uated ventrally and only present in second scale row below lateral line as scattered chromatophores. Dark pigmentation on lateral surface of body, other than for humeral bar, restricted to area dorsal of lateral line in some individuals, other specimens with pigmentation along posterior margins of scales above pec- toral fin. Region of body immediately dorsal of anal-fin base usually with 10 to 20 scattered chromatophores directly dorsal of anal-fin base. Smaller specimens (INHS 28851, 41.9-48.2 mm SL) showing concentration of chromatophores in associa- tion with bases of anterior anal-fin rays. Midlateral stripe be- coming denser and somewhat wider posteriorly on caudal pe- duncle where stellate chromatophores form broad triangular pigmented area. Smaller, better-preserved specimens showing concentration of reflective guanine in central portion of midlat- eral stripe. Caudal-fin rays all delineated by dark pigmentation most in- tense on central and ventral rays. Unbranched anal-fin rays un- pigmented except for small number of dark chromatophores near base, branched rays delineated by dark pigmentation; pig- mentation darkest on anterior margins of fin rays. Dorsal-fin membranes with dark chromatophores most concentrated on distal one-half of rays, unbranched rays darkly pigmented. Rays of lateral one-half of pectoral fin delineated by large chromatophores in large specimens; smaller specimens (INHS 28851) with few scattered chromatophores. Pelvic fin hyaline. ETYMOLOGY.—The species name, crenatus, from the Latin meaning notched or bearing rounded projections, is in refer- ence to the form of the exposed posterior margins of many of the scales. ECOLOGY.—One lot (INHS 28851) was collected in a clear rocky stream with considerable current. 98 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY DISTRIBUTION.—Creagrutus crenatus is known only from three collections that originated in the upper portions of the Rio Tocuyo, an isolated system that drains to the Caribbean Sea, Estado de Lara, north central Venezuela (Figure 38, star). COMPARISONS.—Creagrutus crenatus is similar to C. taphomi and C. lassoi, two species from the region immedi- ately to the east of the Rio Tocuyo system in northern Venezu- ela. These three species share a moderately deep body, 10 to 12 branched anal-fin rays, and a somewhat diffuse, slightly elon- gate humeral mark. Two of these species, C. crenatus and C. lassoi, share the distinctive features of undulate to crenate pos- terior scale margins and biuncinate pelvic-fin ray segments. Creagrutus crenatus is most similar to C. lassoi, especially with regard to meristics and fin-ray hook morphology. These two species differ in the straight posterior opercular margin in C. crenatus compared with the concave posterior opercular margin in C. lassoi, the modally higher number of branched anal-fin rays and lateral line scales in C. crenatus versus C. las- soi, and the crenate posterior scale margins, especially along the midlateral surface of the body in C. crenatus in comparison to the typically smooth scale margins in C. lassoi. MATERIAL EXAMINED.—13 specimens (13,31.0-70.2). HOLOTYPE.—VENEZUELA. Lara: Quebrada Sanare in Yay (9°45'N, 69°43'W), collected by "Yepez and Martin" (?=A. Fernandez-Yepez and F. Martin), 28 Dec 1954, MHNLS 505,1 (66.1). PARATYPES.—11 specimens (11,41.9-70.2). VENEZUELA. Lara: Quebrada Sanare in Yay (9°45'N, 69°43'W), collected with holotype, MHNLS 12900, 6 (55.9-70.2; 1 specimen cleared and counterstained for cartilage and bone). Rio Tocuyo drainage, Rio Curarigua, Puente Torres (10°12'N, 69°54'W), between Carora and Barquisimeto, col- lected by D.C. Taphorn et al., 6 Jan 1993, INHS 28851, 5 (41.9^8.2). NONTYPE SPECIMENS.—1 specimen (31.0). VENEZUELA. Lara: Rio Tocuyo drainage, Rio Curarigua, Paso San Antonio, Pozo (swamp) La Jaguara near Cuqurizzio, USNM 219617, 1(31.0). Creagrutus ephippiatus, new species FIGURES 38,39, TABLE 17 DIAGNOSIS.—The combination of the possession of premax- illary dentition arranged in the three components generalized for most of the species of Creagrutusand Piabina without a dis- tinctly larger gap between the first and second teeth of the pri- mary series, 6, occasionally 5, teeth in the primary series of each premaxilla, 3 or 4 maxillary teeth, 6, less commonly 7, teeth on each dentary, 10 to 12 predorsal median scales, 38 to 41 lateral line scales without a lamellar process over each pore, 4, rarely 5, scale rows between the dorsal-fin origin and the lat- eral line, 3 or 4 scale rows between the anal-fin origin and the lateral line, 10 or 11 branched anal-fin rays, 38 to 40 vertebrae, 6 or 7 gill rakers on the upper limb and 11 or 12 gill rakers on TABLE 17.—Morphometrics and meristics of Creagrutus ephippiatus, new spe- cies: (A) holotype of C. ephippiatus, MBUCV V-29068; and (B) paratypes of C. ephippiatus (n=34). Standard length is expressed in mm; measurements 1 to 14=percentages of standard length; 15 to 18=percentages of head length. Characters Standard length 1. Snout to anal-fin origin 2. Snout to pelvic-fin insertion 3. Snout to pectoral-fin insertion 4. Snout to dorsal-fin origin S. Dorsal-fin origin to hypural joint 6. Dorsal-fin origin to anal-fin origin 7. Dorsal-fin origin to pelvic-fin insertion 8. Dorsal-fin origin to pectoral-fin insertion 9. Caudal peduncle depth 10. Pectoral-fin length 11. Pelvic-fin length 12. Dorsal-fin length 13. Anal-fin length 14. Head length IS. Postorbital head length 16. Snout length 17. Bony orbital diameter 18. Interorbital width Lateral line scales Scale rows between dorsal-fin origin and lateral line Scale rows between anal-fin origin and lateral line Predorsal median scales Branched dorsal-fin rays Branched anal-fin rays Branched pelvic-fin rays Pectoral-fin rays Vertebrae A B Morphometrics 47.6 60.7 45.3 22.5 46.9 55.9 28.6 25.4 32.4 11.3 20.2 16.4 22.1 16.8 25.6 44.3 28.7 33.6 30.3 27.4-58.4 60.5-64.5 44.3^8.0 22.8-24.7 46.8-49.8 54.0-57.9 27.8-29.7 23.1-25.7 30.7-33.6 10.7-12.0 18.1-21.3 14.0-16.7 19.5-22.4 15.5-18.5 24.3-27.0 43.7-47.4 27.3-31.6 31.3-35.7 29.7-33.7 Meristics 39 4 3 10 8 11 7 12 38 38-41' 4-52 3 ^ 10-12 8 10-11 5-74 11-13 38-405 'Forty-two lateral line scales present in only 1 specimen. 2Five scale rows between dorsal-fin origin and lateral line present in only 3 paratypes. 3Four scale rows between anal-fin origin and lateral line present in only 2 paratypes. 4Five branched pelvic-fin rays present in only 1 paratype; 7 branched rays present only in larger paratypes. 'Forty vertebrate present in only 1 paratype. the lower limb of the first gill arch, the caudal peduncle depth (10.7%-12.0% of SL), the distance from the dorsal-fin origin to the anal-fin origin (27.8%-29.7% of SL), the distance from the dorsal-fin origin to the pelvic-fin insertion (23.1%-25.7% of SL), the distance from the dorsal-fin origin to the pectoral- fin insertion (30.7%-33.6% of SL), the postorbital head length (43.7%^t7.4% of HL), the interorbital width (29.7%-33.7% of HL), the contact between the ventral margin of the third in- fraorbital and the horizontal limb of the preopercle in larger specimens, the spot of dark pigmentation at the base of the middle caudal-fin rays, the vertically elongate, ventrally atten- uating humeral mark extending to the middorsal line, without a secondary, dorsal patch of pigmentation, the absence of a dis- tinct patch of pigmentation on the dorsal fin, the dark pigmen- NUMBER 613 99 HGURE 3V.—Creagrutus ephippiatus, new species, holotype, MBUCV V-29068, 47.6 mm SL; Venezuela, Ama- zonas, upper Rio Siapa, Campamento Siapa. tation on the basal portions of the middle caudal-fin rays, and the lack of a series of dark spots along the midlateral surface of the body distinguishes Creagrutus ephippiatus within the clade formed by Creagrutus and Piabina. DESCRIPTION.—Morphometric and meristic data for Crea- grutus ephippiatus in Table 17. Head and body moderately ro- bust, more so in anterior portion of body in larger specimens. Greatest body depth at, to slightly anterior of, dorsal-fin origin. Dorsal profile of head distinctly convex from margin of upper lip to vertical through posterior nostril, slightly convex from that point to tip of supraoccipital spine; convexity in this region less pronounced in larger individuals. Interorbital region trans- versely rounded. Dorsal profile of body slightly convex from tip of supraoccipital spine to dorsal-fin origin, but without dis- tinct change in alignment relative to dorsal profile of head. Dorsal surface of body with obtuse middorsal ridge; ridge more obvious posteriorly. Ventral profile of head with obtuse angle at anteroventral corner of dentary, angle variably obvious; profile slightly convex from angle to isthmus. Prepelvic profile of body slightly convex in smaller individuals, somewhat more convex in some larger specimens. Prepelvic region of body transversely rounded. Head obtusely pointed in lateral view, somewhat more com- pressed in dorsal view. Upper jaw somewhat longer than, and overhanging, lower jaw. Anterior of snout, particularly antero- medial portion with numerous papillae. Papillae more concen- trated on fleshy upper lip, especially along ventral lip margin and on folds and plicae extending between outer and medial premaxillary teeth. Lower lip with numerous papillae on dorsal surface and scattered papillae anteriorly. Infraorbital series well developed in all specimens larger than about 30 mm SL, with ventral margin of third infraorbital falling slightly short of horizontal limb of preopercle in smaller specimens, but contacting that bone in larger individuals. Pos- terior margins of third through fifth infraorbitals distinctly sep- arated from vertical limb of preopercle in all specimens; gap decreasing proportionally ontogenetically, but still distinct in larger individuals. Premaxillary dentition in three series: primary series sig- moid, with 6, occasionally 5, tricuspidate teeth, without pro- nounced gap between first and second tooth of series but with medial tooth separated from matching tooth of contralateral se- ries by distinct gap; triangular cluster of 3 teeth, larger than those of primary series; and single tooth of form similar to that of primary series occurring lateral to fourth tooth of primary series or in the region slightly anterolateral to area of contact of third and fourth teeth of primary premaxillary row. Maxilla with 3 or 4 tricuspidate teeth, 3 teeth typically present in smaller individuals. Dentary with 6, less commonly 7, tricuspi- date teeth, with seventh tooth, when present, having barely ap- parent cusps; second tooth more massive than and about one- fourth longer than first tooth; second tooth about 1.5 times as high as third tooth; third tooth twice as high as fourth tooth; fourth through sixth or seventh teeth progressively smaller. Dorsal-fin rays ii,8 in all specimens. Dorsal-fin origin ap- proximately at vertical through pelvic-fin insertion. Profile of distal margin of dorsal fin slightly concave. Anal-fin rays iii,10-11 or ii,10. Profile of distal margin of anal fin concave. Mature males with hooks on distal margins of first 4 or 5 branched anal-fin rays, and occasionally on last unbranched ray; number of hooks decreasing posteriorly and progressively limited to increasingly more distal portions of fin ray. Pectoral- fin rays i,10-12, typically i,l 1. Tip of pectoral fin falling 1 to 2 scales short of pelvic-fin insertion. Pelvic-fin rays i,5-6,i or i,7; typically i,6,i; i,7 in some larger specimens. Tip of pelvic fin falling 1 to 2 scales short of anal-fin origin. Mature males with hooks on all branched pelvic-fin rays, including medial ray, if branched, and sometimes on medial ray when unbranched; hooks, when present on medial unbranched ray, usually less dense than those on branched rays. Gill rakers 6-7+11-12. COLORATION IN ALCOHOL.—Ground coloration tan. Dorsal surface of head in smallest specimens with dense pigmentation 100 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY overlying brain and scattered, dark chromatophores on snout. Specimens greater than 30 mm SL with entire dorsal surface of head covered with dense field of small, dark chromatophores extending anteriorly to margin of upper lip and posteriorly to anterior margin of orbit. Density of chromatophore field some- what less on upper lip in some individuals. Region anterior to nostrils with pigmentation somewhat more intense, forming distinct crescent-shaped patch in smaller specimens; patch not apparent in medium-sized to larger individuals. Smaller indi- viduals with narrow band of dark pigmentation extending from under nostrils to region anteroventral or ventral of orbit; band subsumed into overall darker pigmentation in that region in larger specimens. Region posterior to orbit along with dorsal portion of opercle with scattered, dark chromatophores in smaller specimens, chromatophore field expanding further ven- trally and somewhat more dense, especially along posterior margin of orbit in larger individuals. Scales of posterolateral surface of body with series of dark chromatophores along posterior margin in smaller individuals; chromatophore field becoming progressively wider in larger individuals, but with basal portions of scales lacking chromato- phores and forming regular pattern of lighter colored regions. Humeral mark obvious and vertically elongate in specimens of all sizes. Mark comma-shaped and limited to lateral portion of body in smaller individuals, midlaterally centered main body darkest with anterior arching patch of more diffuse dark chro- matophores extending dorsally from its dorsal portion of dorsal midline. Contralateral humeral marks meet middorsally and form horizontally elongate dark middorsal stripe that extends about 3 scales along predorsal region; stripe extending approx- imately one scale posterior of margin of humeral mark. Main portion of mark becoming more intensely pigmented and verti- cally elongate with increasing size. Humeral mark extending ventrally by more diffuse, typically ventrally tapering patch of chromatophores; in largest specimens humeral mark extending to about one scale dorsal of horizontal through pectoral-fin in- sertion. Middorsal scales posterior to humeral marks with patches of dark pigmentation in larger specimens. Dark midlat- eral stripe limited to posterior two-thirds of body, pigmentation more intense posteriorly. Midlateral stripe merging anteriorly into overall dark pigmentation on lateral surface of the body in larger individuals. Dorsal fin with first unbranched ray and distal portions of second unbranched rays covered with dark stellate chromato- phores. Membranes of all but one or two posteriormost branched fin rays with dispersed, dark, irregularly shaped chro- matophores. Chromatophore field becoming progressive shorter on distal portions of successive fin membranes. Distal portion of second and third unbranched and first and some- times second branched anal-fin rays unpigmented; otherwise fin rays outlined by small dark chromatophores, with scattered chromatophores on intervening portions of fin membranes. Middle caudal-fin rays more intensely pigmented than rest of fin, with remaining fin rays outlined, to varying degrees, by small dark chromatophores. Pectoral and pelvic fins hyaline, or with some scattered, small, dark chromatophores in larger specimens. ETYMOLOGY.—The specific name, ephippiatus, from the Latin, ephippium, meaning saddle, refers to the saddle-like hu- meral marks that meet along the dorsal midline. ECOLOGY.—One of the nontype lots (AMNH 93144) was collected on a small sandy beach over a sand and mud bottom with detritus. A second lot (AMNH 93147) was captured at the upper end of rapids in the Rio Siapa over a gravel and boulder bottom. COMPARISONS.—Creagrutus ephippiatus is somewhat simi- lar to C. provenzanoi of the Rio Cataniapo, a tributary of the upper Rio Orinoco. The two species can, however, be distin- guished on the basis of the more arcuate dorsal portion of the humeral mark that extends further dorsally in C. ephippiatus compared to the mark in C. provenzanoi, the number of rows of scales above the lateral line (4, rarely 5, in C. ephippiatus ver- sus 5, rarely 4, in C. provenzanoi), and less discretely in the distance from the snout to the pectoral-fin insertion (22.5%-24.7% of SL versus 24.4%-27.3% of SL, respec- tively). Creagrutus ephippiatus is rather similar in terms of overall meristics and morphometrics to C. magoi of the central por- tions of the Rio Orinoco basin. The species differ, however, in overall body form that is best reflected in the distance from the dorsal-fin origin to the anal-fin origin (27.8%-29.7% of SL in C. ephippiatus versus 29.2%-33.8% of SL in C. magoi), details of dark pigmentation (form of humeral mark and pigmentation of middle caudal-fin rays). The species also have a pronounced modal shift in the number of total vertebrae (C. ephippiatus: 38 (34), 39(10), 40(1) versus C. magoi: 36(6), 37(38), 38(2)). DISTRIBUTION.—Creagrutus ephippiatus is only known from the Rio Siapa, a southern tributary of the Rio Casiquiare, upper Rio Negro basin, in southern Amazonas State, Venezuela (Figure 38, triangle), and is the only member of the genus known from that river system. MATERIAL EXAMINED.—56 specimens (35, 27.4-58.4). HOLOTYPE.—VENEZUELA. Amazonas: Upper Rio Siapa, Campamento Siapa (Siapa Base Camp), collected by R. Roy- ero et al., 26 Mar 1988, MBUCV V-29068,1 (47.6). PARATYPES.—34 specimens (34,27.4-58.4). VENEZUELA. Amazonas: Upper Rio Siapa, Campamento Siapa (Siapa Base Camp), collected with holotype, MBUCV V-29069, 24 (27.4-51.0); MBUCV V-18623, 3 (33.9-58.4); USNM 355116, 7 (33.3-47.0; 2 specimens cleared and coun- terstained for cartilage and bone). NONTYPE SPECIMENS.—21 specimens. VENEZUELA. Amazonas: Upper Rio Siapa, below Camp 1, MBUCV V-19187, 4. Upper Rio Siapa, at Siapa Base Camp, small beach on right bank, AMNH 93144, 13. Upper Rio Siapa, Yanomani Village, upper end of rapids on left bank, AMNH 93147,4. NUMBER 613 101 Creagrutus figueiredoi, new species FIGURES 38,40, TABLE 18 DIAGNOSIS.—The combination of the possession of premax- illary dentition arranged in the three components generalized for most of the species of Creagrutus and Piabina without a distinctly larger gap between the first and second teeth of the primary series, 2 or 3 teeth on the maxilla, 5 teeth in the pri- mary tooth row of the premaxilla, 5 or 6 dentary teeth, 36 to 38 lateral line scales without a lamellar process over each pore, 8 to 11 predorsal scales, 4 scale rows between the dorsal-fin ori- gin and the lateral line, 35 to 37 vertebrae, 9 or 10 branched anal-fin rays, 2 post-anal median scales to the anal-fin origin, the distance from the snout to the pectoral-fin insertion (22.6%-26.6% of SL), the distance from the snout to the anal- fin origin (31.4%—33.6% of SL), the distance from the dorsal- fin origin to the pectoral-fin insertion (30.6%-34.0% of SL), the postorbital head length (41.2%-45.1% of HL), the snout length (28.3%-33.1% of HL), the bony orbital diameter (33.6%-38.1% of HL), the dorsal-fin length (19.4%-22.3% of SL), the anal-fin length (15.6%-18.5% of SL), the caudal pe- duncle depth (11.2%-12.6% of SL), the well-developed third infraorbital approaching, but not contacting, the horizontal limb of the preopercle, the lack of a series of dark midlateral spots on the body, the discrete, wide, vertically elongate hu- meral mark shaped like an inverted comma, and the absence of a discrete patch of dark pigmentation on the middle portion of the anterior dorsal-fin rays distinguishes Creagrutus figueire- doi within the clade composed of Creagrutus and Piabina. DESCRIPTION.—Morphometric and meristic data for Crea- grutus figueiredoi in Table 18. Head moderately robust at all sizes. Body becoming increasingly robust anteriorly with in- creasing size. Greatest body depth at vertical through dorsal-fin origin in smaller specimens, at that point or shifted somewhat anteriorly in larger individuals. Dorsal profile of head gently convex from margin of upper lip to vertical through posterior nostril, straight from that point to tip of supraoccipital spine in smaller specimens, becoming slightly convex in larger individ- TABLE 18.—Morphometrics and meristics of Creagrutus figueiredoi, new species: (A) holotype of C. figueire- doi, MZUSP 50542; (B) paratypes of C. figueiredoi (n=27); and (C) nontype specimens of C. figueiredoi from Rio Araguaia basin, USNM 342235 (n=2). Standard length is expressed in mm; measurements 1 to 14=percent- ages of standard length; 15 to I8=percentages of head length. Characters Standard length 1. Snout to anal-fin origin 2. Snout to pelvic-fin insertion 3. Snout to pectoral-fin insertion 4. Snout to dorsal-fin origin 5. Dorsal-fin origin to hypural joint 6. Dorsal-fin origin to anal-fin origin 7. Dorsal-fin origin to pelvic-fin insertion 8. Dorsal-fin origin to pectoral-fin insertion 9. Caudal peduncle depth 10. Pectoral-fin length 11. Pelvic-fin length 12. Dorsal-fin length 13. Anal-fin length 14. Head length 15. Postorbital head length 16. Snout length 17. Bony orbital diameter 18. Interorbital width Lateral line scales Scale rows between dorsal-fin origin and lateral line Scale rows between anal-fin origin and lateral line Predorsal median scales Branched dorsal-fin rays Branched anal-fin rays Branched pelvic-fin rays Pectoral-fin rays Vertebrae A 63.3 65.4 47.1 23.5 46.1 59.7 33.1 28.0 32.1 12.4 19.7 16.4 20.2 18.6 26.1 44.2 30.9 34.5 30.3 38 4 3 9 8 10 7 13 36 B Morphometrics 37.6-55.5 60.8-65.6 44.2^18.2 22.6-26.6 44.6-48.1 55.8-59.9 31.4-33.5 25.5-27.8 30.6-32.8 11.2-12.6 18.4-20.5 14.6-17.3 19.4-21.8 16.6-18.5 24.2-27.1 41.2-45.1 28.3-33.1 33.6-38.1 29.6-34.3 Meristics 36-38 4 3 8-11 8-9' 9-10 6-7 12-14 35-37 C 41.7-52.1 64.5-64.9 47.4 22.8-24.3 46.8-47.0 55.8-58.3 33.1-33.6 28.7-29.6 32.6-34.0 11.7-12.2 19.4 15.6-15.9 21.6-22.3 15.6-17.5 25.2-27.5 42.9^4.1 28.2-29.4 33.8-38.1 29.7-30.1 38 4 3 9-10 8 10: 6 13 35 'Nine branched dorsal-fin rays present in only 1 paratype. 2Anal-fin ray count uncertain in one specimen with damaged anal fin. 102 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY uals. Interorbital region distinctly convex. Dorsal profile of body very slightly convex, without evident change in align- ment relative to that of head in smaller specimens, convex with distinct change in alignment relative to that of head in larger in- dividuals. Predorsal surface of body somewhat flattened trans- versely in region of supraoccipital spine; with middorsal ridge proximate to dorsal-fin origin in larger specimens. Ventral pro- file of head with distinct obtuse angle at anteroventral corner of dentary, straight or gently curved from that point to isthmus. Ventral profile of body very slightly convex in smaller speci- mens, more so in larger individuals. Prepelvic region of body obtusely flattened transversely. Head obtusely pointed in lateral and dorsal views. Upper jaw distinctly longer than, and overhanging, lower jaw. Snout not very fleshy, with few scattered papillae anteromedially. Papil- lae more concentrated along fleshy margins of lips and particu- larly on fleshy folds and plicae extending between outer and medial premaxillary teeth. Lower lip moderately fleshy anteri- orly, with numerous papillae along dorsal margin and with scattered papillae anteromedially. Infraorbital series well developed. Ventral margin of third in- fraorbital approaching, but falling slightly short of, horizontal limb of preopercle even in larger specimens. Posterior margins of third through fifth infraorbitals falling short of vertical limb of preopercle. Premaxillary dentition in three series: primary row curved, consisting of 5 teeth, occasionally with gap between third and fourth teeth but without gap between first and second teeth of series and with medial tooth of primary series separated from anterior tooth of contralateral series by distinct gap; triangular cluster of 3 larger teeth with posterolateral tooth largest; and single tooth of form similar to that of primary series situated lateral to space between third and fourth teeth of primary pre- maxillary row. Maxilla with 2 or 3 tricuspidate teeth. Dentary with 5 or 6 teeth; first two teeth subequal and distinctly larger than third; third tooth, in turn, much larger than fourth and fifth teeth. Dentary teeth all tricuspidate (when 5 teeth present) or last tooth conical (when 6 teeth present). Central cusp very well developed proportionally in first through third teeth, less so in fourth and fifth teeth. Dorsal-fin rays ii,8-9. Dorsal-fin origin anterior to vertical through pelvic-fin insertion. Profile of distal margin of dorsal fin slightly concave. Anal-fin rays ii,9-10. Profile of distal margin of anal fin distinctly concave, with last unbranched and anterior branched rays forming distinct lobe. Mature males with hooks present on first and second branched anal-fin rays and occasionally on second unbranched anal-fin ray. Pectoral- fin rays i,l 1-13. Tip of pectoral fin extending posteriorly ap- proximately three-fourths of distance to pelvic-fin insertion. Pelvic-fin rays i,6,i or i,7. Tip of pelvic fin extending posteri- orly approximately to anus. Mature males with hooks present on all branched anal-fin rays. Gill rakers 6-7+10-11. COLORATION IN ALCOHOL.—Overall ground coloration tan. Dorsal surface of head with scattered surface chromatophores overlying more concentrated chromatophores located on mem- branes of brain. Surface chromatophores more concentrated on snout and in region between and anterior to nostrils. Region immediately anterior to nostrils without more concentrated re- gion of chromatophores forming dark crescent-shaped patch as in many congeners, or patch barely apparent in some speci- mens. Series of dark chromatophores extending posteroven- trally from under nostrils to join curved band of chromato- phores along ventral and posterior borders of orbit. Scattered, dark chromatophores on postorbital portion of head located on dorsal one-half to two-thirds of infraorbital series and opercle. Scales of dorsolateral and dorsal portions of body with dark chromatophores concentrated along distal margin and on basal section of exposed portion of scale, scale pigmentation most in- tense on dorsal region of body. Diffuse midlateral stripe formed by dark surface chromatophores extending from slightly poste- rior of humeral mark to posterior portion of caudal peduncle, somewhat more concentrated posteriorly in some individuals. Humeral mark vertically elongate, with densely pigmented por- tion immediately dorsal of lateral line. Diffuse, ventrally atten- uating series of chromatophores extending slightly ventral of densely pigmented portion of mark. Dorsal portion of humeral mark consisting of variably shaped, vertically elongate patch of chromatophores extending one and one-half to two scales dor- sal of dark central portion of mark. Dorsal portion of mark ranging from distinctly lighter than central portion of mark to nearly as dark as that region. Anterior margin of mark ranging from straight to distinctly concave. Dorsal fin with unbranched rays outlined by dark chromato- phores, and distal two-thirds of membranes of anterior 4 or 5 rays with numerous larger chromatophores. Anal fin with ante- rior margins of first 4 to 7 rays variably outlined with chro- matophores and with scattered chromatophores on distal por- tions of membranes of anterior rays. Caudal-fin rays variably outlined with chromatophores, giving fin overall dusky appear- ance. Pelvic fin mostly hyaline. Pectoral-fin rays variably de- limited by small dark chromatophores. ETYMOLOGY.—The species name, figueiredoi, is in honor of Jose Lima de Figueiredo, Museu de Zoologia of the Univer- sidade de Sao Paulo, in recognition of his contributions to South American ichthyology and of his assistance to the senior author over the years. ECOLOGY.—The type locality is an upland river, approxi- mately 30 m wide, with fast to moderate flowing, moderately turbid water, over a rocky and sand bottom. In the upper Rio Araguaia basin Creagrutus figueiredoi has been captured to- gether with C. menezesi and C. seductus. During the filling of the Serra da Mesa reservoir in the upper Rio Tocantins basin, congeners collected with C. figueiredoi along the developing lake margin were C. menezesi and C. saxatilis. NUMBER 613 103 FIGURE 40.—Creagrutus figueiredoi. new species, holotype, MZUSP 50542, 63.3 mm SL; Brazil, Distrito Fed- eral, Rio Maranhao, approximately 35 air km N of Brasilia (approximately 15°32'S, 47°49'W). DISTRIBUTION.—Creagrutus figueiredoi occurs in the Rio Tocantins drainage system in both the upper Rio Tocantins and Rio Araguaia basins (Figure 38, squares). GEOGRAPHIC VARIATION.—The majority of the available specimens of C. figueiredoi come from the type locality in the Rio Maranhao basin of the Rio Tocantins system in the region of the type locality (Figure 38, square indicated by 3). Five specimens were collected approximately 400 river km to the north of the type locality along the margins of the Serra da Mesa reservoir in the upper Rio Tocantins during the filling of the impoundment (MNRJ 17334, 17339). These specimens fit within the range of variation for meristic and morphometric values for species from the holotype locality and are designated as paratypes (Table 18). Two specimens from the Municipio de Barra do Garcas, in the upper portions of the Rio Araguaia (USNM 342235) are tentatively identified as C. figueiredoi and are the only known specimens of the species from that portion of the greater Rio Tocantins basin. The Rio Araguaia sample differs from the up- per Rio Tocantins samples in proportional values reflecting the depth of the body (dorsal-fin origin to pelvic-fin insertion, dor- sal-fin origin to pectoral-fin insertion; Table 18, numbers 7 and 8) and to a lesser degree in the length of the dorsal-fin (Table 18, number 12). Furthermore, the two specimens from the Rio Araguaia have 35 vertebrae. Although this count falls within the range for specimens of upper Rio Tocantins basin (35 to 37 vertebrae), 35 vertebrae are relatively rare in available speci- mens from the upper Rio Tocantins (frequency of vertebrae in C. figueiredoi samples from that region: 35 (3), 36 (21), 37 (3)). The Rio Araguaia sample is limited to two specimens, and both individuals are apparently ripe females with expanded ab- domens. Such increased proportional body depth would ac- count for the greater relative dorsal-fin origin to pelvic-fin in- sertion distance and would partially contribute to the increased proportional dorsal-fin origin to pectoral fin insertion distance found in this sample in comparison to the samples from the up- per Rio Tocantins. Furthermore, more than 2500 river km sepa- rate the collection locality of the two specimens from the Rio Araguaia from the nearest known locality for C. figueiredoi in the upper Rio Tocantins basin. Intraspecific geographic varia- tion in meristic and morphometric values is often the case across such great distances and is found at shorter geographic distances in other Creagrutus species. Thus, the differences in proportional distance from the dorsal-fin origin to the pectoral- fin insertion and the relative length of the dorsal-fin between the Rio Araguaia and upper Rio Tocantins samples are possibly a function of a clinal shift in these features across the range of a single species. Shifts in modal vertebral counts also occur intraspecifically within various Creagrutus species (e.g., C. flavescens) and other characiforms (e.g., Ctenolucius beani and Boulengerella maculata, Vari, 1995:55, 66), which suggests that the modal shift in vertebral counts between population samples from the upper Rio Tocantins and the limited Rio Araguaia sample is a function of their geographic separation. Other recently ana- lyzed species (e.g., Pituna compacta; see Costa, 1998:147) have similar disjunct known distributions between the upper portions of the Tocantins and Araguaia basins. Given these fac- tors, and the massive gap in the known distribution of the spe- cies, we tentatively identify the Rio Araguaia samples as C. figueiredoi. Further samples from the upper Rio Araguaia and throughout intervening localities in the greater Rio Tocantins basin are necessary to resolve whether such variation should be recognized taxonomically. MATERIAL EXAMINED.—33 specimens (33,37.6-63.3). HOLOTYPE.—BRAZIL. Distrito Federal: Rio Maranhao, up- per Rio Tocantins basin, approximately 35 air km N of Brasilia (approximately 15°32'S, 47°49'W), collected by W.C. Starnes et al., 14 Nov 1984, MZUSP 50542, 1 (63.3). PARATYPES.—27 specimens (27, 37.6-55.5). 104 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY BRAZIL. Distrito Federal: Rio Maranhao, upper Rio To- cantins basin, approximately 35 air km N of Brasilia (approxi- mately 15°32'S, 47°49'W), collected with holotype, MZUSP 50543, 9 (40.2-53.1); MNRJ 14482, 2 (42.8-49.6); USNM 292221, 11 (40.1-55.5). Goids: Minacu/Colinas do Sul, Rio Tocantins, pools formed below the dam of Usina Hidroelectica (UHE) de Serra da Mesa after closure of dam to fill, collected by D.F. Moraes et al., 28 Oct to 3 Nov 1996, MNRJ 17334, 2 (38.8-52.2); MNRJ 17339, 3 (37.6-48.6). NONTYPE SPECIMENS.—5 specimens (5,41.7-63.0). BRAZIL. Distrito Federal: Rio Maranhao, upper Rio To- cantins basin, approximately 35 air km N of Brasilia (approxi- mately 15°32'S, 47°49'W), USNM 292221, 3 (60.7-63.0; specimens cleared and counterstained for cartilage and bone). Mato Grosso: Municipio de Barra do Garcas, Corrego Fundo (approximately 15°53'S, 52°15'W), USNM 342235, 2 (41.7-52.1; see comments under "Geographic Variation," above, concerning this lot). Creagrutus flavescens, new species FIGURES 38,41, TABLE 19 Creagrutus muellen[not of Gunther, 1859].—Boulenger, 1887:281 [misidenti- fication] [Ecuador (Pastaza) Canelos]. Creagrutus amoenus. Fowler, 1943a:239 [in part, only one of three paratypes; Colombia, (Caqueta), Rio Ortuguasa (Orteguaza), Florencia]. Creagrutus beni [not of Eigenmann, 1911].—Saul, 1975:106 [misidentifica- tion] [specimens from Ecuador, Napo (now in Sucumbios), Rio Aguarico, at Santa Cecilia]. DIAGNOSIS.—The combination of the possession of premax- illary dentition arranged in the three components generalized for most of the species of Creagrutus and Piabina without a distinctly larger gap between the first and second teeth of the primary series, 2 or 3 teeth on the maxilla, 6 teeth in the pri- mary tooth row of the premaxilla, 5 teeth on each dentary, 37 to 40 lateral line scales without a lamellar process over each pore, 9 or 10 predorsal median scales, 4 scale rows between the dor- sal-fin origin and the lateral line, 36 to 39 vertebrae, 9 to 12 branched anal-fin rays, 2 post-anal median scales to the anal- fin origin, the well-developed third infraorbital contacting the horizontal limb of the preopercle in larger specimens, the dis- tance from the dorsal-fin origin to the pelvic-fin insertion (3O.O%-35.1% of SL), the distance from the dorsal-fin origin to the anal-fin origin (34.4%-40.4% of SL), the distance from the dorsal-fin origin to the pelvic-fin insertion (30.0%-35.1% of SL), the distance from the dorsal-fin origin to the pectoral- fin insertion (32.0%-36.6% of SL), the caudal peduncle depth (11.5%-13.7% of SL), the dorsal-fin length (22.8%-26.5% of SL), the postorbital head length (38.3%-45.5% of HL), the bony orbital diameter (33.3%-^0.6% of HL), the lack of a se- ries of dark midlateral spots on the body, the possession of a discrete, vertically elongate, anteriorly curved humeral mark, the absence of a distinct dark spot on the basal portions of the caudal fin, and the absence of a discrete patch of dark pigmen- tation on the middle portion of the anterior dorsal-fin rays dis- tinguishes Creagrutus flavescens from all species within the clade composed of Creagrutus and Piabina with the exception of C. ignotus. These two species can be distinguished by the distance from the dorsal-fin origin to the hypural joint (55.5%-61.9% of SL C. flavescens versus 53.3%-55.4% of SL in C. ignotus), the distance from the dorsal-fin origin to the anal-fin origin (34.4%-40.4% of SL versus 26.9%-30.5% of SL, respectively), the distance from the dorsal-fin origin to the pelvic-fin insertion (30.0%-35.1% of SL versus 21.5%-25.4% of SL, respectively), the distance from the dorsal-fin origin to the pectoral-fin insertion (32.0%-36.6% of SL versus 28.5%-30.7% of SL, respectively), and the caudal peduncle depth (11.5%-13.7% of SL versus 9.3%-10.7% of SL, respec- tively). DESCRIPTION.—Morphometric and meristic data for Crea- grutus flavescens in Table 19. Head and body moderately ro- bust, with body deep. Greatest body depth at dorsal-fin origin in individuals up to 50 mm SL, located at that point or shifted somewhat anteriorly in larger specimens, particularly those with distended abdomens. Dorsal profile of head moderately convex from margin of upper lip to point slightly anterior of vertical through anterior nostril; nearly straight from that point to tip of supraoccipital spine. Predorsal profile of body continu- ing that of head and straight to slightly convex in smaller spec- imens. Dorsal profile notably convex, with distinct change in alignment relative to that of head in larger individuals. Predor- sal surface of body with distinct median ridge proximate to dorsal-fin origin, ridge more prominent in larger individuals. Ventral profile of head with distinct obtuse angle at anteroven- tral corner of dentary, nearly straight from that angle to isthmus at all sizes. Prepelvic region of body slightly convex in smaller specimens, more curved in larger individuals, being notably convex from populations in the Peruvian lowlands (see com- ments concerning these populations under "Remarks," below); indistinctly flattened transversely in specimens larger than 30 mm SL. Caudal fin with scales extending onto basal portions of each lobe in larger specimens. Head obtusely pointed in lateral view, somewhat laterally compressed in dorsal view. Upper jaw longer than, and slightly overhanging, lower jaw. Snout slightly fleshy anteromedially, with papillae on ventral margin of upper lip and on plicae and folds extending between outer and medial premaxillary teeth. Papillae concentrated along margin of upper lip. Infraorbital series well developed. Ventral margin of third in- fraorbital barely falling short of horizontal limb of preopercle in specimens of approximately 40 mm SL, in contact with that bone in larger specimens. Posterior margins of third through fifth infraorbitals falling slightly short of vertical limb of preo- percle. Premaxillary teeth in three series: primary row of 6 teeth gently curved in small- to medium-sized specimens, with ante- rior tooth somewhat displaced laterally and giving series slightly sigmoid appearance in larger specimens, but without pronounced gap between first and second tooth of series. Me- NUMBER 613 105 TABLE 19.—Morphometrics and meristics of Creagrutus flavescens, new species: (A) holotype of C. flavescens. MEPN 4622; (B) paratypes of C. flavescens (n=26); and (C) all specimens of C. flavescens from which counts and measurements were taken (n=82). Standard length is expressed in mm; measurements 1 to 14=percentages of standard length; 15 to 18=percentages of head length. Characters Standard length 1. Snout to anal-fin origin 2. Snout to pelvic-fin origin 3. Snout to pectoral-fin insertion 4. Snout to dorsal-fin insertion 5. Dorsal-fin origin to hypural joint 6. Dorsal-fin origin to anal-fin origin 7. Dorsal-fin origin to pelvic-fin insertion 8. Dorsal-fin origin to pectoral-fin insertion 9. Caudal peduncle depth 10. Pectoral-fin length 11. Pelvic-fin length 12. Dorsal-fin length 13. Anal-fin length 14. Head length 15. Postorbital head length 16. Snout length 17. Bony orbital diameter 18. Interorbital width Lateral line scales Scale rows between dorsal-fin origin and lateral line Scale rows between anal-fin origin and lateral line Predorsal median scales Branched dorsal-fin rays Branched anal-fin rays Branched pelvic-fin rays Pectoral-fin rays Vertebrae A 88.0 62.9 45.3 23.2 43.8 61.5 37.8 32.5 34.4 13.0 19.0 16.6 24.0 18.8 24.3 44.4 24.5 35.0 34.6 40 4 3 9 8 12 6 13 38 B Morphometrics 43.7-93.8 62.2-66.3 45.1^8.1 21.7-24.0 44.1^*8.4 56.7-61.9 35.0-37.9 30.0-32.6 32.8-35.6 11.9-13.7 18.4-22.3 16.5-18.6 24.0-26.5 17.1-21.0 23.1-25.2 38.3-45.5 24.4-30.1 34.5^0.6 28.1-35.0 Meristics 37-tO 4 3 9-10 8 10-12 6-7 12-13 36-39 C 30.7-93.8 60.5-67.6 45.1—48.1 21.7-26.3 43.8-48.4 55.5-61.9 34.4-40.4 30.2-35.1 32.0-36.6 11.5-13.7 18.0-23.3 15.3-19.5 22.8-26.5 17.1-22.2 23.1-26.7 38.3-45.5 24.4-30.1 33.3^0.6 28.0-35.0 37-40 4 3 9-10 8 9-12' 6-7 12-13 36-39 'Nine branched anal-fin rays present in only 1 of 108 examined type and nontype specimens. dial tooth of primary series separated from anteriortooth of contralateral series by distinct gap filled by fleshy fold, fold more elaborate in larger individuals; triangular cluster of 3 large teeth, with posterolateral tooth larger; and single tooth of form similar to that of primary series located lateral to fourth tooth of primary premaxillary tooth row. Maxilla with 2 or 3 tricuspidate teeth. Dentary with 5 teeth; first and second teeth distinctly larger than others, with second tooth slightly larger than first and approximately twice height of third; fourth and fifth teeth much smaller and compressed. Dorsal-fin rays ii,8 in all specimens. Dorsal-fin origin slightly anterior to vertical through pelvic-fin insertion. Profile of distal margin of dorsal fin distinctly concave. Anal-fin rays ii,9-12 (9 very rare). Profile of distal margin of anal fin dis- tinctly concave, with last unbranched and anterior two branched rays forming lobe. Mature males with hooks present on anterior 2 to 4 branched anal-fin rays. Pectoral-fin rays i, 11-12. Tip of pectoral fin extending posteriorly two-thirds to three-fourths of distance to pelvic-fin insertion. Pelvic-fin rays i,6,i or i,7; mature males with hooks on all branched pelvic-fin rays. Tip of pelvic fin extending posteriorly to anus. Gill rakers 7-9+10-13. COLORATION IN LIFE.—In life, species with overall yellow- ish cast to the head, body, and fins (R. Barriga, pers. comm., 1996). Recently collected specimens, in formalin for less than one week, with body and head silvery overall, with the silvery sheen much more pronounced on the portions of the body ven- tral of the midlateral body stripe, midlateral body stripe itself overlain by a dense silvery stripe. Portion of body dorsal of midlateral stripe with yellowish tint. Dorsal surface of head yellowish. Dorsal fin yellow with darker markings apparent in speci- mens in alcohol quite obvious, yellow pigmentation most in- tense on unbranched and anterior branched rays and continuing posteriorly as yellow band along central portions of rays and membranes of remaining branched rays. Caudal fin yellow, more so basally, with distal portions of rays less intensely pig- mented. Anal fin with patch of intense yellow pigmentation overlying central portions of unbranched rays and all but poste- 106 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY rior most branched rays, patch slightly posterodorsally angled and tapering in height posteriorly. Pelvic fin with intense yel- low pigmentation on central portions of all but lateralmost rays. Pectoral fin with yellow patch over central portion. COLORATION IN ALCOHOL.—Specimens retaining guanine on scales and relatively recently collected individuals silvery with ground coloration yellowish. Ground coloration of speci- mens in alcohol for longer than several months light tan. Dor- sal surface of head with field of relatively concentrated small, dark surface chromatophores underlain by larger chromato- phores located on surface of brain. Field of surface chromato- phores continuing anteriorly over snout, with pigmentation more concentrated dorsal and anterior to nostrils. Denser field of chromatophores proximate to nostrils continuous, with stripe of dark chromatophores extending posteriorly around ventral and posterior margins of orbit. Dorsal portions of opercle and infraorbitals posterior to orbit with field of scattered, dark chro- matophores. Scales of dorsal surface of body with chromatophores con- centrated along scale margin and over basal portion of exposed portion of scale; fields of dark chromatophore separated by hy- aline region. Intensity of dark pigmentation more pronounced along dorsal midline and gradually decreasing ventrally. Pre- dorsal region of many specimens, typically larger individuals or those with darker overall pigmentation, with distinct, narrow middorsal stripe in region situated dorsal of humeral mark. Hu- meral mark in specimens of 25 to 45 mm SL distinctly verti- cally elongate, extending from about one scale row above hori- zontal through pectoral-fin insertion to one scale row ventral of middorsal line. Anterior margin of mark nearly straight in smaller individuals, becoming more arched with increasing body size. Density of pigmentation within humeral mark not notably variable in smaller individuals. Ventral portion of mark becoming progressively less intensely pigmented in larger specimens. Larger individuals with anterior and, to lesser de- gree, posterior expansion of portion of mark centered along horizontal through middle of orbit. This expansion, in combi- nation with reduction in intensity of pigmentation in ventral portion of marks, results in dark humeral mark in form of in- verted comma in adults. Larger specimens with only scattered, dark chromatophores in region occupied by ventral portion of mark in smaller individuals. Midlateral portion of body with dark horizontal stripe formed by deep-lying and surface chro- matophores. Stripe diffuse anteriorly and not continuous with humeral mark; more dense in central portion and extending posteriorly onto caudal peduncle; becoming diffuse posteriorly on caudal peduncle. Dorsal fin with series of small, dark chromatophores along anterior margin of first and second unbranched rays. Mem- branes of branched rays with fields of small chromatophores extending over distal two-thirds of fin in smaller individuals, and nearly to fin-base in larger specimens, giving fin overall dusky appearance. Anal-fin membranes with small, dark chro- matophores along distal one-half to two-thirds of fin. Caudal fin with rays outlined and sometimes overlain by small dark chromatophores, giving it slightly dusky appearance. Pectoral and pelvic fins hyaline or with few small, dark, chromato- phores along fin-ray margins. ETYMOLOGY.—The specific name, flavescens, from the Latin flavus, for golden yellow, refers to the life coloration of the species. ECOLOGY.—Mature males, as shown by the presence of hooks on the rays of the anal and pelvic fins, are all less than 70 mm SL; all larger individuals evidently are females. One of the females, captured in early May, had large numbers of well-de- veloped eggs. Saul (1975:106) reported that this species (cited as C. beni) occurs "primarily in the swift waters of the Rio Aguarico. Specimens were taken along sandbars where a solid sand or mud bottom was present. Large rocks were lacking or widely scattered. One specimen was seined over bedrock at the mouth of a small stream during high water." Comparable conditions also are common to a number of other localities in which C. flavescens has been captured (R. Barriga, pers. comm., 1996). Examination of the stomach contents of two specimens of C. flavescens prepared for clearing and staining in this study re- vealed primarily parts of adult insects along with a small num- ber of chopped up seeds. Saul (1975:106), in his analysis of stomach contents for C. flavescens (his C. beni), found seeds, plant debris, insect debris, mayfly larvae (Ephemeroptera), stonefly nymphs (Plecoptera), caddisfly larvae (Trichoptera), beetle larvae (Coleoptera), fly larvae (Diptera, Chironomidae), ants (Hymenoptera, Formicidae), and a spider (Araneida). Ants and chironomid larvae were most abundant. In the Rio La Bermeja of the Rio San Miguel basin, north- eastern Ecuador, C. flavescens was captured together with C. amoenus (USNM 340973 and 340986, respectively). DISTRIBUTION.—Creagmtus flavescens occurs on the eastern slopes of the Andean piedmont in Ecuador (Figure 38, dots). GEOGRAPHIC VARIATION.—The holotype of Creagrutus fla- vescens and paratypes collected with it from the southern por- tions of the species range in Department of Pastaza, Ecuador, have 37 to 39 vertebrae. Of these, only one specimen has 39 vertebrae and a nearly equal number of individuals have 37 and 38 vertebrae, for an overall mean of 37.6 vertebrae. Nontype specimens from lower elevation Peruvian localities in the Rio Tigre system, which originates in the Department of Pastaza, Ecuador, have 38 or 39 vertebrae with a mean of 38.2. Speci- mens of C. flavescens from the central and northern portions of the known range of the species (Departments of Napo and Su- cumbios) have a range of 36 to 38 vertebrae with a strong modal value of 37 vertebrae and a mean of 36.99 vertebrae. Paralleling this variation in the range of modal values of the vertebrae are differences in the range and modal values for lat- eral line scales. The population sample from the type locality (Department of Pastaza) has 38 to 40 scales and a mean value of 39.0 scales, whereas the more numerous samples from the central and northern portions of Ecuador have a range of 37 to 40 scales with a mean of 38.4 scales. These minor differences do not permit the recognition of more than one species within what is herein identified as C. flavescens and may simply re- NUMBER 613 107 FIGURE 41.—Creagrutus flavescens, new species, holotype, MEPN 4622, 88.0 mm SL; Ecuador, Pastaza, Rio Tiguino basin, Rio Tiguino No. 3 (unnamed tributary of RioTiguino; l°07'35"S, 76°56'52"W). fleet the limited sample sizes from the southern portions of the species range. Two lots of C. flavescens from the Rio Tigre system in the Department of Loreto, Peru, agree with Ecuadorian popula- tions of the species in the vast majority of features but are rela- tively deeper bodied than is typical for Ecuadorian samples of the species. The three larger specimens in these lots (NRM 26380, 2 of 8 specimens; NRM 26372, 1 specimen) conse- quently are at the upper limit for the proportional values that reflect body depth. In these Rio Tigre specimens the distance from the dorsal-f in origin to the anal-fin origin is 37.0%-40.3% of SL versus a range of 32.4%-37.9% of SL in Ecuadorian samples. Similarly, the distance from the dorsal-fin origin to the pelvic-fin insertion is 32.0%-35.1% versus 28.2%-32.8% of SL, and the distance from the dorsal-fin ori- gin to the pectoral-fin insertion is 34.5%-36.6% versus 32.0%-35.6% of SL for the Peruvian versus Ecuadorian sam- ples, respectively. Further samples from Peru and intervening regions are necessary to determine whether the differences should be recognized taxonomically or only represent geo- graphic or ecophenotipic variation. REMARKS.—Fowler (1943a:239) described Creagrutus amoenus on the basis of a holotype and three paratypes. One of the paratypes of C. amoenus (ANSP 70500, 62.8 mm SL) is ac- tually a specimen of C. flavescens. Boulenger (1887:281) reported Creagrutus muelleri from Canelos, a town on the Rio Bobonaza of eastern Ecuador. Al- though that locality lies within the general distributional range of C. muelleri, the specimen that apparently served as the ba- sis of that report (BMNH 1880.12.8:116) lacks the arrange- ment of premaxillary dentition typical of that species. The specimen is in somewhat poor condition and lacks pigmenta- tion, thereby precluding a definitive identification, but it is tentatively considered to be an individual of C. flavescens based on where it was collected and the available meristic and morphometric evidence. Saul (1975:106) reported C. beni from the Rio Aguarico of eastern Ecuador, using the broad concept of that species com- mon at that time. Analysis has shown that his specimens are C. flavescens. MATERIAL EXAMINED.—689 (82, 30.7-93.8). HOLOTYPE.—ECUADOR. Pastaza: Rio Tiguino basin, Rio Tiguino No. 3 (unnamed tributary of Rio Tiguino; l°07'35"S, 76°56'52"W), collected by R. Barriga, 21 Apr 1989, MEPN 4622, 1 (88.0). PARATYPES.—26 specimens (26,43.7-93.8). ECUADOR. Pastaza: Rio Tiguino basin, Rio Tiguino No. 3 (unnamed tributary of Rio Tiguino; l°07'35"S, 76°56'52"W), collected with holotype, MEPN 4642, 7 (43.7-82.3); USNM 340974, 8 (61.7-90.7). Napo: Estero Yampuna, 300 m from Campamento Petrolano Yampuna, collected 18 Dec 1988, by R. Barriga et al., MEPN 6380, 7 (53.9-93.8); USNM 340975,4 (55.5-88.6). NONTYPE SPECIMENS.—652 specimens (55, 30.7-88.7). COLOMBIA. Caqueta: Florencia, Rio Orteguasa (=Orteg- uaza; approximately \°A5^ 75°35'W), ANSP 70500, 1 (62.8, paratype of Creagrutus amoenus). Rio Caqueta basin, Morelia (1°29'N, 75°44'W), ANSP 166592, 3. Rio Orteguaza basin, small oxbow stream across Rio Orteguaza from Tres Esquinas (0°43'N, 75°61'W), CAS 150658, 3. Putomayo: Rumiyaco (1000 m elevation), NRM 26424, 3. PERU. Loreto: Rio Tigre drainage, San Jacinto, quebrada at km 53 (2°32'S, 75°44'W), NRM 26372, 1 (78.1). Rio Corn- entes drainage, Teniente Lopez, quebrada tributary' to Rio Cor- rientes, at military camp (approximately 3°43'S, 74°45'W), NRM 26380, 8 (2, 50.2-71.9). ECUADOR. Napo: Rio Punino, tributary of Rio Payamino, above Coca (^Puerto Francisco de Orellana; approximately 0°27'S, 77°08'W), MCZ 51493, 32 (15, 54.5-65.6). Rio Blanco, first tributary N of Rio Tiputini, above bridge on road 108 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY to Coca (^Puerto Francisco de Orellana) (0°44'30"S, 76°53'W), MEPN 5248, 10. Quebrada Capihuara, northern tributary of Rio Payamino, 6.5 river km below mouth of Rio Tutapischo (approximately 0°30'S, 77°14'30"W), MEPN 5249, 20; FMNH 106029, 32. Quebrada Tiuyacu, first upstream trib- utary of Rio Churuyacu, near mouth of latter in Rio Payamino (approximately 0°29'30"S, 77°18'W), MEPN 5253, 9. Rio Ti- putini basin, Estero Culiyacu (0°43'08"S, 76°50'12"W), MEPN 6611, 4; MEPN 6374, 1. In cave near Archidona (approxi- mately 0°55'S, 77°48'W), ZMA 119.151, 1. Small stream trib- utary to Rio Payamino, approximately 1.6 km from mouth of river, MCZ 51495, 2. Rio Copataza (=Copotaza), BMNH 1981.1.5:341-354, 14. Estero Culiyacu, left margin of Rio Ti- putini (mouth of river at 0°48'S, 76°33'W), USNM 311356, 13. Rio Napo at Puerto Misahuali (l°2'30"S, 77°39'12"W), FMNH 106033, 18. Pastaza: Canelos (Rio Bobonaza system, 1°35'S, 77°45'W), BMNH 1880.12.8:116, 1 (65.3). Rio Bobonaza, near settlement of Montalvo (2°04'S, 76°58'W), MEPN 4639, 8. Rio Tiguino basin, Rio Tiguino No. 3 (unnamed tributary of Rio Tiguino; l°07'35"S, 76°56'52"W), MEPN 9621, 43. Rio Tigrillo, tributary of Rio Conambo, Pozo Tigrillo, Tenneco camp (exact locality uncertain), MEPN 6609, 18. Rio Pastaza, near Puyo (approximately 1000 m elevation; 01°30'S, 78°00'W), UMMZ 203872, 1. Sucumbios: Rio Aguarico basin, mouth of Rio Shushifindi, ANSP 137613, 12 (10, 58.0-88.7). Rio San Miguel basin, Rio La Bermeja, in front of Commmu- nidad Shuor Chari (approximately 0°10TM, 76°25'W), MEPN uncataloged, 15 (30.7-81.1); USNM 340973, 10 (38.5-75.8; 2 specimens cleared and counterstained for cartilage and bone). Rio Aguarico, several km by river above mouth of Rio Eno (approximately 0°ll 'S, 76°30'W), MEPN 5258, 8. Rio Aguar- ico, Guarumo (0°01'S, 76°37'30"W), MEPN 5273, 150; MEPN 9836, 10. Northern tributary of Rio Aguarico, 2-3 river km upstream of mouth of Rio Pushino (0°03'N, 76°56'W), MEPN 5261, 100. Rio Aguarico, beach above mouth of Rio Due (0°04'30"N, 77°22'24"W), MEPN 5250, 10. Rio Duguno, approximately 1 km S of Communa Cafan del Duguno (0°02'10"S, 77°05'18"W), MEPN uncataloged, 1. Rio Aguar- ico, at Santa Cecilia (00°06'N, 76°51'W), ANSP 130466, 7 (formerly KU 13444); ANSP 130470, 8; KU 13447, 18; ANSP 130468, 10. Rio Aguarico, just upstream from Lago Agrio at Cancha (0°3'30"N, 76°53'W), FMNH 106035,47. Creagrutus gephyrus Bohlke and Saul, 1975 FIGURES 42,43, TABLE 20 Creagrutus gephyrus Bohlke and Saul, 1975:25, figs. 1-4 [type locality: Ecua- dor, Napo (now in Sucumbios), Rio Aguarico, at Santa Cecilia].—Saul, 1975:106 [Ecuador, Napo (now in Sucumbios), Rio Aguarico, at Santa Cecil- ia; ecology and habitat].—Bohlke, 1984:47 [depository of holotype and por- tion of paratype series].—Stewart et al., 1987:26 [Ecuador, Rio Napo ba- sin].—Barriga, 1991:17 [tropical eastern Ecuador; common name].— 1994:29 [Ecuador, Parque Nacional Yasuni]. DIAGNOSIS.—The combination of the three standard compo- nents of premaxillary dentition typical for most Creagrutus species (see "Premaxillary Dentition in Creagrutus and Pia- TABLE 20.—Morphometrics and menstics of Creagrutus gephyrus: (A) holo- type of C. gephyrus, ANSP 130516; and (B) all other specimens of C. gephyrus from which counts and measurements were taken (n=25). Standard length is expressed in mm; measurements 1 to 14=percentages of standard length; 15 to 18=percentages of head length. Dash indicates measurement that could not be taken as a consequence of damage to specimen. Characters Standard length 1. Snout to anal-fin origin 2. Snout to pelvic-fin insertion 3. Snout to pectoral-fin insertion 4. Snout to dorsal-fin origin 5. Dorsal-fin origin to hypural joint 6. Dorsal-fin origin to anal-fin origin 7. Dorsal-fin origin to pelvic-fin insertion 8. Dorsal-fin origin to pectoral-fin insertion 9. Caudal peduncle depth 10. Pectoral-fin length 11. Pelvic-fin length 12. Dorsal-fin length 13. Anal-fin length 14. Head length 15. Postorbital head length 16. Snout length 17. Bony orbital diameter 18. Interorbital width Lateral line scales Scale rows between dorsal-fin origin and lateral line Scale rows between anal-fin origin and lateral line Predorsal median scales Branched dorsal-fin rays Branched anal-fin rays Branched pelvic-fin rays Pectoral-fin rays Vertebrae A B Morphometrics 64.9 66.9 49.9 24.2 49.5 53.0 30.8 25.9 32.0 11.1 17.7 14.9 - 16.2 28.0 41.0 29.0 27.7 25.6 29.5-64.6 61.4-67.7 46.9-50.6 23.1-26.7 46.2^9.6 52.2-57.0 27.8-31.0 22.7-26.2 27.8-32.5 10.5-11.6 16.1-18.6 13.7-15.5 19.6-22.0 15.5-17.7 26.0-28.2 41.0-46.0 24.0-29.4 28.4-36.0 25.4-28.9 Meristics 39 4 3 10 8 11 6 13 37 37-39 3-t 3 9-10 8 10-11 6 13-14 37 bina"), and the possession of 7 to 10 maxillary teeth and 10 or 11 dentary teeth in adult specimens discriminates Creagrutus gephyrus from all congeners and Piabina argentea, all of which either have two irregular rows of premaxillary dentition (C. maxillaris and C. cracentis) or 2 to 5 maxillary teeth and 5 to 7 dentary teeth {Piabina argentea and all remaining Crea- grutus species). Creagrutus gephyrus also is characterized by a autapomorphic modification of the sphenotic spine (see "Sphe- notic," under "Character Description and Analysis"). DESCRIPTION.—Morphometric and meristic data for Crea- grutus gephyrus in Table 20. Overall appearance of head and body elongate compared with many congeners. Maximum body depth at vertical through dorsal-fin origin in specimens without distended abdomens, somewhat anterior of that point in ripe females and specimens with full stomachs. Dorsal pro- file of head smoothly convex between margin of upper lip and vertical through posterior margin of posterior nares. Snout tip somewhat more blunt in larger specimens. Dorsal profile of head posterior to vertical through posterior nares posterodor- sally inclined and straight to slightly convex. Dorsal profile of NUMBER 613 109 FIGURE 42.—Creagrutus gephyrus, USNM 324461, 40.7 mm SL; Ecuador, Napo, Rio Napo, at Coca (=Puerto Francisco de Orellana; latter locality at 0°28'S, 80°22'W). posterior portion of head continued without interruption onto slightly convex predorsal region of body. Dorsal profile of body between dorsal-fin origin and caudal peduncle straight or more typically somewhat convex in region of adipose fin. Ven- tral profile of head smoothly rounded, without obtuse angle at anteroventral region of dentary. Profile of abdominal region typically straight in smaller individuals, varyingly convex in larger specimens. When abdominal profile straight, abdomen somewhat transversely flattened. Upper jaw longer than, and overhanging, lower jaw, but with difference in length of jaws less pronounced than in most Crea- grutus and Piabina species. Anterior surface of snout fleshy, albeit less so than in many congeners. Papillae limited to ante- rior portion of snout, upper lip, and outer fleshy flaps and pli- cae extending between outer and medial premaxillary teeth. Lower lip somewhat fleshy anteriorly, although less so than in most Creagrutus species, with few scattered papillae. Infraorbital series well developed, covering approximately two-thirds of check in specimens of approximately 17 mm SL; extending over nearly all of that region of head in larger indi- viduals. Ventral margin of third infraorbital contacting horizon- tal limb of preopercle. Posterior margins of third through fifth infraorbitals falling slightly short of vertical limb of preopercle. Premaxillary dentition in three series: nearly straight primary row typically with 5, rarely 6, tricuspidate teeth (see under "Geographic Variation," below, concerning this intraspecific difference), with medial teeth of contralateral series distinctly separated; triangular cluster of three larger teeth with postero- lateral tooth slightly larger; and single tricuspidate tooth with posteriorly recurved central cusp, tooth located lateral to region between third and fourth teeth of primary premaxillary row. Maxilla with 7 to 11 tricuspidate teeth; 3 anterior maxillary teeth largest with teeth posterior to these becoming progres- sively smaller. Middle teeth of maxillary series with middle cusp posteriorly recurved. Dentary with 10 or 11 teeth. Ante- rior 3 teeth distinctly larger and angled anterodorsally or ante- rolaterally depending on position in jaw. Fourth to last teeth in series gradually decreasing in size. Two anteriormost dentary teeth with 4 cusps, fourth cusp very small, on posterior margin of tooth. All other dentary teeth tricuspidate other than for pos- teriormost 1 or 2 conical teeth (number of conical teeth de- pending on whether 10 or 11 dentary teeth present). Central cusps of first and second teeth nearly straight, those of remain- ing teeth posteriorly recurved to varying degrees. Dorsal-fin rays ii,8. Dorsal-fin origin at, or slightly anterior to, vertical through pelvic-fin insertion. Profile of distal margin of dorsal fin slightly concave. Anal-fin rays ii, 10—11. Profile of distal margin of anal fin distinctly convex, with posterior un- branched and 3 anterior branched rays forming distinct lobe. Single, bilaterally paired hooks present on anterior 2 branched anal-fin rays in mature males (observed in only 2 of 20 speci- mens). Hooks restricted to posterolateral surface of main shaft. Pectoral-fin rays i, 12-13. Tip of pectoral fin extending posteri- orly approximately two-thirds of distance to pelvic-fin insertion. Pelvic-fin rays i,6,i. Tip of pelvic fin falling somewhat short of anus. Mature males with pelvic-fin hooks, when present, on basal unsegmented portions and most segments other than dis- talmost ones on all branched rays. Mature males with hooks also present on segmented portion of medial unbranched pelvic-fin rays, again with exception of distal portion of ray. Gill rakers 6-7 + 9-11; those of first arch, especially first cer- atobranchial, relatively long. COLORATION IN ALCOHOL.—Dorsal surface of head with smaller dark chromatophores on surface and larger, deep-lying dark chromatophores, particularly over membranes on brain. Field of surface chromatophores extending anteriorly over snout and upper lip. Chromatophore field anterior to nares con- tinuous posteroventrally with band of dark chromatophores continuing posteroventrally to ventral margin of eye and then around posterior margin of orbit. Dorsal portions of opercle and infraorbital series with pattern of scattered, dark chromato- phores. Margin of upper lip dark medially. Scales of dorsal por- tion of body underlain by series of chromatophores in regions where scales overlap; dark pigmentation forming somewhat re- 110 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY FIGURE 43.—Map of central and northern South America showing geographic distribution of Creagrutus gephyrus (dots, 1 =type locality, 2 and 3=areas where both C. gephyrus and C. gracilis occur, 4=area where both C. gephyrus and C. holmi occur), Creagrutus gracilis (squares, 5=type locality; C. holmi also collected in this area, see also under C. gephyrus), Creagrutus gyrospilus (solid stars, 6=type locality), Creagrutus holmi (trian- gles, 7=type locality, see also under C. gephyrus and C. gracilis), Creagrutus hysginus (diamonds, 8=type local- ity), and Creagrutus ignotus (open stars, 9=type locality) (some symbols represent more than one locality or lot of specimens). ticulate pattern. Reticulate pattern merges into continuous field of chromatophores along dorsal midline. Humeral mark appearing as vertically elongate pigment patch extending from slightly above horizontal of pectoral-fin insertion, across lateral line, to approximately one scale ventral of middorsal line. Anterior and posterior margins of humeral mark somewhat irregular, but mark typically tapers somewhat ventrally. Body with dark midlateral band formed by surface and deep-lying chromatophores. Deep-lying stripe of dusky pigmentation extending from under dorsal fin posteriorly to rear of caudal peduncle in medium-sized individuals and far- ther anteriorly, nearly to humeral mark, in larger specimens. Deep-lying stripe overlain by diffuse, wider band of small dark surface chromatophores extending posteriorly from humeral mark to rear of caudal peduncle. Dorsal fin with margin of longest unbranched ray and distal one-half of anterior branched rays and associated membranes with dark chromatophores; scattered, dark chromatophores on posterior portion of fin. Most branched anal-fin rays with all but distal portions delimited by dark chromatophores. Caudal- and pectoral-fin rays outlined by dark chromatophores. Pelvic fin with scattered chromatophores. ECOLOGY.—Saul (1975:106) reported that Creagrutus ge- phyrus was captured most often in the main portion of the Rio Aguarico of eastern Ecuador over a packed sand and mud bot- tom, but some individuals occurred in a sluggish backwater of NUMBER613 111 the river. The specimens examined by Saul had fed on fish and insect larvae. The single specimen prepared for clearing and staining in this study and examined for stomach contents had fed exclusively on insect larvae. COMMON NAME.—Ecuador: "Sardina" (Barriga, 1991:17). DISTRIBUTION.—Creagrutus gephyrus occurs across the An- dean piedmont rivers of eastern Ecuador and northeastern Peru (see "Geographic Variation," below, concerning latter popula- tion sample; Figure 43). GEOGRAPHIC VARIATION.—The southern-most record for Creagrutus gephyrus is based on three lots of specimens from Amazonas province of northeastern Peru (LACM 36357-56, 39908-3, 42114-10). These specimens agree with the Ecuador- ian samples of the species in all features other than for having 6 rather than 5 teeth in the primary premaxillary row. Given the limited size of the C. gephyrus sample from northeastern Peru and the intraspecific variation in the number of teeth in the pri- mary premaxillary tooth row in some other Creagrutus species, we prefer to not recognize the specimens from that region as a separate species at this time. If further samples prove that this is an invariant difference between the populations, it may war- rant taxonomic recognition. MATERIAL EXAMINED.—93 specimens (33, 29.5-64.9). ECUADOR. Sucumbios: Tributary of Rio Aguarico, at Santa Cecilia (0°06'N, 76°51'W), ANSP 130516, 1 (64.9, holotype of Creagrutus gephyrus); ANSP 130517, 1 (60.3, paratype of Creagrutus gephyrus); ANSP 130519, 1 (paratype of Creagru- tus gephyrus); ANSP 130520, 1 (paratype of Creagrutus ge- phyrus); ANSP 130521, 1 (35.8, paratype of Creagrutus ge- phyrus); ANSP 130522, 1 (35.7, paratype of Creagrutus gephyrus); KU 13468, 2 (37.4-40.9, paratypes of Creagrutus gephyrus). Rio Aguarico at Destacamento Militar Santa Ce- cilia, FMNH 103011, 6. Rio Aguarico, approximately 1 river km upriver of confluence with Rio Shushufindi (0°17'N, 76°25'W), MEPN 4629, 5. Rio Aguarico near Destacamento Militar Cuyabeno and confluence of Rio Cuyabeno and Rio Aguarico (0°15'30"S, 75°53'30"W), FMNH 103008, 1; MEPN uncataloged, 13 (10, 42.0-47.3). Rio Aguarico, slightly below mouth of Rio Pushino (0°2'36"N, 76°54'24"W), MEPN uncat- aloged, 5. Rio Aguarico, S of Shushufindi, USNM 352933, 3. Rio San Miguel at Tapischa (0°12'30"N, 76°13'W), FMNH 103006, 5. Rio Aguarico, 1 km above mouth of Rio Lagartoco- cha, beaches on both shores (0°38'S, 75°18'W), MEPN uncata- loged, 3. Napo: Rio Napo, at Coca (=Puerto Francisco de Orel- lana; 0°28'S, 80°22'W), USNM 324461, 4 (3, 29.5-40.7; 1 specimen cleared and counterstained for cartilage and bone). Rio Napo, near Coca (= Puerto Francisco de Orellana; latter lo- cality at 0°28'S, 80°22'W), USNM 343879, 2 (45.3^9.7). Rio Napo, tributary stream approximately 25 km downstream of Coca (= Puerto Francisco de Orellana; latter locality at 0°28'S, 80°22'W), USNM 340953, 6 (4, 41.8^9.6; 1 specimen cleared and counterstained for cartilage and bone). Rio Napo at Puerto Misahualh (l°2'30"S, 77°39'12"W), FMNH 103002, 10. Rio Jatunyacu at Puerto Napo (l°03'S, 77°47'W), FMNH 103004, 1. Quebrada Capihuara, tributary to Rio Payamino (0°30'S, 77°14'30"W), FMNH 103009, 7. Pastaza: Rio Tiguino basin, Rio Tiguino No. 3 (unnamed tributary of Rio Tiguino; 1°O7'35"S, 76°56'52"W, collected with holotype), MEPN un- cataloged, 3. Rio Tiguino basin, Tiguino No. 1 (unnamed tribu- tary of Rio Tiguino), MEPN 9580, 3. The following specimens are tentatively identified as Crea- grutus gephyrus (see discussion under "Geographic Variation," above, with respect to their identification). PERU. Amazonas: Rio Cenepa, vicinity of Huampani (4°28'S, 78°10'W), LACM 36357-56, 1 (64.6). Rio Caterpiza (3°55'S, 77°42'W), LACM 39908-3, 6 (1 , 31.6); LACM 42114-10, 1 (48.6). Creagrutus gracilis, new species FIGURES 43, 44, TABLE 21 DIAGNOSIS.—The combination of the possession of premax- illary dentition arranged in the three components generalized for most of the species of Creagrutus and Piabina without a distinctly larger gap between the first and second teeth of the primary series, 3 or 4 teeth on the maxilla, 5 teeth in the pri- mary tooth row of the premaxilla, 5 or 6 dentary teeth, 39 to 43 lateral line scales without a lamellar process over each pore, 9 or 10 predorsal median scales, 4 scale rows between the dorsal- fin origin and the lateral line, 3 scale rows between the anal-fin origin and the lateral line, 38 to 40 vertebrae, 10 or 11 branched anal-fin rays, 2 post-anal median scales to the anal-fin origin, 8 to 10 gill rakers on the lower limb of the first gill arch, 11 to 14 gill rakers on the upper limb of the first gill arch, the snout length (24.7%-28.6% of HL), the well-developed third infraor- bital contacting the horizontal limb of the preopercle in larger individuals, the lack of a series of dark midlateral spots on the body, the discrete, vertically elongate, somewhat posterodor- sally angled, ovoid, humeral mark without straight anterior and posterior margins, but not in the shape of an inverted comma, the lack of a spot of distinct pigmentation on the basal portions of the middle caudal-fin rays, and the absence of a discrete patch of dark pigmentation on the middle portion of the ante- rior dorsal-fin rays distinguishes Creagrutus gracilis within the clade composed of Creagrutus and Piabina. DESCRIPTION.—Morphometric and meristic data for Crea- grutus gracilis in Table 21. Head and body relatively slender at all sizes. Greatest body depth slightly anterior to vertical through pelvic-fin insertion. Dorsal profile of head distinctly convex from margin of lower lip to vertical through anterior nostril, slightly convex, or more usually straight, from that point to rear of supraoccipital spine. Interorbital region ob- tusely flattened transversely. Dorsal profile of body very slightly convex from rear of head to dorsal-fin origin, convex- ity slightly more pronounced in larger specimens. Predorsal surface of body with slight middorsal ridge, ridge more devel- oped proximate to dorsal-fin origin. Ventral profile of head with distinct obtuse angle at anteroventral corner of dentary, profile nearly straight from that angle to isthmus. Prepelvic re- 112 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY TABLE 21.—Morphometrics and meristics of Creagrutus gracilis, new species: (A) holotype of C gracilis, LACM 41724-27; and (B) paratypes of C. gracilis (n=40). Standard length is expressed in mm; measurements 1 to 14=percent- ages of standard length; 15 to 18=percentages of head length. Characters Standard length 1. Snout to anal-fin origin 2. Snout to pelvic-fin insertion 3. Snout to pectoral-fin insertion 4. Snout to dorsal-fin origin 5. Dorsal-fin origin to hypural joint 6. Dorsal-fin origin to anal-fin origin 7. Dorsal-fin origin to pelvic-fin insertion 8. Dorsal-fin origin to pectoral-fin insertion 9. Caudal peduncle depth 10. Pectoral-fin length 11. Pelvic-fin length 12. Dorsal-fin length 13. Anal-fin length 14. Head length 15. Postorbital head length 16. Snout length 17. Bony orbital diameter 18. Interorbital width Lateral line scales Scale rows between dorsal-fin origin and lateral line Scale rows between anal-fin origin and lateral line Predorsal median scales Branched dorsal-fin rays Branched anal-fin rays Branched pelvic-fin rays Pectoral-fin rays Vertebrae A B Morphometrics 55.8 63.3 47.1 24.4 46.2 60.0 31.9 26.2 30.1 10.9 19.7 15.7 23.2 17.0 25.8 45.5 27.8 32.3 27.6 22.3-58.6 61.0-66.4 45.4-49.6 22.5-25.0 43.9^16.6 53.7-60.2 30.2-33.8 25.2-28.5 29.8-32.6 10.6-12.4 17.6-20.6 13.7-16.6 19.5-24.9 15.9-18.9 23.3-26.6 38.0-45.8 24.7-28.6 32.0-36.7 27.6-32.0 Meristics 42 4 3 9 8 11 6 13 39 39-43 4 3 9-10 8 10-11 6-7 12-14 38-40 gion of body nearly straight in smaller specimens and slightly convex in larger individuals within Peruvian samples; dis- tinctly convex in sample from Rio Napo basin, eastern Ecuador (ANSP 134499) in which specimens are all larger than exam- ined Peruvian samples. Head moderately obtusely pointed in lateral view, less so than in many congeners; obtusely pointed in dorsal view. Up- per jaw longer than, and overhanging, lower jaw. Snout fleshy, more so anteriorly, papillae scattered over anterior portion of snout and lateral surface of maxilla, more concentrated along anterior and ventral margin of upper lips and fleshy folds and plicae extending between outer and medial premaxillary teeth, particularly medially. Lower lip very fleshy with numerous pa- pillae on dorsal and anterior margins; scattered papillae on ven- tromedial region of lip. Infraorbital series moderately developed. Third infraorbital moderately large and horizontally elongate, with its ventrally convex lower margin falling short of contact with horizontal limb of preopercle in specimens up to approximately 50 mm SL. Central portion of ventral margin of third infraorbital ap- proaching or barely contacting the horizontal limb of preoper- cle in individuals larger than approximately 50 mm SL. Poste- rior margins of third through fifth infraorbitals separated by narrow gap from vertical limb of preopercle. Premaxillary dentition in three series: primary row slightly sigmoid, with 5 teeth in all specimens, without pronounced gap between first and second tooth of series but with medial tooth separated from contralateral equivalent by gap filled by fleshy fold; triangular cluster of 3 larger teeth lying medial to primary row, with posterolateral tooth somewhat larger than others; and single tooth of form similar to that of primary series occurring lateral to third tooth of primary premaxillary series, or lateral to area of contact of third and fourth teeth. Maxillary with 3 or 4, usually 4, tricuspidate teeth. Dentary with 5 or 6 tricuspidate teeth; first and second teeth distinctly larger than others, sub- equal or second slightly larger; both approximately twice height of third tooth; fourth and fifth or sixth teeth (when 6 teeth present) distinctly smaller and compressed. Dorsal-fin rays ii,8 in all specimens. Dorsal-fin origin slightly anterior to vertical through pelvic-fin insertion. Profile of distal margin of dorsal fin concave. Anal-fin rays ii, 10—11 or iii,10 (only one specimen). Profile of distal margin of anal fin concave, with last unbranched and anterior 2 or 3 branched rays forming distinct lobe. Hooks on anal-fin rays present in mature males of many Creagrutus species not found in exam- ined specimens. Pectoral-fin rays i, 11-13. Tip of pectoral fin extending one-half to two-thirds of distance to pelvic-fin inser- tion. Pelvic-fin rays i,6,i or i,7 (typically i,7 in larger individu- als). Pelvic-fin length somewhat variable, tip of fin extending posteriorly nearly to anal-fin origin in some individuals, or fall- ing up to 2 scales short of that point in some specimens. Hooks of pelvic-fin rays present in mature males of many Creagrutus species not found in examined specimens. Gill rakers 8-10+ 11-14 (14 in only 1 specimen). COLORATION IN ALCOHOL.—Nontype specimens retaining guanine on scales silvery golden; guanine layer variably mask- ing dark pigmentation of humeral mark and midlateral stripe of body. Specimens lacking guanine on scales with ground colora- tion light tan. Dorsal surface of head with field of small, dark surface chromatophores and series of deep-lying, larger, dark chromatophores on membranes overlying brain. Field of small surface chromatophores extending anteriorly over snout and upper lip. Region anterior to nares without dense concentration of dark chromatophores found in many Creagrutus species. Anterior portion of lower lip with scattered, small, dark chro- matophores. Region anteroventral of orbit with region of con- centrated chromatophores comparable to that in many conge- ners, but this patch not continued along ventral and posterior margins of orbit as in many other Creagrutus species. Dorsal infraorbitals and central and dorsal portions of opercle covered with scattered chromatophores. Scales of dorsal portion of body with fields of chromato- phores along posterior margin; width of field greater dorsally, nearly forming continuous area of chromatophores along mid- dorsal portions of body, more so anterodorsally. Midlateral por- tion of body with indistinct stripe extending from slightly pos- NUMBER 613 113 FIGURE 44.—Creagrutus gracilis, new species, holotype, LACM 41724-27, 55.8 mm SL; Peru, Amazonas, Pro- vincia Condorcanqui, Rio Santiago, at La Poza (4°01'S. 77°47'W). terior of humeral mark to rear of caudal peduncle. Stripe formed by field of scattered, small, dark, surface chromato- phores and larger, deep-lying, dark chromatophores; latter more concentrated along dorsal margin of stripe. Humeral mark prominent, main portion roughly ovoid, vertically elon- gate, with slightly anteriorly directly dorsal and ventral exten- sions. Anterior margin of dorsal fin with series of small, dark chro- matophores; distal portions of membranes with scattered, dark chromatophores; intensity of pigmentation more pronounced anteriorly and increasing overall ontogenetically. Anal-fin rays outlined with series of small dark chromatophores, more so on distal one-half of central rays. Caudal fin with membranes and margins of rays delimited by small, dark chromatophores. In- tensity of caudal-fin pigmentation greater in larger individuals, giving fin dusky overall appearance in those specimens. Pecto- ral and pelvic fins mostly hyaline, with scattered, dark chro- matophores. ETYMOLOGY.—The specific name, gracilis, from the Latin for slender or gracile, refers to the relatively shallow body of this species compared to many congeners. ECOLOGY.—Nothing is known about the ecology of Crea- grutus gracilis, but all examined specimens originated in re- gions of less than 500 m elevation. DISTRIBUTION.—Creagrutus gracilis is known from Amazo- nas and Loreto states of Peru and various localities along the eastern slope of the Andean Cordilleras in Ecuador (Figure 43, squares). MATERIAL EXAMINED.—191 specimens (43,22.3-77.0). HOLOTYPE.—PERU. Amazonas: Provincia Condorcanqui, Rio Santiago, at La Poza (4°01'S, 77°47'W), collected by D.J. Stewart, 20 Mar 1982, LACM 41724-27, 1 (55.8). P A R A T Y P E S . ^ 0 specimens (40, 22.3-58.6). PERU. Amazonas: Provincia Condorcanqui, Rio Santiago, at La Poza (4°01'S, 77°47'W), collected with holotype, LACM 41724-32, 10 (27.2-49.5); USNM 341370, 10 (23.3-42.1; 2 specimens cleared and counterstained for cartilage and bone); MUSM 8864, 10 (22.3-36.6). Loreto: Provincia de Alto Ama- zonas, Rio Huallaga, mouth of Rio Paranapura, at Yurimaguas (5°54'S, 70°05'W), collected by I. Samanez, 26 Apr 1995, MUSM 10760, 6 (39.2-58.6); USNM 344534, 4 (52.3-54.4). NONTYPE SPECIMENS.—150 specimens (12, 42.0-77.0). ECUADOR. Sucumbios: Rio Aguarico, 1 km above mouth of Rio Lagartococha, beaches on both shores (0°38'S, 75°18'W), MEPN 4620, 2 (42.0-43.8). Rio Aguarico, few km upstream from mouth of Rio Eno (0°l l'S, 76°30'W), FMNH 106031, 24. Rio Napo basin, near mouth of Rio Panayacyu, at elevation of 230-250 m (approximately 00°25'S, 76°07'W), ANSP 31311, 1 (53.4). Napo: Rio Napo, sand bank opposite Coca (^Puerto Francisco de Orellana; 0°28'S, 76°58'W), ANSP 134499, 9 (59.0-77.0). PERU. Nevate (locality not located in gazetteers), LACM 47268-1, 1. Amazonas: Provincia Condorcanqui, Rio Santiago, at La Poza (4°01'S, 77°47'W; collected with holotype), LACM 41724-33, 113. Creagrutus gyrospilus, new species FIGURES 43,45, TABLE 22 DIAGNOSIS.—The combination of the possession of premax- illary dentition arranged in the three components generalized for most of the species of Creagrutus and Piabina without a distinctly larger gap between the first and second teeth of the primary series, 6 teeth in the primary series of each premaxilla, 3 or 4, rarely 2, maxillary teeth, 5 or 6 teeth on each dentary, 10 to 12 median predorsal scales, 36 to 39 lateral line scales with- out a lamellar process over each pore, usually 4 scale rows be- tween the dorsal-fin origin and the lateral line, 2 post-anal scales to the anal-fin origin, 3 scale rows between the anal-fin origin and lateral line, usually 10 or 11 branched anal-fin rays, 5 to 8 gill rakers on the upper limb and 9 to 11 gill rakers on the lower limb of the first gill arch, 35 to 37 vertebrae, the caudal peduncle depth (11.3%-13.2% of SL), the postorbital length (45.0%-50.6% of HL), the bony diameter (25.8%-32.7% of 114 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY TABLE 22.—Morphometrics and meristics of Creagrutus gyrospilus. new species: (A) holotype of C. gyrospilus, INHS 69479; (B) paratypes of C. gyrospilus (n=40); and (C) nontypes of C. gyrospilus (n=3). Standard length is expressed in mm; measurements 1 to 14=percentages of standard length; 15 to 18=percentages of head length. Characters Standard length 1. Snout to anal-fin origin 2. Snout to pelvic-fin insertion 3. Snout to pectoral-fin insertion 4. Snout to dorsal-fin origin 5. Dorsal-fm origin to hypural joint 6. Dorsal-fin origin to anal-fin origin 7. Dorsal-fin origin to pelvic-fin insertion 8. Dorsal-fin origin to pectoral-fin insertion 9. Caudal peduncle depth 10. Pectoral-fin length 11. Pelvic-fin length 12. Dorsal-fin length 13. Anal-fin length 14. Head length 15. Postorbital head length 16. Snout length 17. Bony orbital diameter 18. Interorbital width Lateral line scales Scale rows between dorsal-fin origin and lateral line Scale rows between anal-fin origin and lateral line Predorsal median scales Branched dorsal-fin rays Branched anal-fin rays Branched pelvic-fin rays Pectoral-fin rays Vertebrae A 47.7 59.7 44.0 24.8 47.5 57.9 31.0 28.1 32.8 12.6 20.0 15.6 23.9 18.9 25.8 45.0 26.2 32.7 30.4 36 4 3 9 8 10 6* 11 35 B Morphometrics 44.4-62.3 59.5-64.8 44.5-48.3 22.8-24.8 47.6-51.3 54.3-57.7 29.6-33.0 26.9-30.4 33.1-35.9 11.3-13.0 18.2-22.2 13.9-16.9 19.4-25.4 16.5-20.5 24.1-26.6 45.7-50.6 26.9-32.3 25.8-31.7 30.2-34.7 Meristics 36-39 4-5 ' 3 10-12 8 9-113 6-7" 11-135 35-37 C 46.3-60.0 61.2-65.0 44.6-49.9 24.1-27.3 49.1-52.8 52.3-56.4 32.0-32.6 30.2-31.2 34.9-36.0 12.6-13.2 20.4-21.9 15.8-16.1 21.9-23.5 18.1-18.4 25.2-28.5 45.7-50.1 27.2-29.9 28.6-31.7 29.1-31.3 38 4 3 10-11 8-9* 10-11 7 11-12 36-37 'Five scales between dorsal-fin origin and lateral line present in only 1 paratype. 2Nine branched dorsal-fin rays present in only 1 nontype specimen. 3Nine branched anal-fin rays present in only 1 paratype. 4Medial pelvic-fin ray unbranched when 6 branched rays present, branched when 7 branched rays present. 'Thirteen pectoral-fin rays present in only 1 paratype. HL), the interorbital width (29.1%-34.7% of HL), the contact, or near contact, of the ventral margin of the third infraorbital and the horizontal limb of the preopercle, the lack of a distinct spot of dark pigmentation at the base of the middle caudal-fin rays, the vertically rotund humeral mark without a secondary, dorsal patch of pigmentation, the absence of a distinct patch of pigmentation on the dorsal fin, and the lack of a series of dark spots along the midlateral surface of the body distinguishes Creagrutus gyrospilus within the clade formed by Creagrutus and Piabina. DESCRIPTION.—Morphometric and meristic data for Crea- grutus gyrospilus in Table 22. Body relatively deep and com- pressed. Greatest body depth within one or two scale rows an- terior of base of anteriormost dorsal-fm ray. Dorsal profile of head distinctly convex from margin of upper lip to vertical through posterior margin of anterior nares; straight from that point to posterior tip of supraocciptal spine; smoothly convex from that point posteriorly to anterior of dorsal-fin base, or with inflection point or slight hump two to three scale rows posterior of supraoccipital. Profile of body straight and slightly inclined along dorsal-fm base, straight to slightly con- vex from base of posterior dorsal-fin ray to anterior procurrent caudal-fin ray, with slight dorsal inflection comprising sheath scales at adipose-fin base. Ventral profile of head with broadly rounded obtuse angle approximately midway between margin of lower lip and posterior extremity of dentary, slightly convex from that point to isthmus. Ventral profile of body slightly curved from isthmus to pelvic-fin insertion; then concave from anteriormost anal-fin ray to anterior ventral procurrent caudal- fin ray. Anterior profile of head rounded in lateral view. Upper jaw longer than, and overhanging, lower jaw by distance about equal to up to one-half of orbital diameter. Anterior portion of snout relatively soft and fleshy, with concentration of soft tis- sues; minute papillae concentrated on snout and upper lip, con- tinuing into mouth on fleshy flaps and plicae extending be- NUMBER6I3 115 ^ . FIGURE 45.—Creagrutus gyrospilus, new species, holotype, INHS 69479, 47.7 mm SL; Venezuela, Portuguesa, Rio Saguaz, Rio Guanare-Apure drainage, bridge near park on road to Chabasquen (=Paraiso de Chabasquen; 9°23'30"N, 70o00'30"W). tween outer and medial premaxillary teeth. Lower jaw distinctly fleshy anteriorly, with concentrated papillae. Inner surfaces of lower lip convolute and papillose, with fleshy flaps extending into mouth. Concentrations of papillae also present over lower jaw, isthmus, and cheek. Elements of infraorbital series somewhat reduced, with ven- tral margin of third infraorbital usually contacting, or nearly contacting, ventral limb of preopercle. Posterior and postero- ventral margins of third infraorbital separated from vertical limb of preopercle by gap equal to at most one-half width of third infraorbital; posterior and posteroventral margin of in- fraorbital series describing broad arc approximately concentric with margin of orbit. Premaxillary teeth in three distinct series: primary series arched, with 6 weakly tricuspidate teeth, without pronounced gap between first and second of series, lateral cusps of anterior 4 teeth usually indistinct; triangular cluster of 3 large tricuspi- date teeth, posterior 2 teeth largest and with most highly devel- oped cusps; and single outer weakly tricuspidate tooth posi- tioned approximately lateral to fourth tooth in primary premaxillary series. Maxilla usually with 3 or 4, rarely 2, tri- cuspidate teeth. Dentary with 5 or 6 unicuspidate or tricuspi- date teeth; anterior two teeth largest and with most highly de- veloped secondary cusps, third tooth smaller than first two teeth, with cusps less prominent; 2 or 3 posteriormost teeth rel- atively small, with weakly developed cusps. Dorsal-fin rays ii,8 in most individuals, ii,9 in one nontype specimen. Dorsal-fin origin at, or slightly posterior of, vertical through pelvic-fin origin. Distal margin of dorsal fin slightly concave as result of elongation of second unbranched ray, ante- rior three branched rays, and posterior two branched rays. Anal-fin rays ii-iii,9-l 1; 9 branched rays less common. Anal- fin hooks, when present, occurring on anteriormost 2 or 3 branched rays. Distal margin of anal fin slightly sigmoidal, with second unbranched and anterior 3 branched rays forming variously developed slightly elongate lobe, outline of posterior 5 or 6 branched rays concave. Pectoral-fin rays i, 10-12, 12 branched rays less common. Pectoral fin short in some individ- uals, reaching to within two scale rows of pelvic-fin origin, longer in presumptive males (as indicated by presence of pel- vic- and anal-fin ray hooks) and reaching to, or nearly reach- ing, pelvic-fin base. Pelvic-fin rays i,6,i or i,7. Pelvic-fin hooks, when present, located on medial surfaces of segmented and unsegmented portions of main shaft and medial and branches of all rays medial of the lateral unbranched element; additional weak hooks present on medial surfaces of lateral secondary branches of medial 3 or 4 rays. Tip of pelvic fin not reaching anal-fin origin in males (as indicated by presence of pelvic- and anal-fin ray hooks); in other specimens tip of pelvic fin reaching within 1 or 2 scale rows of that point. Scales on posterior margin of body generally smoothly rounded. Gill rakers 5-8+ 9-11. COLORATION IN ALCOHOL.—Overall pigmentation dusky, with well-developed dark humeral spot and lateral stripe; ground color light brown, with chromatophores ranging from dark brown over much of body to nearly black in areas of higher concentration. Dorsal surface of head with high concen- tration of small, dark brown, punctate chromatophores, chro- matophores most concentrated over snout and medial portions of upper lip, including vertical crescent-shaped area immedi- ately anterior of anterior nares. Pigmentation continuing poste- riorly across interorbital area, covering frontal fontanel. Patch of scattered, dark chromatophores extending laterally from snout along dorsal portion of maxilla. Dorsal surface of parietal portions of cranium and area immediately dorsal of eye pig- mented with scattered, relatively large, dark brown, stellate chromatophores. Band of small, dark brown chromatophores extending from immediately lateral of nares posteroventrally and continuing around ventral and posterior margins of orbit. Dark, stellate chromatophores scattered over dorsal half of 116 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY opercle in region posterior to orbit. Lower lip and ventrolateral surface of head unpigmented. Body pigmentation most concentrated in region dorsal of lat- eral line; pigmentation in form of broad vertical crescents in as- sociation with anteriormost exposed portion of each scale. Scattered, very dark chromatophores present along dorsal mid- line, especially well developed along anterior half of predorsal area, in region immediately lateral of dorsal-fin base, and along middorsal area between dorsal and adipose fins. Humeral mark rounded to somewhat vertically ovoid blotch located in lateral line scale row and scale row immediately dorsal to it. Pigmen- tation on lateral surface of body ventral to lateral line, other than for that associated with humeral spot, mostly restricted to small, dark chromatophores delineating hypaxial myosepta im- mediately dorsal of anal-fin base. Midlateral body stripe rela- tively diffuse anteriorly, becoming denser and somewhat wider approximately at vertical through dorsal-fin origin and extend- ing well ventral of lateral line and posteriorly onto caudal pe- duncle. Intensity of midlateral stripe pigmentation greatest in region from directly ventral of dorsal fin posteriorly to area overlying hypurals. Dorsal-fin membranes with small number of moderately dark chromatophores associated with distal one-half of second unbranched and anterior 5 or 6 branched rays; basal portions of shafts of all, or nearly all, fin rays with scattered, dark chro- matophores. Anal fin mostly unpigmented, with dark chro- matophores located along bases of each ray along approxi- mately anterior one-half of its length. Small, nearly black chromatophores scattered over distal portions of anal-fin ray membranes. Caudal-fin rays delineated by small, dark chro- matophores, with greatest concentrations along dorsalmost rays and over much of ventral lobe. Darkest caudal-fin pigmentation confined to proximal portions of central 4 branched rays, ap- pearing as small, interrupted, slightly horizontally elongate dark spot. Pectoral-fin pigmentation confined to dark line of chromatophores along lateral unbranched ray and in associa- tion with up to four adjacent branched rays. Pelvic fin hyaline. ETYMOLOGY.—The specific name, gyrospilus, from the Latin gyro, meaning circular, and spilus, meaning spot, in ref- erence to the form of the humeral spot in the species. ECOLOGY.—The type locality (INHS 69479, INHS 51282, and USNM 359486) and the locality from which the nontype specimens (INHS 61329) originated were both clear rocky streams with considerable current. DISTRIBUTION.—Creagmtus gyrospilus is known only from two localities in the western portions of the Rio Orinoco basin (Figure 43, solid stars). COMPARISONS.—Creagrutus gyrospilus is most similar to the sympatric C. taphorni with respect to body shape, meristic character values, and the relative development of the infraor- bital series. The two species differ, however, in the form of the humeral mark (compare Figures 45 and 88). Other similar spe- cies, occurring in other drainage systems, include C. crenatus and C. lassoi, which have vertically elongate humeral marks contrary to the rounded mark in C. gyrospilus. These species also differ in various meristic and morphometric features. REMARKS.—The species, which we herein recognize as Cre- agrutus gyrospilus, represents a component of the variation re- ported for C. cf. beni by Taphorn (1992:18, 167), who noted that the humeral mark is usually a rounded blotch, but in some specimens extended above and below the region of the lateral line. The results of our studies indicated that the material iden- tified as Creagrutus cf. beni by Taphorn (1992) included both C. taphorni. which has a vertically elongate humeral mark, and C. gyrospilus, which has a noticeably rounded humeral mark. MATERIAL EXAMINED.—77 specimens (44,44.4-62.3). HOLOTYPE.—VENEZUELA. Portuguesa: Rio Saguaz, Rio Guanare-Apure drainage, bridge near park on road to Cha- basquen (=Paraiso de Chabasquen; 9°23'30"N, 70°00'30"W), collected by D.C. Taphorn et al., 16 Jan 1986, INHS 69479, 1 (47.7; male). PARATYPES.—40 specimens (40, 44.4-62.3). VENEZUELA. Portuguesa: Rio Saguaz, Rio Guanare-Apure drainage, bridge near park on road to Chabasquen (^Paraiso de Chabasquen; 9°23'30"N, 70°00'30"W), collected with holo- type, INHS 51282, 32 (48.6-62.3); USNM 359486, 8 (44.4- 61.6). NONTYPE SPECIMENS.—36 specimens (3,46.3-60.0). VENEZUELA. Barinas: Tributary of Rio Santo Domingo, Rio Apure drainage, 10 km NW Barinitas (latter locality at 8°45'N, 70°45'W), INHS 61329, 6 (3, 46.3-60.0). Lara: Rio Claro, in town of Rio Claro (9°55'30"N, 69°21'20"W), MCNG 13392,30. Creagrutus holmi, new species FIGURES 43,46, TABLE 23 Creagrutus beni [not of Eigenmann, 1911].—Pearson, 1937a:92 [misidentifi- cation] [Peru (Departmento Cajamarca): Balsas, Tingo de Pauca on Rio Ma- ranon, Paipay on Rio Crisnejas]. DIAGNOSIS.—The combination of the possession of premax- illary dentition arranged in the three components generalized for most of the species of Creagrutus and Piabina without a distinctly larger gap between the first and second teeth of the primary series, 3 to 5 teeth on the maxilla, 6, very rarely 5, teeth in the primary tooth row of the premaxilla, 5 dentary teeth, 37 to 40 lateral line scales without a lamellar process over each pore, 9 to 11 predorsal median scales, 4 scale rows between the dorsal-fin origin and the lateral line, 36 to 38 ver- tebrae, 9 to 11 branched anal-fin rays, 2 post-anal median scales to the anal-fin origin, 6 to 8 gill rakers on the upper limb of the first gill arch, 9 to 12 gill rakers on the lower limb of the first gill arch, the distance from the dorsal-fin origin to the anal-fin origin (32.2%-38.5% of SL), the postorbital head length (43 .9%-50 .0% of HL), the interorbital width (28.6%-34.5% of HL), the well-developed third infraorbital closely approaching or contacting the horizontal limb of the preopercle in larger individuals, the lack of a series of dark NUMBER 613 117 TABLE 23.—Morphometrics and meristics of Creagrutus holmi. new species: (A) holotype of C. holmi. MUSM 5670; and (B) paratypes of C. holmi (n=38). Standard length is expressed in mm; measurements 1 to 14=percentages of standard length; 15 to 18=percentages of head length. Characters Standard length 1. Snout to anal-fin origin 2. Snout to pelvic-fin insertion 3. Snout to pectoral-fin insertion 4. Snout to dorsal-fin origin 5. Dorsal-fin origin to hypural joint 6. Dorsal-fin origin to anal-fin origin 7. Dorsal-fin origin to pelvic-fin insertion 8. Dorsal-fin origin to pectoral-fin insertion 9. Caudal peduncle depth 10. Pectoral-fin length 11. Pelvic-fin length 12. Dorsal-fin length 13. Anal-fin length 14. Head length 15. Postorbital head length 16. Snout length 17. Bony orbital diameter 18. Interorbital width Lateral line scales Scale rows between dorsal-fin origin and lateral line Scale rows between anal-fin origin and lateral line Predorsal median scales Branched dorsal-fin rays Branched anal-fin rays Branched pelvic-fin rays Pectoral-fin rays Vertebrae A B Morphometrics 81.9 66.4 48.0 23.7 47.9 56.5 34.7 35.3 34.8 11.7 20.0 15.1 20.7 17.2 25.3 46.9 28.5 29.3 30.9 45.1-92.0 62.6-69.4 45.0-52.1 22.2-26.5 45.5-50.4 54.1-60.1 32.2-38.5 28.1-35.4 32.5-36.4 11.5-13.7 18.5-23.4 14.9-20.0 20.6-24.5 17.0-20.7 24.0-28.3 43.9-50.0 24.6-30.5 29.2-34.1 28.6-34.5 Meristics 39 4 3 10 8 10 6 13 37 37-40 4' 3 9-11 8 9-11 62 12-14 36-38 'Five scales between dorsal-fin origin and lateral line present in only 1 non- type specimen. 2Five branched rays present in 1 nontype specimen and 7 branched rays present in 3 nontype specimens. midlateral spots on the body, the possession of a diffuse, verti- cally elongate rotund humeral spot, the lack of a distinct dark spot at the base of the middle caudal-fin rays, and the absence of a discrete patch of dark pigmentation on the middle portion of the anterior dorsal-fin rays distinguishes Creagrutus holmi within the clade composed of Creagrutus and Piabina. DESCRIPTION.—Morphometric and meristic data for Crea- grutus holmi in Table 23. Head and body robust, body propor- tionally more robust in larger individuals of some populations and in females with well-developed ovaries. Greatest body depth at dorsal-fin origin in most specimens, shifted slightly anterior of that point in ripe females. Dorsal profile of head convex from tip of snout to vertical through posterior nostril, straight or slightly convex anteriorly from that point to tip of supraoccipital spine. Interorbital region distinctly convex. Dor- sal profile of body gently curved, with anterior portion continu- ing alignment of profile of rear portion of head in specimens up to approximately 45 mm SL, more convex with distinct change in alignment relative to that of head in many larger individuals. Dorsal surface of body with obtuse median ridge between tip of supraoccipital spine and dorsal-fin origin. Ventral profile of head with obtuse, but distinct, angle at anteroventral corner of dentary, profile ranging from nearly straight to gently convex from that point to isthmus. Ventral profile of body ranging from slightly to distinctly convex, latter condition typical of ripe females. Prepelvic region of body obtusely flattened trans- versely. Head obtusely rounded in both lateral and dorsal views. Up- per jaw longer than, and overhanging, lower jaw. Snout slightly fleshy anteroventrally with scattered papillae anteriorly. Upper lip fleshy, with papillae along anterior and ventral margins; pa- pillae continue onto plicae extending between outer and medial premaxillary teeth. Lower lip moderately fleshy with papillae moderately concentrated along dorsal surface and with scat- tered papillae anteroventral ly. Infraorbital series moderately developed overall. Third in- fraorbital well developed; ventral margin falling distinctly short of horizontal limb of preopercle in specimens of up to ap- proximately 50 mm SL, but approaching, or in contact with, that bone in larger individuals. Posterior margins of third through fifth infraorbitals falling short of vertical limb of preo- percle. Premaxillary dentition in three series: primary series with 6, very rarely 5, teeth arranged in curved or very slightly sigmoid arch without pronounced gap between first and second tooth of series but with median tooth distinctly separated from its con- tralateral tooth; triangular cluster of 3 somewhat larger teeth; and single tooth of form similar to that of primary series lying lateral to fourth tooth, or to space between third and fourth teeth, of primary premaxillary series. Maxilla with 3 to 5 tri- cuspidate teeth. Dentary with 5 tricuspidate teeth; first and sec- ond teeth distinctly larger than others and subequal, somewhat less than twice height of third tooth; fourth and fifth teeth dis- tinctly smaller than anterior teeth and compressed. Dorsal-fin rays ii,8 in all specimens. Dorsal-fin origin ap- proximately at vertical through pelvic-fin insertion. Profile of distal margin of dorsal fin ranging from straight to very slightly concave. Anal-fin rays ii ,9-ll , rarely iii,10. Profile of distal margin of anal fin straight to very slightly concave with ante- rior rays forming barely obvious lobe. Anal-fin hooks present in relatively few of examined specimens, perhaps reflecting pronounced seasonality in their presence in mature males; hooks, when present, limited to anterior 2 or 3 branched anal- fin rays. Pectoral-fin rays i, 11 — 13. Tip of pectoral fin extending posteriorly slightly beyond three-fourths of distance to pelvic- fin insertion. Pelvic-fin rays most commonly i,6,i, but one specimen with i,5.i and another with i,7. Tip of pelvic fin ex- tending posteriorly approximately 1 scale short of anus. Pelvic- fin hooks present in relatively few of the examined specimens, perhaps reflecting pronounced seasonality in their presence in mature males; hooks, when present, located on all branched pelvic-fin rays. 118 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY Gill rakers 6-8 + 9-12. COLORATION IN LIFE.—(Descriptions based on slides of re- cently captured specimens provided by E. Holm, ROM). Ground coloration ranging from tan to purplish gray. Guanine covering scales more obvious over midlateral body stripe in smaller specimens. Midlateral body stripe obvious, but more pronounced in specimens with darker overall pigmentation. Humeral mark variably obvious, most distinct in some speci- mens with lighter overall head and body coloration. Caudal fin with reddish tint on rays in some specimens. Anterior rays of anal fin sometimes white. COLORATION IN ALCOHOL.—Ground coloration of speci- mens light tan. Dorsal surface of head with dense field of small, dark chromatophores extending anteriorly onto snout, upper lip, and region anterior to orbit. No indication of deep-ly- ing dark chromatophores overlying brain. Variably denser con- centration of dark chromatophores anterior to nostrils forming crescent-shaped patch. Posterior margin of maxilla and adjoin- ing region of snout with somewhat increased concentration of dark chromatophores. Chromatophore concentration somewhat greater anteroventral of orbit, but without discrete pattern of chromatophores surrounding ventral and posterior margins of orbit as occurs in some congeners. Scattered, dark, surface chromatophores located ventral and posterior of orbit. Variably present denser concentration of dark chromatophores on mid- dle of opercle, with scattered chromatophores on dorsal portion of opercle. Scales of dorsolateral portion of body with field of dark chromatophores on basal portion of exposed scales and along distal margins, with chromatophore fields on each scale sepa- rated by hyaline region. Midlateral body stripe formed of deep- lying chromatophores extending from slightly posterior of hu- meral mark to posterior portion of caudal peduncle. Humeral mark vertically elongate, but variable in both intensity and form. Mark ranges from barely obvious, vertically elongate patch of chromatophores merging into surrounding pigmenta- tion to obvious but diffuse dark patch. Some specimens with central region of humeral mark distinctly darker. Darker central region of mark in such specimens with less pronounced fields of chromatophores extending from dorsal and ventral margins. Dorsal portion of humeral mark arched somewhat anteriorly, with anterodorsal section forming distinct anterior process. Ventral portion of mark typically ventrally tapering. Dorsal fin with rays outlined by small dark chromatophores and with fields of chromatophores over distal one-half of fin membranes. Anal fin with basal one-half to three-fourths of fin rays outlined by dark chromatophores. Caudal fin somewhat dusky. Pectoral and pelvic fins hyaline or with few scattered chromatophores. ETYMOLOGY.—The species name, holmi, is in honor of Er- ling Holm of the Royal Ontario Museum, Toronto, who col- lected many of the specimens that served as the basis for the species description along with numerous other series of Crea- grutus specimens valuable to this study and who has been of great assistance to the authors in this and other studies. ECOLOGY.—The collection locality for the majority of the paratypes of Creagrutus holmi (MUSM 8866, ROM 55331, USNM 341369) was at an elevation of 850 m in a rapidly flow- ing (1 m/sec), 5 m wide, clear water stream over a substrate composed predominantly of boulders (30%), rubble (30%), and gravel (30%), with the remainder sand (10%). The habitat was approximately 90% riffles and the remainder was pools. The canopy over the water was 80% partially open and the rest was totally open. One other sample (ROM 52247) came from gen- erally comparable habitats, although one lot (ROM 52248) came from an area with silt bottoms and only 10% riffles. Cre- agrutus holmi appears to be limited to upland regions with the reported elevations ranging between 800 and 1158 m. Stomach content analysis of four specimens prepared for clearing and staining in this study showed that the species had been feeding on seeds, larval insects, and in one case on a small characid. DISTRIBUTION.—Creagrutus holmi is limited to the Rio Ma- ranon basin above Pongo de Manseriche, in northeastern Peru (Figure 43). COMPARISONS.—This is the only Creagrutus species known from the Rio Maranon basin, and it achieves some of the high- est elevations of any member of the genus. GEOGRAPHIC VARIATION.—Although this species has a rela- tively limited distributional range, there is a notable, but con- tinuous, degree of variation between different population sam- ples. Some specimens collected in the Rio Utcubamba basin are somewhat deeper bodied than those from some other locali- ties, with, however, a notable degree of overlap with the range of values for this feature in other population samples. The hu- meral mark also shows notable variation in intensity among ex- amined specimens, ranging from being effectively absent to very distinct. To a degree, this variation is a function of the size of the specimens, but the features demonstrate a considerable range within and between population samples. Despite this variation, we did not discover any discrete differences that would justify the recognition of more than one species within the material that is herein identified as Creagrutus holmi. REMARKS.—Pearson (1937a:92) reported Creagrutus beni from several locations in the upper Rio Maranon valley in the southern portions of the Department of Cajamarca, Peru. Ex- amination of material from two of the three localities (Balsas, USNM 167816, formerly IU 17600; Tingo de Pauca, CAS 69292, formerly IU 17601) has shown that it is C. holmi rather than C. beni. Creagrutus beni, as delimited in this study, is en- demic to northern Bolivia and southeastern Peru, a region dis- tant from the known distribution of C. holmi. Although speci- mens from Paipay, the third locality in the upper Rio Maranon valley cited by Pearson (1937a:92), have not been examined, C. holmi is the only Creagrutus species discovered during this study in that river system. Thus, all of Pearson's (1937a) records of C. beni are considered herein to refer to C. holmi. NUMBER 613 119 FIGURE 46.—Creagrutus holmi, new species, holotype, MUSM 5670, 81.9 mm SL; Peru, Amazonas, Provincia Utcubamba, Bagua Grande, San Antonio, Quebrada Jaimito (approximately 5°47'S, 78°23'W). MATERIAL EXAMINED.—315 specimens (97, 39.8-92.0). HOLOTYPE.—PERU. Amazonas: Provincia Utcubamba, Ba- gua Grande, San Antonio, Quebrada Jaimito (approximately 5°47'S, 78°23'W), collected by P. Baltazar, 14 Apr 1988, MUSM 5670, 1 (81.9). PARATYPES.—38 specimens (38, 45.1-92.0). PERU. Amazonas: Provincia Utcubamba, Bagua Grande, San Antonio, Quebrada Jaimito (approximately 5°47'S, 78°23 'W), collected with holotype, MUSM 8865, 7 (45.1-59.5); USNM 341368, 6 (47.2-76.5; 1 specimen cleared and counterstained for cartilage and bone). Cajamarca: Tribu- tary to Rio Huancabamba, approximately 74 km W of road go- ing N to Jaen, between Pucara and Guabel (approximately 5°56'S, 79°15'W), collected by E. Holm and J. Patalas, 8 Jul 1986, MUSM 8866, 5 (51.3-80.7); USNM 341369, 5 (53.5-92.0); ROM 55331, 5 (45.3-91.7); ROM 72379, 10 (61.5-85.8). NONTYPE SPECIMENS.—276 specimens (58, 39.8-91.7). PERU. Amazonas: Quebrada Pusac, Huancabamba, approx- imately 16 km by road upstream from Balsas (approximately 6°53'S, 78°01'W), ROM 52247, 10 (39.8-85.2). Balsas (6°50'S, 78°01'W), at 3500 ft (=1067 m), USNM 167816, 7 (41.5-64.5; formerly IU 17600, in part; 3 specimens cleared and stained for bone). Tingo de Pauca, at mouth of Rio Crisne- jas into Rio Maranon (7°21'S, 77°50'W), at approximately 3800 ft (=1158 m), CAS 69292, 12 (formerly IU 17601). Trib- utary of Rio Maranon, at Tsutshunha, near Tutumbertos, down- stream from Aramango, at Aguarani Indian Village, ROM 55328, 17 (10, 46.4-66.3). Rio Santiago basin, 1 km from Caterpiza (latter locality at approximately 3°55'S, 77°42'W), LACM 41991-7, 6 (63.6-88.7). Rio Santiago basin, 3 km from Caterpiza (latter locality approximately 3°55'S, 77°42'W), LACM 41993-13, 5 (44.5-76.8). Quebrada Pastazillio (not lo- cated), LACM 39337-9, 7 (40.9-67.0). Rio Cenepa, vicinity of Huampani (4°28'S, 78°10'W), LACM 36357-53, 2 (1 , 74.0). Rio Cenepa basin, Rio Huampani, at Huampani (approximately 4°28'S, 78°10'W), LACM 39645-5, 5 (64.9-65.8). Rio Cenepa basin, Chigkan entse (=Quebrada Chigkan; approximately 4°28'S, 78°11'W), LACM 39681-2, 1 (80.7). Rio Maranon, few km upstream from Puerto Balsas (6°51'S, 78°02'W), ROM 55326, 3 (1 , 59.0). Rio Maranon, 14 km upstream from Balsas (6°57'S, 78°01'W), ROM 52248, 17. Cajamarca: Tributary to Rio Huancabamba, approximately 74 km W of road going N to Jaen, between Pucara and Guabel (approximately 5°56'S, 79°15'W), ROM 55331, 5 (45.3-91.7), ROM 52252, 179. Creagrutus hysginus Harold, Vari, Machado-AUison, and Provenzano, 1994 FIGURES 43,47, TABLE 24 Creagrutus beni [not of Eigenmann, 1911].—Fowler, 1931:408 [misidentifica- tion] [Venezuela (Sucre) Yarapa River].—Beebe, 1945:84 [Venezuela, Mona- gas, Rio San Juan basin, south of Caripito; survival in drying stream; life col- oration].—Marrero and Machado-AUison, 1990:66 [in part, citation of Fowler, 1931:408 in synonymy].—Taphom et al., 1997:71 [cited for Venezu- ela], Creagrutus hysginus Harold et al., 1994:975, fig.l [type locality: Venezuela, Estado Sucre, Rio Giiiria, near La Toma]. DIAGNOSIS.—The combination of the possession of premax- illary dentition arranged in the three components generalized for most of the species of Creagrutus and Piabina without a distinctly larger gap between the first and second teeth of the primary series, 4 or 5 teeth on the maxilla, 6 teeth in the pri- mary series of the premaxilla, 6 dentary teeth, 35 to 38 lateral line scales without a lamellar process over each pore, 9 to 11 predorsal median scales, 5 scale rows between the dorsal-fin origin and the lateral line, 36 or 37 vertebrae, 9 or 10 branched anal-fin rays, 2 post-anal median scales to the anal-fin origin, the distance from the dorsal-fin origin to the pelvic-fin inser- tion (27.5%—33.1% of SL), the distance from the dorsal-fin ori- gin to the pectoral-fin insertion (32.1%—36.8% of SL), the cau- dal peduncle depth (10.7%-12.9% of SL), the head length (27.3%-30.8% of SL), the length of the postorbital portion of head (44.1 %-52.6% of HL), the snout length (21.1 %-28.8% of HL), the moderately developed third infraorbital distinctly sep- 120 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY TABLE 24.—Morphometrics and meristics of Creagrutus hysginus: (A) holo- lype of C. hysginus, MBUCV V-20310; and (B) all other specimens of C. hys- ginus from which counts and measurements were taken (n=28). Standard length is expressed in mm; measurements 1 to 14=percentages of standard length; 15 to 18=percentages of head length. Characters Standard length 1. Snout to anal-fin origin 2. Snout to pelvic-fin insertion 3. Snout to pectoral-fin insertion 4. Snout to dorsal-fin origin 5. Dorsal-fin origin to hypural joint 6. Dorsal-fin origin to anal-fin origin 7. Dorsal-fin origin to pelvic-fin insertion 8. Dorsal-fin origin to pectoral-fin insertion 9. Caudal peduncle depth 10. Pectoral-fin length 11. Pelvic-fin length 12. Dorsal-fin length 13. Anal-fin length 14. Head length 15. Postorbital head length 16. Snout length 17. Bony orbital diameter 18. lnterorbital width Lateral line scales Scale rows between dorsal-fin origin and lateral line Scale rows between anal-fin origin and lateral line Predorsal median scales Branched dorsal-fin rays Branched anal-fin rays Branched pelvic-fin rays Pectoral-fin rays Vertebrae A B Morphometrics 44.9 66.4 50.9 27.7 51.2 54.3 33.2 31.1 36.0 11.7 19.5 16.2 22.5 19.2 29.9 49.0 25.5 32.5 28.2 30.3-55.6 61.7-67.5 46.9-51.6 26.7-31.9 48.1-54.6 51.4-56.9 28.3-33.4 27.5-33.1 32.1-36.8 10.7-12.9 18.1-22.5 15.1-17.0 19.8-24.5 14.8-20.4 27.3-30.8 44.1-52.6 21.1-28.8 28.5-36.1 25.7-35.0 Meristics 37 5 3 10 8 10 7 12 36 35-38 5 3^* 9-11 8 9-10 7 11-12 36-37 arated from the horizontal limb of the preopercle, the lack of a series of dark midlateral spots on the body, the absence of a dis- tinct spot of dark pigmentation on the basal portions of the middle caudal-fin rays, the rotund to slightly vertically elon- gate humeral mark, and the absence of a discrete patch of dark pigmentation on the middle portion of the anterior dorsal-fin rays distinguishes Creagrutus hysginus within the clade com- posed of Creagrutus and Piabina. The brilliant red life coloration of the adipose fin of C. hysgi- nus is not known to occur in any of the few other Creagrutus species for which we have life coloration information. Further life coloration information is necessary to determine whether such adipose-fin pigmentation is unique to, and thus an autapo- morphy for, C. hysginus. DESCRIPTION.—Morphometric and meristic data for Crea- grutus hysginus in Table 24. Body slightly rotund abdominally in profile compared with most species in the genus. Maximum body depth approximately one-half of distance between inser- tions of pectoral and pelvic fins. Anterior profile of snout and dorsal profile of head meeting in rounded obtuse angle near vertical through point midway between nares. Dorsal profile of head posterior to that line inclined and straight to slightly con- vex. Predorsal profile of body with notable change in align- ment relative to that of head, asymmetrically convex, with con- vexity most pronounced in anterior one-third of region but with some specimens (e.g., holotype, Figure 47) having pronounced curvature immediately posterior to occiput; presence of pro- nounced curvature not related to sex. Dorsal profile of body straight between dorsal-fin origin and caudal peduncle. Ventral profile of head and body slightly convex from anterior margin of lower jaw to pelvic-fin origin, or with ventral surface of head and abdomen each with distinctly rounded profile. Rounded obtuse angle delimiting anteroventral angle of den- tary, angle variably apparent among specimens depending on state of preservation. Upper jaw longer than, and overhanging, lower jaw. Anterior surface of snout fleshy, with numerous minute papillae over surface; greatest concentration of papillae on upper lip, margin of upper jaw, and in mouth on fleshy flaps and plicae extending between outer and medial premaxillary teeth. Lower lip with thick, fleshy anterior region and numerous papillae on antero- dorsal surface. Infraorbital series moderately well developed, covering ap- proximately two-thirds of cheek. Ventral margin of third in- fraorbital separated from horizontal limb of preopercle by space equal to approximately one-half width of that infraor- bital. Curvature of posteroventral margin of third infraorbital approximately concentric with margin of orbit. Third through fifth infraorbitals distinctly separated posteriorly from vertical limb of preopercle. Premaxillary dentition in three series: primary series straight, consisting of 6 tricuspidate teeth with rounded to well-devel- oped cusps, without pronounced gap between first and second tooth of series; triangular cluster of 3 larger teeth with medial- most tooth asymmetrical and nearly contacting contralateral tooth of other side; and single tooth similar in form to those of primary premaxillary row, occurring lateral to fourth tooth of primary series. Maxilla with 4 or 5 tricuspidate teeth. Dentary 6 tricuspidate teeth; anterior 3 teeth largest, second tooth about one-third higher than first tooth and nearly twice as high as third tooth; following teeth successively shorter and com- pressed. Dorsal-fin rays ii,8. Dorsal-fin origin at vertical through pel- vic-fin origin. Profile of distal margin of dorsal fin with slight concavity. Anal-fin rays ii,9-10 or iii,9-10. Profile of distal margin of anal fin nearly straight, with anterior branched rays slightly elongate. Single, bilaterally paired hooks present on 2 or 3 anterior branched anal-fin rays of mature males (hooks ob- served on only 3 of 20 examined specimens). Mature males with hooks restricted to posterolateral surface of main shaft and posterior, secondary branch of each ray. Pectoral-fin rays i, 11-12. Tip of pectoral fin extending posteriorly to pelvic-fin base in mature males as shown by presence of anal- and pel- vic-fin hooks; other specimens with pectoral fin extending pos- teriorly approximately three-fourths of distance between pecto- NUMBER 613 121 FIGURE 47.—Creagrutus hysginus, holotype, MBUCV V-2O31O, 44.9 mm SL; Venezuela, Sucre, Rio Giiiria, near La Toga. ral- and pelvic-fin insertions. Pelvic-fin rays i,7. Tip of pelvic fin approaching or, especially in well-developed mature males, extending to anal-fin origin; with distal portion turned medially in some individuals, giving fin slightly cupped shape. Pel- vic-fin hooks in mature males, when present, occurring on all portions of all branched rays, except the smallest, distal branches. Gill rakers 5-7 + 8-10. COLORATION IN LIFE.—Adipose fin brilliant red. Less in- tense orange-red pigmentation present in broad horizontal band through central part of dorsal fin and distal portion of outer caudal-fin rays. Lateral 2 or 3 rays of pelvic and pectoral fins pale orange. Anal fin hyaline. Dorsal surface of eye with bright red patch overlying reflective guanine pigment. Based on the collecting locality, it is likely that the specimens cited as Crea- grutus beni by Beebe (1945:84) are C. hysginus. Beebe re- ported that the species was "Greenish-yellow with silvery sheen, two more or less blue body bands; a very broad oxidized silver lateral band ... much of the dorsal, anal and caudal fins is scarlet, as is the iris." Nocturnal coloring was noted by Beebe as "all body pigment bands and most of the red color disappear at night." COLORATION IN ALCOHOL.—Dorsal surface of head with light brown, shallow chromatophores and dark brown to black, deep chromatophores. Deep chromatophores small, punctate, lining interior surfaces of frontal, obscured in midline by con- nective tissue in fontanel. Shallow chromatophores small to large, stellate, present over entire dorsal surface of head, most concentrated on medial one-half of upper jaw and snout, con- tinuing posterolaterally from snout to nares and posterodorsally to point above center of orbit and overlying fontanel. Small crescent of dark pigmentation often present anterior to nares in other Creagrutus species present and continuous with snout pigmentation. Band of scattered, light and dark chromato- phores extending from pigmentation on snout and upper jaw posteriorly across cheek around margin of orbit and almost to distal margin of infraorbital bones, and joining body of scat- tered chromatophores of various sizes posterior to orbit. Scat- tered, large, brown, stellate chromatophores arranged in dors- oventrally elongate band on cheek between infraorbitals and preopercle. Scales of dorsal portion of body with small dark chromato- phores concentrated in area medial to scale center and with larger stellate, lighter chromatophores arranged in arc on lateral surface of posterior field. Overall appearance of dorsal pigmen- tation faintly reticulate, but some specimens having irregularly arranged scales with very darkly pigmented central fields. Small black chromatophores along dorsal midline of body and along margin of dorsal-fin base, forming longitudinal stripe from occiput to caudal peduncle. Humeral mark usually ap- pearing as irregular blotch or rounded mark immediately dorsal to lateral line, but occasionally extending anterodorsally and diffusely, giving overall appearance of inverted comma. Dif- fuse midlateral stripe present, extending posteriorly from area behind humeral mark onto, and slightly expanding on, caudal- fin base. Deep-lying pigmentation of midlateral stripe mostly obscured by overlying guanine in examined specimens. Stripe most sharply defined ventrally and posteriorly. Region of body between midlateral stripe and anal-fin base with very small, dark chromatophores delineating myosepta. Anal-fin base only diffusely pigmented, without dark triangular pigmentation patches present in some congeners. Small, dark chromatophores present on caudal-fin mem- branes; greatest concentration of chromatophores in associa- tion with central rays, appearing as disjunct extension of mid- lateral stripe, and on dorsal and ventral branched rays and procurrent rays. In juveniles (approximately 20-22 mm SL), pigmentation of middle caudal-fin rays concentrated basally and appearing as small spot. Ventral lobe of caudal fin much more densely pigmented overall than dorsal lobe. Small dark chromatophores on distal one-half of anal-fin membranes, some specimens showing great enlargement of these chromato- phores, giving appearance of dark spot in central portion of fin. Diffuse dark pigmentation in narrow bands immediately adja- 122 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY cent to anterior surfaces of basal, unsegmented portions of rays and mainly restricted to narrow bands immediately adjacent to all portions of fin rays. Distal portions of unbranched and ante- rior two branched anal-fin rays unpigmented. Dark chromato- phores of various sizes present across dorsal-fin membranes; pigmentation often darkest and densest in posterior one-half of fin in distal one-half of membrane. Pectoral fin hyaline except for single line of small dark chromatophores on basal one-half of lateral, unbranched ray. Pelvic fin hyaline. ECOLOGY.—Creagrutus hysginus is quite abundant in the Rios Bautista and Giiiria. These are small rivers of crystal-clear water that descend from the mountains of the central Peninsula de Paria, northeastern Venezuela. The substrate of both rivers is coarse, ranging mainly from gravel to large stones with small amounts of sand present. Creagrutus hysginus occurs in fast-flowing current as well as quiescent backwater areas. The surrounding forest contributes large amounts of allochthonous material to the streams, including leaves, flowers and fruit, and terrestrial insects. Examination of gut contents of C. hysginus revealed that the species feeds on this material as well as aquatic dipteran larvae. Beebe (1945:84) reported that C. hysginus (cited as C. beni; see under "Remarks," below) was one of the species surviving in the mixture of damp mud and decaying vegetation at the bot- tom of a drying creek-bed in Rio San Juan basin south of Car- ipito in the state of Monagas, Venezuela. DISTRIBUTION.—The known distribution of Creagrutus hys- ginus is restricted to several rivers draining into the Golfo de Paria in the coastal states of Sucre and Monagas, northeastern Venezuela (Figure 43, diamonds). In the Peninsula de Paria, C. hysginus has been collected in the upland portions of the Rios Bautista, Giiiria, Irapa, and Yoco. Creagrutus species were ab- sent in the 20 collections of freshwater fishes from the lowland region near the base of the peninsula as reported by Fernan- dez-Yepez (1969). The species also occurs in upland tributaries of the Rio San Juan of Sucre and Monagas states that flows into the western portions of the Golfo de Paria. REMARKS.—In a report on fishes collected in Venezuela by L. Wehekind, Fowler (1931:408) attributed material of Crea- grutus hysginus (ANSP 53383-6) to C. beni Eigenmann; how- ever, C. hysginus is distinguished from C. beni by the shape of the humeral mark (essentially round in C. hysginus versus ver- tically elongate in C. beni), the number of branched anal-fin rays (9 or 10 in C. hysginus versus 11 to 13 in C. beni), and the number of vertebrae (36 or 37 in C. hysginus versus 37 to 39 in C. beni). Furthermore, Creagrutus beni, as recognized in this paper, is endemic to the upper portions of the Rio Madeira ba- sin in northeastern Bolivia. Fowler (1931:408) reported Creagrutus beni (material herein ascribed to C. hysginus) from the Rio Yarapa, Estado de Sucre, in eastern Venezuela. We have been unable to locate such a drainage in examined gazetteers or maps, a problem also en- countered by Fernandez-Yepez (1969). On the basis of the date cited by Fowler for the collection of these specimens, and lo- cality and collection-date data of other collections from that ex- pedition reported by Fowler (1931), we conclude that those Creagrutus specimens (ANSP 53383-6) were most likely col- lected in an upland tributary of the Rio San Juan, a tributary of the western portion of the Golfo de Paria. Beebe (1945:84) cited Creagrutus beni from the upper por- tions of the Rio San Juan, perhaps following Fowler (1931). We have been unable to locate the specimens that were the ba- sis for that citation, but given that C. beni is endemic to north- ern Bolivia and southeastern Peru and that C. hysginus is the only Creagrutus species we have examined that originated in the Rio San Juan basin, it is likely that Beebe's citation of C. beni is a misidentification of C. hysginus. MATERIAL EXAMINED.—667 specimens (28, 30.3-55.6). VENEZUELA. Sucre: Rio Giiiria, near La Toga, MBUCV V-20310, 1 (44.9, holotype of Creagrutus hysginus); CAS 79623, 9 (33.2^*3.0, paratypes of Creagrutus hysginus; 1 spec- imen cleared and counterstained for cartilage and bone); MBUCV V-24002, 20 (paratypes of Creagrutus hysginus); USNM 326055, 10 (34.1^4.5, paratypes of Creagrutus hysgi- nus; 2 specimens cleared and counterstained for cartilage and bone); MBUCV V-24003, 186. Rio Bautista, Sector Rio above last Carretera, MBUCV V-20304, 12 (4, 30.3-37.6, paratypes of Creagrutus hysginus; 1 specimen cleared and counterstained for cartilage and bone). Rio La Toga, 6 km N of road 9, approx- imately 4 km W of Guiria, CAS 80270, 10 (paratypes of Crea- grutus hysginus); MCNG 19691, 148 (paratypes of Creagrutus hysginus); USNM 326035, 10 (paratypes of Creagrutus hysgi- nus; two specimens cleared and counterstained for cartilage and bone). Rio Yarapa (locality uncertain; see comments under "Remarks," above), ANSP 53383-6, 4 (45.4-55.6; 1 specimen cleared and counterstained for cartilage and bone). Rio Guiria, NE of Guiria, MBUCV V-20288, 3. Rio Yoco, sector Chaguaramas, NW of Yoco, MBUCV V-20295, 25. Rio Irapa, MCNG 16174, 5. Rio Guiria, west of Guiria, MCNG 16768, 5. Cano E of Campo Claro, MCNG 16776, 21. Rio Yoco, near Guiria, MHNLS 9715, 14. Quebrada El Mango, tributary to Rio Capiricual (Rio San Juan system), MHNLS 9832, 31. Monagas: Rio Cocollar, Rio Guarapiche tributary (Rio San Juan system), MHNLS 9830, 7. Rio Capiricual, tributary to Rio Guarapiche (Rio San Juan system), S of El Arbolito, MHNLS 9831, 146. Creagrutus ignotus, new species FIGURES 43,48, TABLE 25 DIAGNOSIS.—The combination of the possession of premax- illary dentition arranged in the three components generalized for most of the species of Creagrutus and Piabina without a distinctly larger gap between the first and second teeth of the primary series, 2 or 3 teeth on the maxilla, 6, very rarely 5, teeth in the primary tooth row of the premaxilla, 6 dentary teeth, 37 to 40 lateral line scales without a lamellar process over each pore, 9 to 11 predorsal medianscales, 4 scale rows between the dorsal-fin origin and the lateral line, 36 to 38 ver- tebrae, 9 to 11 branched anal-fin rays, 2 post-anal median NUMBER 613 123 TABLE 25.—Morphometrics and meristics of Creagrutus ignotus, new species: (A) holotype of C. ignotus, MZUSP 45310; and (B) paratypes of C. ignotus (n=14). Standard length is expressed in mm; measurements 1 to I4=percent- ages of standard length; 15 to 18 = percentages of head length. Characters Standard length 1. Snout to anal-fin origin 2. Snout to pelvic-fin insertion 3. Snout to pectoral-fin insertion 4. Snout to dorsal-fin origin 5. Dorsal-fin origin to hypural joint 6. Dorsal-fin origin to anal-fin origin 7. Dorsal-fin origin to pelvic-fin insertion 8. Dorsal-fin origin to pectoral-fin insertion 9. Caudal peduncle depth 10. Pectoral-fin length 11. Pelvic-fin length 12. Dorsal-fin length 13. Anal-fin length 14. Head length 15. Postorbital head length 16. Snout length 17. Bony orbital diameter 18. Interorbital width Lateral line scales Scale rows between dorsal-fin origin and lateral line Scale rows between anal-fin origin and lateral line Predorsal median scales Branched dorsal-fin rays Branched anal-fin rays Branched pelvic-fin rays Pectoral-fin rays Vertebrae A B Morphometrics 41.1 66.2 51.8 25.3 48.9 54.7 29.4 22.1 29.2 9.5 19.5 17.0 19.3 16.7 27.7 43.9 32.5 30.7 25.4 26.8-41.8 61.3-65.9 45.0-51.9 23.8-26.7 46.3-49.6 52.9-55.4 26.9-30.5 21.5-25.4 28.5-31.7 9.3-11.0 18.6-22.4 14.9-17.5 18.7-21.3 14.5-18.0 24.9-28.9 36.8^*5.8 28.7-33.9 30.4-34.9 25.3-28.9 Meristics 38 4 3 11 8 11 6 12 36 37-40 4 3 9-11 8 9-11 6 11-13 36-38 scales to the anal-fin origin, 6 to 8 gill rakers on the upper limb of the first gill arch, 9 to 11 gill rakers on the lower limb of the first gill arch, the distance from the dorsal-fin origin to the hy- pural joint (52.9%-55.4% of SL), the distance from the dorsal- fin origin to the anal-fin origin (26.9%-30.5% of SL), the dis- tance from the dorsal-fin origin to the pelvic-fin insertion (21.5%-25.4% of SL), the distance from the dorsal-fin origin to the pectoral-fin insertion (28.5%-31.7% of SL), the caudal peduncle depth (9.3%-11.0% of SL), the interorbital width (25.3%-28.9% of HL), the well-developed third infraorbital contacting the horizontal limb of the preopercle in larger speci- mens, the lack of a series of dark midlateral spots on the body, and the slightly anterodorsally arched, vertically elongate hu- meral mark without straight anterior and posterior margins dis- tinguishes Creagrutus ignotus from all species within the clade composed of Creagrutus and Piabina. DESCRIPTION.—Morphometric and meristic data for Crea- grutus ignotus in Table 25. Head and body relatively elongate across limited size range of available specimens. Greatest body depth at, or slightly anterior of, dorsal-fin origin. Dorsal profile of head distinctly convex anteriorly from margin of upper lip to vertical through posterior nostril, slightly convex from that point to tip of supraoccipital spine in smaller individuals, straight in that region in largest available specimens. Interor- bital region nearly flat transversely, noticeably more so in larger specimens. Predorsal profile of body slightly convex, some larger specimens showing barely apparent change in alignment of predorsal profile relative to that of head. Predorsal surface of body slightly flattened transversely proximate to tip of supraoccipital spine, with obtuse median ridge posteriorly proximate to dorsal-fin origin. Ventral profile of head gently curved from margin of lower lip to isthmus in smaller available specimens; with increasingly obvious obtuse angle at an- teroventral corner of dentary with increasing body size, and straight from that point to isthmus in larger specimens. Prepel- vic profile of body nearly straight, or gently convex, in all specimens. Prepelvic region obtusely flattened transversely in larger specimens. Head obtusely pointed in lateral view and more compressed laterally in dorsal view. Upper jaw distinctly longer than, and overhanging, lower jaw. Snout slightly fleshy, with scattered papillae anteromedially. Papillae more concentrated along ven- tral margin of lip and on fleshy folds and plicae extending be- tween outer and medial premaxillary teeth. Lower lip fleshy anteriorly, with numerous papillae along dorsal margin. Infraorbital series moderately developed. Ventral margin of third infraorbital falling short of horizontal limb of preopercle in smallest specimens, contacting that ossification in larger in- dividuals. Posterior margins of third through fifth infraorbitals falling distinctly short of vertical limb of preopercle in speci- mens of all sizes. Premaxillary dentition in three series: primary row slightly curved, typically consisting of 6 teeth (one paratype with only 5 teeth in primary row of each premaxillary), without distinct gap between first and second tooth of that series, but with me- dial tooth separated from anterior tooth of contralateral series by distinct gap; triangular cluster of 3 large teeth; and single tooth of form similar to that of primary series occurring lateral to fourth tooth of primary premaxillary tooth row. Maxilla with 2 or 3 tricuspidate teeth. Dentary with 6 teeth; anterior three teeth tricuspidate, fourth through sixth conical (in a 28.1 mm SL cleared and counterstained specimen); first and second den- tary teeth distinctly largest, with second tooth slightly larger than first and slightly more than two times height of third; fourth through sixth teeth compressed and distinctly smaller than third tooth. Dorsal-fin rays ii,8. Dorsal-fin origin approximately at verti- cal through pelvic-fin insertion. Profile of distal margin of dor- sal fin slightly concave. Anal-fin rays ii,9-ll. Profile of distal margin of anal fin concave, with last unbranched and 2 anteri- ormost branched rays forming anterior lobe. Hooks typically present on anal-fin rays in mature males of many Creagrutus species not present in limited available population samples. Pectoral-fin rays i,10-12. Tip of pectoral fin extending posteri- orly to point approximately 2 scales before pelvic-fin insertion. Pelvic-fin rays i,6,i. Hooks typically present on pelvic-fin rays in mature males of many Creagrutus species not present in lim- 124 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY FIGURE 48.—Creagrutus ignotus, new species, holotype, MZUSP 45310, 41.1 mm SL; Brazil, Mato Grosso, Riacho (small stream) 1, tributary to Rio Preto at road to San Francisco, Municipio de Diamantino (Rio Arinos basin). ited number of available specimens. Tip of pelvic fin extending posteriorly nearly to anal-fin origin. Gill rakers 6-8 + 9-11. COLORATION IN ALCOHOL.—Overall ground coloration ranging from yellow to tan in available specimens, all collected within last six years. Dorsal surface of head with numerous scattered, stellate, dark chromatophores. Chromatophore field either uniformly intense or with chromatophore concentration in field reduced over posterior fontanelle. Deeper-lying dark chromatophores covering membranes of brain. Chromatophore field on dorsal surface of head continuing anteriorly onto snout and upper lip. Chromatophores in this region more concen- trated anterior, anterodorsal, and anteroventral to anterior nos- tril and forming nearly semicircular arch. Arch continuous pos- teroventrally, with series of dark chromatophores anteroventral to orbit continuing to varying degrees around ventral and pos- terior margins of orbit. Relatively dense pattern of stellate chromatophores covering most of opercle and dorsal portions of infraorbital series. Scales of dorsolateral portion of body with exposed portions covered with stellate chromatophores. Chromatophore field more concentrated basally on each scale, giving somewhat re- ticulate pattern to that portion of body. Humeral mark variably vertically elongate, with somewhat irregular margins. Darker main portion of mark typically centered slightly above lateral line. Dorsal portion of mark formed of less concentrated field of chromatophores arranged in anteriorly arching pattern. Mid- lateral body stripe extending from suprapreopercle to rear of caudal peduncle, with humeral mark included within stripe an- teriorly. Stripe very diffuse anteriorly, particularly in smaller specimens, and becoming increasingly prominent posteriorly. Dorsal fin with dark pigmentation along margins of most fin- rays and large chromatophores scattered on distal one-half of anterior two-thirds of rays, chromatophore field most concen- trated in center of that region. Anal-fin rays variably outlined with dark pigmentation and with scattered chromatophores on distal one-half to two-thirds of membranes of anterior branched rays in some individuals. Caudal-fin rays variably outlined by dark chromatophores. Dark pigmentation most intense on three portions of caudal fin; middle rays and dorsalmost and ventral- most rays; these more pigmented regions separated by hyaline or less pigmented areas on middle rays of each caudal-fin lobe. Dark pigmentation of middle caudal-fin rays most intense ba- sally, forming very distinct spot in some larger specimens. Pec- toral and pelvic fins hyaline. ETYMOLOGY.—The specific name, ignotus, from the Latin for unknown, refers to the previous absence of any records for Creagrutus from the upper portions of the Rio Tapajos basin. ECOLOGY.—Stomach contents of a single examined speci- men of Creagrutus ignotus prepared for clearing and staining in this study consisted solely of parts of larval insects. DISTRIBUTION.—Creagrutus ignotus is known only from the upper portions of the Rio Tapajos basin, central Brazil (Figure 43, open stars). COMPARISONS.—Creagrutus ignotus is the only member of Creagrutus known from the upper portions of the Rio Tapajos system and one of only two Creagrutus species known from that drainage basin. Creagrutus ignotus is readily discriminated from C. cracentis, the second species known from the Rio Tapajos basin, in numerous features, most notably the arrange- ment of premaxillary dentition and numbers of teeth in the up- per jaw (see "Key to the Species of Creagrutus in the Amazon Basin"). MATERIAL EXAMINED.—23 specimens (23,26.8-53.0). HOLOTYPE.—BRAZIL. Mato Grosso: Riacho (small stream) 1, tributary to Rio Preto at road to San Francisco, Municipio de Diamantino (Rio Arinos basin), collected by N.A. Menezes et al., 24 Oct 1992, MZUSP 45310, 1 (41.1). PARATYPES.—14 specimens (14,26.8-41.8). BRAZIL. Mato Grosso: Riacho (small stream) 1, tributary to Rio Preto at road to San Francisco, Municipio de Diamantino (Rio Arinos basin), collected with holotype, MZUSP 50165, 2 (32.9-34.1); USNM 340960, 3 (32.6-41.8). Riacho (small stream) 3, tributary to Rio Preto at road to San Francisco, Mu- nicipio de Diamantino (Rio Arinos basin), collected by N.A. Menezes et al., 24 Oct 1992, MZUSP 45349, 3 (27.7-32.9); USNM 326672, 3 (26.8-30.5; 1 specimen cleared and counter- stained for cartilage and bone). Rio Juina, 31 km along road be- NUMBER 613 125 tween Juina and Fontanilhas, collected by S.O. Kullander et al., 13 Oct 1989, MZUSP 42456, 3 (32.7-41.0). NONTYPE SPECIMENS.—8 specimens (8, 31.7-53.0). BRAZIL. Mato Grosso: Creek crossing on highway BR-163, 54 km from Sinop, Mato Grosso in direction of Santarem, Para, tributary of Rio Teles-Pirez, upper Rio Tapajos system, USNM 353153,4 (33.2-53.0); MZUSP 53244, 4 (31.7-43.0). Creagrutus kunturus Vari, Harold, and Ortega, 1995 FIGURES 49-51, TABLE 26 Creagrutus mulleri [not of Giinther, 1859].—Bohlke, 1958:30 [misidentifica- tion] [specimens from Ecuador (Pastaza), Rio Arajuno]. Creagrutus kunturus Vari et al., 1995:290, figs. 1, 2 [type locality: Peru, Ama- zonas, Provincia Condorcanqui, Cordillera del Condor, upper Rio Comainas, 20 km upriver of Puesto de Vigilancia no. 22, 3°56'30"S, 78°24'20"W; com- parisons with C. amoenus].—Roman-Valencia and Cala, 1996:147 [similari- ty to C. amoenus. based on Van et al., 1995]. DIAGNOSIS.—The combination of the possession of premax- illary dentition arranged in the three components generalized for most of the species of Creagrutus and Piabina without a distinctly larger gap between the first and second teeth of the primary series, 2 or 3 teeth on the maxilla, 6, rarely 5, teeth in the primary tooth row of the premaxilla, 5 or 6 dentary teeth, 39 to 43 lateral line scales without a lamellar process over each pore, 12 predorsal median scales, 38 to 41 vertebrae, 11 to 13 branched anal-fin rays, 1 post-anal median scale to the anal-fin origin, 9 to 11 gill rakers on the lower limb of the first gill arch, the absence of a discrete secondary component dorsal to the main body of the humeral mark, the possession of a series of dark spots along the midlateral surface of the body that ontoge- netically coalesce in variable patterns, sometimes resulting in a solid dark stripe in larger individuals, and the absence of a dis- crete patch of dark pigmentation on the middle portion of the anterior dorsal-fin rays distinguishes Creagrutus kunturus from all species within the clade composed of Creagrutus and Piab- ina with the exception of C. amoenus. Creagrutus kunturus can be separated from C. amoenus by the combination of the num- ber of lateral line scales (39-43, rarely 39, in C. kunturus ver- sus 35-39, rarely 39, in C. amoenus), total vertebrae ( 3 8 ^ 1 , typically 39 or 40, in C. kunturus versus 36- 39, rarely 39, in C. amoenus), the depth of the caudal peduncle (11.1%-12.1% of SL in C. kunturus versus 12.2%-13.8% of SL in C. amoe- nus), and the distance from the dorsal-fin origin to the anal-fin origin (30.8%-34.0% of SL in C. kunturus versus 33.8%- 38.8% of SL in C. amoenus). DESCRIPTION.—Morphometric and meristic data for Crea- grutus kunturus in Table 26. Head and anterior portion of body relatively robust; region of body posterior of vertical through anal-fin origin more slender. Greatest body depth at, or slightly anterior of, vertical through dorsal-fin origin. Dorsal profile of head from tip of snout to rear of supraoccipital spine smoothly convex, some specimens with profile disrupted by irregular processes in region above nares. Interorbital region distinctly convex transversely. Predorsal profile of body slightly convex. TABLE 26.—Morphometrics and meristics of Creagrutus kunturus: (A) holo- type of C. kunturus. MUSM 5667; and (B) all specimens of C. kunturus from which counts and measurements were taken (n=31). Standard length is ex- pressed in mm; measurements 1 to 14=percentages of standard length; 15 to 18=percentages of head length. Characters Standard length 1. Snout to anal-fin origin 2. Snout to pelvic-fin insertion 3. Snout to pectoral-fin insertion 4. Snout to dorsal-fin origin 5. Dorsal-fin origin to hypural joint 6. Dorsal-fin origin to anal-fin origin 7. Dorsal-fin origin to pelvic-fin insertion 8. Dorsal-fin origin to pectoral-fin insertion 9. Caudal peduncle depth 10. Pectoral-fin length 11. Pelvic-fin length 12. Dorsal-fin length 13. Anal-fin length 14. Head length 15. Postorbital head length 16. Snout length 17. Bony orbital diameter 18. Interorbital width Lateral line scales Scale rows between dorsal-fin origin and lateral line Scale rows between anal-fin origin and lateral line Predorsal median scales Branched dorsal-fin rays Branched anal-fin rays Branched pelvic-fin rays Pectoral-fin rays Vertebrae A B Morphometrics 84.1 64.8 46.6 24.6 47.3 56.2 33.5 28.7 33.0 11.4 20.9 15.3 20.7 15.8 25.1 44.3 28.1 28.1 28.1 53.2-96.0 61.4-65.3 44.2-49.1 22.3-28.0 45.5-50.5 53.9-60.3 30.8-34.0 27.9-31.6 32.2-35.1 11.1-12.1 18.6-21.9 14.7-17.2 20.1-24.8 15.4-19.0 24.2-29.1 40.9-47.1 27.3-32.3 26.7-32.5 24.9-31.2 Meristics 41 5 4 12 8 12 7 13 39 39-43 4-5 3-4 12 7-8 11-13 6-7 12-14 38^1 with variably evident inflection of profile of head at rear of su- praoccipital spine (compare Figures 49 and 50). Ventral profile of head in many individuals with obtuse angle at anteroventral corner of dentary, gently curved from that region to isthmus. Ventral profile of body convex to anal-fin origin and slightly concave from anal-fin insertion to caudal fin. Head obtusely pointed in lateral view and distinctly pointed in dorsal view. Upper jaw distinctly longer than, and overhang- ing, lower jaw. Anterior portion of snout fleshy, with scattered papillae. Papilla more concentrated along ventral margin of up- per lip and on fleshy folds and plicae extending between outer and medial premaxillary teeth. Lower lip fleshy anteriorly with papillae along dorsal margin. Infraorbital series moderately developed. Central portion of ventral margin of third infraorbital contacting horizontal limb of preopercle. Posterior margins of third through fifth infraor- bitals distinctly separated from vertical limb of preopercle, gap decreasing gradually dorsally. Premaxillary dentition in three series: primary row slightly curved, typically with 6 teeth, 5 teeth present on both premaxil- 126 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY lae in one specimen and 7 teeth on one premaxilla in one speci- men, without pronounced gap between first and second tooth of series but with anteromedial tooth separated from contralateral equivalent by distinct gap filled by fleshy fold; triangular clus- ter of 3 larger teeth lying medial to primary row; and single tooth of form similar to that of primary series occurring lateral to fourth tooth of primary premaxillary row. Maxilla with 2 or 3 tricuspidate teeth. Dentary with 5 or 6 tricuspidate teeth; first and second dentary teeth distinctly larger than remaining teeth and subequal, approximately 1.7 times height of third tooth; fourth through fifth or sixth teeth distinctly smaller and com- pressed. Dorsal-fin rays typically ii,8, rarely iii,8 or ii,7. Dorsal-fin origin ranging from anterior of, to posterior to, vertical through pelvic-fin insertion. Profile of distal margin of dorsal fin straight to very slightly concave. Anal-fin rays i i , l l -13 or iii,11-13. Profile of distal margin of anal fin straight. Hooks typically present on anal-fin rays in mature males of many Cre- agrutus species not found in examined specimens. Pectoral-fin rays i,l 1-13. Relative length of pectoral fin somewhat variable, ranging from falling slightly short of vertical through pelvic-fin insertion to extending to beyond that line. Pelvic-fin rays i,6,i or i,7 with higher number of branched rays typical of larger in- dividuals. Tip of pelvic fin extending posteriorly to, or falling slightly short of, anus. Hooks typically present on pelvic-fin rays in mature males of many Creagrutus species not found in examined specimens. Gill rakers 7-8+ 9-11. COLORATION IN ALCOHOL.—Overall ground coloration of relatively freshly collected specimens light tan. Dorsal surface of head with dense field of small dark chromatophores, giving the region distinctly dusky appearance. Intensity of dark pig- mentation more noticeable over brain, presumably as conse- quence of deep-lying pigmentation overlying membranes of that organ in most Creagrutus species. Dense surface pigmen- tation continuing anteriorly over snout and upper lip. Crescent- shaped patch of denser pigmentation anterior to nares obvious in smaller specimens; not distinct from remaining dark pig- mentation anterior to orbit in larger individuals. Regions imme- diately ventral and posterior to orbit with pigmentation field in- terrupted by unpigmented laterosensory canal segments. Lower portion of cheek lacking dark chromatophores in all but largest individuals, which have scattered chromatophores in that re- gion. Variably developed pattern of dark pigmentation poste- rior to orbit; pigmentation ranging in form from diffuse, irregu- lar band, through overall diffuse band, to vertically elongate spot overlying portion of preopercle and margins of fourth and fifth infraorbitals, to distinct band with irregular dorsal and ventral borders extending from rear margin of orbit to rear mar- gin of opercle. Scales of dorsal portion of body with small dark chromato- phores concentrated along posterior scale margin, forming overall reticulate pattern. Humeral mark vertically elongate, with most intensely pigmented region centered immediately dorsal of lateral line. Small ventrally attenuating, less densely pigmented region extending ventrally from main body of hu- meral mark as far as one scale row ventral of lateral line. Dis- tinct, anteriorly concave, more diffuse area of dark pigmenta- tion extending approximately two scale rows anterodorsally from dorsal margin of region of darkest pigmentation. Midlat- eral body pigmentation highly variable both ontogenetically and between comparably sized individuals, formed of two components: band of dark deep-lying chromatophores and overlying patches of dark surface pigmentation. Surface pig- mentation ranging from discrete, widely separated spots of ap- proximately size of pupil of eye, through variously coalesced spots, to nearly continuous dark band extending from near pos- terior margin of humeral mark posteriorly to base of middle caudal-fin rays. Dorsal fin with membranes and margins of fin rays with small dark chromatophores, particularly on distal two-thirds of fin; intensity of pigmentation increasing ontogenetically. Basal portions of anal-fin rays outlined by small dark chromato- phores in medium-sized individuals, rays nearly completely outlined in larger specimens. Caudal fin with rays and mem- branes with associated small dark chromatophores, particularly in larger individuals. Distinct band of dark pigmentation on middle caudal-fin rays; band most intense basally. Pelvic and pectoral fins nearly hyaline in smaller individuals, dusky in larger specimens. ECOLOGY.—The collecting localities of the holotype and paratype series are at an altitude of 850-900 m, along the Cor- dillera del Condor. In that region the Rio Comainas is shallow with clear water for most of the year, but it becomes torrential with white waters during, and after, heavy rains. The river var- ies from 8 to 20 m in width, with the main channel during low water periods being 30 to 190 cm deep over a bottom of rocks, pebbles, sand, and clay. The nontype specimens collected at Chigkan entse (=Quebrada Chigkan) (LACM 39681-1) also came from a relatively shallow stream approximately 4 m wide with moderate current. The single specimen cleared and coun- terstained, which was collected during late July, had very well- developed testes and had fed on larval and adult insects. DISTRIBUTION.—Creagrutus kunturus is distributed through the upper Rio Maranon in northeastern Peru and through the upper Rio Pastaza to the southwestern portion of Rio Napo in southeastern Ecuador (Figure 51, dots). COMPARISONS.—Creagrutus amoenus, a species very simi- lar to C. kunturus (see "Diagnosis," above), also occurs in the Rio Pastaza and Rio Napo basins, but the two species are not known to be syntopic. In both the Rio Pastaza and Rio Napo basins and throughout its range, C. amoenus occurs in regions of somewhat lower altitude than does C. kunturus (compare Figures 22 and 51). REMARKS.—Bohlke (1958:30) identified a series of speci- mens from eastern Ecuador as Creagrutus miilleri and these were, in turn, considered to be C. boehlkei by Gery (1972:63) in his original description of the latter species. The series re- NUMBER 613 127 FIGURE 49.—Creagrutus kunturus. holotype, MUSM 5667, 84.1 mm SL; Peru, Amazonas, Condorcanqui, Cor- dillera del Condor, upper Rio Comainas, 20 m upriver of Puesto de Vigilancia No. 22 (3°56'30"S, 78°24'20"W). FIGURE 50.—Creagrutus kunturus, KU 19977, 82.5 mm SL; Ecuador, Pastaza, Rio Alpayacu, 1 km E of Mera (1°28'S, 78°07'W). ported on by Bohlke has proven to be complex, consisting mostly of C. amoenus (the senior synonym of C. boehlkei), but with two lots (USNM 164066 and presumably ANSP 75911, which was removed from it) being specimens of C. kunturus. MATERIAL EXAMINED.—43 specimens (31, 53.2-96.0). PERU. Amazonas: Provincia Condorcanqui, Cordillera del Condor, upper Rio Comainas, 20 m upriver of Puesto de Vigi- lancia No. 22 (3°56'30"S, 78°24'20"W), MUSM 5667, 1 (84.1, holotype of Creagrutus kunturus); MUSM 6593, 1 (77.5, paratype of Creagrutus kunturus); USNM 335146, 1 (82.3, paratype of Creagrutus kunturus). Provincia Condorcanqui, Cordillera del Condor, Quebrada no. 1, tributary of Rio Co- mainas, PV 22, MUSM 5669, 3 (62.2-64.5). Provincia Con- dorcanqui, Cordillera del Condor, Rio Comainas, 30 m down river of Puesto de Vigilancia No. 22 (3°56'30"S, 78°24'20"W), MUSM 5665, 2 (57.3-58.0, paratypes of Creagrutus kunturus); USNM 335148, 2 (63.8-65.3, paratypes of Creagrutus kuntu- rus). Provincia Condorcanqui, Cordillera del Condor, Rio Co- mainas, 40 m upriver of Puesto de Vigilancia No. 22 (3°56'30"S, 78°24'20"W), MUSM 5663, 1 (90.3, paratype of Creagrutus kunturus). Provincia Condorcanqui, Cordillera del Condor, Quebrada no. 3, tributary of Rio Comainas, Puesto de Vigilancia No. 22 (3o56'30"S, 78°24'20"W), MUSM 5668, 2 (64.2-75.6, paratypes of Creagrutus kunturus); USNM 335147, 2 (64.3-68.6, paratypes of Creagrutus kunturus; 1 specimen cleared and counterstained for cartilage and bone). Rio Cenepa, Chigkan entse (=Quebrada Chigkan) tributary to Rio Cenepa (4°28'S, 78°10'W), LACM 39681-1, 3 (72.0- 92.0). Rio Alto Comainas, vicinity of Shaim (04°15'S, 78°22'W), LACM 39686-15, 1. ECUADOR. Pastaza; Rio Alpayacu, 1 km E of Mera (1°28'S, 78°07'W); KU 19977, 3 (65.5-82.5). Upper portion of Rio Arajuno, few km NE of El Puyo, Rio Napo basin (approxi- mately 1°24-26'S, 77°50-55'W), USNM 164066, 2 (75.2- 128 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY -2 4 FIGURE 51.—Map of central and northern South America showing geographic distribution of Creagrutus kuntu- rus (dots, 1 =type locality), Creagrutus lassoi (square, 2=type locality, same area as type locality of C. lepidus), Creagrutus lepidus (square, 2=type locality, same area as type locality of C. lassoi), Creagrutus machadoi (star, 3=type locality), Creagrutus magoi (triangles, 4=type locality), and Creagrutus manu (diamond, 5=type local- ity) (some symbols represent more than one locality or lot of specimens). 96.0); ANSP 75911, 1. Rio Pundo Grande, Puyo, MEPN 9838, 1. Rio Conambo, at the settlement of Moretecocha (0°36'S, 77°24'W), MEPN 4635, 11 (8, 53.2-71.4); USNM 340956, 6. Creagrutus lassoi, new species FIGURES 51, 52, TABLE 27 Creagrutus beni [not of Eigenmann, 1911].—Fernandez-Yepez, 1972, pi. 14: fig. 1 [misidentification] [Rio Yaracuy].—Gery and Renno, 1989:5 [identifi- cation of population identified as C. beni by Fernandez-Yepez, 1972, ques- tioned]. DIAGNOSIS.—The combination of the possession of premax- illary dentition arranged in the three components generalized for most of the species of Creagrutus and Piabina without a distinctly larger gap between the first and second teeth of the primary series, 2 to 5 teeth on the maxilla, 6 teeth in the pri- mary tooth row of the premaxilla, 4 dentary teeth, 36 to 38 lat- eral line scales without a lamellar process over each pore, 9 to 11 predorsal median scales, 4 scale rows between the dorsal-fin origin and the lateral line, the lack of crenation on the scales of the posterior margin of many scales on the lateral surface of the body, 35 or 36 vertebrae, 10 to 12 branched anal-fin rays, 1 or 2 post-anal median scales to the anal-fin origin, the bony orbital diameter (23.3%-32.3% of HL), the postorbital length (46.7%~53.5% of HL), the poorly developed third infraorbital distinctly separated from the horizontal limb of the preopercle, the lack of a series of dark midlateral spots on the body, the hu- meral mark nearly vertical or slightly posterodorsally to antero- dorsally inclined, the presence of a narrow medial predorsal line of dark pigmentation, and the absence of a discrete patch of dark pigmentation on the middle portion of the anterior dor- NUMBER 613 129 sal-fin rays distinguishes Creagrutus lassoi within the clade composed of Creagrutus and Piabina. DESCRIPTION.—Morphometric and meristic data for Crea- grutus lassoi in Table 27. Body moderately deep and com- pressed. Greatest body depth ranging from slightly anterior of pelvic-fin insertion anteriorly as far as one-half of distance to pectoral-fin insertion. Large specimens much deeper and more compressed than smaller individuals. Dorsal profile of head distinctly convex from margin of upper lip to vertical between nares, straight from that point to rear of supraoccipital spine or with very slight concavity above eye. Dorsal profile of body slightly convex to dorsal-fin origin, inclination of predorsal re- gion greatest in large specimens and in some individuals accen- tuated by hump-like inflection point immediately posterior to supraoccipital spine. Dorsal profile typically straight from dor- sal-fin origin to caudal peduncle. Ventral profile of head with obtuse angle approximately midway between margin of lower lip and posterior of dentary, slightly to highly convex from that point approximately to pelvic-fin insertion; distinctly concave from anal-fin origin to caudal peduncle. Upper jaw longer than, and overhanging, lower jaw. Anterior portion of snout quite fleshy, with many minute papillae on an- teromedial portion of snout, papillae continuing ventrally onto upper lip and into mouth on fleshy flaps between premaxillary teeth. Continuous field of papillae covering most of head, evi- dently well developed in both sexes. Lower jaw distinctly fleshy anteriorly, with papillae most concentrated on lip and decreasing in number ventrolaterally, but extending postero- ventrally in large numbers to isthmus and posteriorly over scales of anterior portion of abdomen. Infraorbital series poorly developed, with ventral margin of third infraorbital rounded and roughly concentric with postero- ventral margin of orbit. Ventral and posterior margins of third infraorbital separated from horizontal and vertical limbs of pre- opercle by gaps equal in width to approximately one-fourth of orbital diameter; large posteroventral gap approximately equal in width to diameter of pupil separates third infraorbital from inflection of preopercle. Posterior margins of fourth and fifth infraorbitals separated from vertical limb of preopercle by broad gap equal in width to approximately one-half that of re- spective infraorbital; gap slightly decreasing in width dorsally. Premaxillary dentition in three series: primary row gently curved along line of premaxillary margin, without pronounced gap between first and second tooth of series, typically with 6 tricuspidate teeth, occasionally 5 teeth present on one premax- illa; anterior 4 teeth large and similarly developed, fifth and sixth teeth smaller with relatively reduced secondary cusps; triad of larger teeth with relatively prominent secondary cusps especially developed on posterior two teeth with posterolateral tooth largest; and single tooth of form similar to that of primary row lateral to fourth tooth of primary series. Maxilla with 2 to 5 tricuspidate teeth, 3 or 4 teeth most common. Dentary with 5 teeth, all tricuspidate except for conical last tooth in series; an- terior two teeth largest with second tooth somewhat higher and TABLE 27.—Morphometrics and meristics of Creagrutus lassoi. new species: (A) holotype of C. lassoi, INHS 60094; and (B) paratypes of C. lassoi from which measurements and counts were taken (n=18). Standard length is ex- pressed in mm; measurements 1 to I4=proportions of standard length; 15 to 18= proportions of head length. Characters Standard length 1. Snout to anal-fin origin 2. Snout to pelvic-fin origin 3. Snout to pectoral-fin origin 4. Snout to dorsal-fin origin 5. Dorsal-fin origin to hypural joint 6. Dorsal-fin origin to anal-fin origin 7. Dorsal-fin origin to pelvic-fin insertion 8. Dorsal-fin origin to pectoral-fin insertion 9. Caudal peduncle depth 10. Pectoral-fin length 11. Pelvic-fin length 12. Dorsal-fin length 13. Anal-fin length 14. Head length 15. Postorbital head length 16. Snout length 17. Bony orbital diameter 18. Interorbital width Lateral line scales Scale rows between dorsal-fin origin and lateral line Scale rows between anal-fin origin and lateral line Predorsal median scales Branched dorsal-fin rays Branched anal-fin rays Branched pelvic-fin rays Pectoral-fin rays Vertebrae A B Morphometrics 47.5 61.7 44.4 26.5 51.6 53.5 31.2 31.6 37.7 14.1 22.5 17.1 22.1 18.1 28.0 47.4 27.1 31.6 29.3 40.5-75.4 59.5-66.9 41.9-51.1 24.4-27.3 47.5-53.6 51.8-57.4 28.9-34.1 27.4-33.1 33.9-40.1 11.3-13.8 19.3-22.3 14.1-17.3 19.1-22.7 15.5-20.6 25.7-30.4 46.7-53.5 26.5-33.5 23.3-32.3 29.5-33.5 Meristics 37 4 3 11 8 11 7 12 36 36-38 4 3 9-11 7-8 10-12 7-8' 11-12 35-36 'Eight branched pelvic-fin rays present in only 1 specimen. distinctly wider than first tooth and more than twice as high as third tooth. Remaining dentary teeth becoming progressively smaller posteriorly. Dorsal-fin rays ii,7 or 8. Dorsal-fin origin located at, to slightly posterior of, vertical through pelvic-fin insertion. Dis- tal margin of dorsal fin slightly concave; elongation of anterior lobe barely noticeable. Anal-fin rays ii or iii,10-12. Anal fin in mature males with hooks on segments of anterior two to four branched rays; hooks, if present on fourth ray, usually poorly developed. Distal margin of anal fin sinusoidal, with slightly elongate anterior lobe approximately twice as long as posteri- ormost branched ray. Pectoral-fin rays i, 10 or 11. Tip of pecto- ral fin approaching or extending past pelvic-fin insertion. Pel- vic-fin rays i,7, rarely i,8 or i,6,i. All pelvic-fin rays branched, except medial ray in most examined specimens (unbranched in 13 of 19 specimens). Tip of pelvic fin extending posteriorly to anal-fin origin in mature males, in other specimens fin-tip usu- ally separated from anal-fin origin by distance equal to approx- 130 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY imately one scale. Pelvic fin in mature males with hooks on segmented and unsegmented portions of all branched rays and medial ray if unbranched, some specimens with hook on both lateral and medial surfaces of segments, especially on medial three rays. Posterior margin of body scales slightly undulate to crenate; scale striae clearly visible. Gill rakers 5-8+ 9-11. COLORATION IN LIFE.—(Observations based on specimens from the Rio Tupe, Estado de Yaracuy (MCNG 24685), fixed in formalin and stored in ethanol for three years but retaining some life colors). All unbranched and anterior two branched anal-fin rays, lateral unbranched and first branched pelvic-fin rays, and lateral pectoral-fin rays bright yellow. Both lobes of caudal fin bright yellow, pigmentation most intense in membranes associ- ated with outer 2 or 3 rays; distal one-half of ventral caudal-fin lobe orange. Unbranched dorsal-fin rays yellow but pigmenta- tion less intense than in other fins. Anterodorsal surface of eye orange-red, with overlying layer of reflective guanine. COLORATION IN ALCOHOL.—Dorsal surface of head with diffuse pattern of small dark chromatophores continuing anteri- orly onto snout and medial portions of upper jaw, with distinct small crescent of dark chromatophores immediately in front of anterior nares; pattern of chromatophores more irregular and diffuse laterally proximal to eye. Band of scattered, dark chro- matophores extending from snout onto dorsal surface of cheek and continuing around posterior margin of orbit; noticeable concentration of pigmentation anteroventral of eye. Lateral sur- face of head with scattered stellate chromatophores on dorsal one-half of cheek and covering area behind eye and upper one- half of opercle; remainder of head without pronounced pig- mentation pattern. Body with pigmentation most concentrated dorsally, particu- larly at dorsal-fin base and below center of exposed surface of scales in broad, vertical, anteriorly concave band; extreme pos- terior margins of scales outlined by fine, dark pigment. Mid- dorsal stripe, especially visible in mature males, consisting of concentrated dark chromatophores present below scales on an- terior one-half of middorsal region and between bases of dorsal and adipose fins. Humeral mark most highly pigmented imme- diately dorsal of lateral line, extending ventrally one scale row below lateral line and dorsally three rows; overall form of mark bar-like, ranging from vertical to somewhat posterodorsally to anteroventrally oblique. Bar somewhat diffuse in large speci- mens. Pigmentation on lateral surface of body, other than for that associated with humeral bar, restricted to area dorsal of lat- eral line except for weakly delineated myosepta dorsal of anal- fin base. Midlateral body stripe diffuse anteriorly, becoming more densely pigmented and somewhat wider posteriorly on caudal peduncle. Reflective guanine layer very well developed, especially in association with, and mostly masking, midlateral stripe. Caudal-fin rays all delineated by dark pigment, pigmentation darkest on ventral one-half of fin; membranes of ventral one- half of fin covered with diffuse dark chromatophores and ex- tending to distal margin. Unbranched anal-fin rays unpig- mented, branched rays delineated by small, dark chromato- phores, pigmentation especially developed basally where chromatophores slightly enlarged. Anterior portion of anal fin in some specimens with scattered, large, dark chromatophores on distal membranes. Dorsal-fin membrane and ray margins with many dark chromatophores, except near base and on last two branched rays where pigmentation poorly developed or ab- sent. Pectoral-fin rays delineated by dark chromatophores along their medial surfaces. Pelvic fin hyaline. ETYMOLOGY.—The specific name, lassoi, is in honor of Car- los A. Lasso of the Museo de Historia Natural La Salle, Cara- cas and the Asociacion Amigos de Donana, Seville, in recogni- tion of his many contributions to our knowledge of the fishes of Venezuela and his assistance to the authors. ECOLOGY.—Creagrutus lassoi is sympatric, and possibly syntopic, with C. lepidus in the Quebrada El Charal, Rio Aroa system. The general habitat for this low elevation water body was described by Vari et al. (1993) and is repeated under "Ecol- ogy" in the C. lepidus account herein. Fernandez-Yepez (1972) found C. lassoi (identified therein as C. beni) at three of the eleven collecting locations in the Rio Yaracuy drainage. These collections also may have included C. taphorni because both forms were at that time included in the rather broad conception of C. beni applied by previous authors. Fernandez-Yepez (1972, pi. 14) noted that C. lassoi (identified by that author as C. beni) inhabits clear waters and feeds on algae from sub- merged stones and logs. COMMON NAME.—Venezuela: "Pico de Loro" (Fernandez- Yepez, 1972, pi. 14). DISTRIBUTION.—Creagrutus lassoi occurs only in the Rio Aroa and Rio Yaracuy systems, Caribbean versant drainages of north central Venezuela (Figure 51, square). COMPARISONS.—Reflective guanine is highly developed on the lateral surfaces of the body in Creagrutus lassoi, a feature that distinguishes it from all other congeners in rivers of the Caribbean versant and through the Rio Orinoco basin. Crea- grutus lassoi occurs with C. lepidus in the Rio Aroa system of the Carribean slope. The two species are readily distinguish- able on the basis of pigmentation and overall body form (com- pare Figures 51 and 53). Creagrutus lassoi is distinguished from C. taphorni, a similar species from that region and with which it co-occurs in the Rio Yaracuy, by the undulate to crenate posterior margins of midlateral scales and by the occa- sional presence of a hook on both the medial and lateral surface pelvic-ray segments, features absent in C. taphorni. Creagrutus crenatus is most similar to C. lassoi, especially with regard to meristics and fin-ray hook morphology. These two species dif- fer in the straight posterior opercular margin in C. crenatus compared with the concave posterior opercular margin in C. lassoi, the modally higher number of branched anal-fin rays and lateral line scales in C. crenatus versus C. lassoi, and the crenate posterior scale margins, especially along the midlateral NUMBER 613 131 FIGURE 52.—Creagrutus lassoi, new species, holotype, INHS 60094, 47.5 mm SL; Venezuela, Yaracuy, Rio Tupe, Rio Aroa drainage, approximately 12 km N of Aroa, on Highway 3 (1O°3O'19"N, 68°52'33"W). surface of the body in C. crenatus in comparison to the typi- cally smooth scale margins in C. lassoi. GEOGRAPHIC VARIATION.—Three specimens from the Rio Mayorica, Rio Yaracuy drainage (INHS 34937) that represent the only documented occurrence of C. lassoi outside of the ad- jacent Rio Aroa drainage, have most of the diagnostic features of the species. The body in the Rio Mayorica sample is propor- tionally a little shallower and less compressed, giving the spec- imens a slightly more rotund appearance. In addition, hooks observed on the pelvic rays are confined to the medial surface of the fin, a feature also observed in many of the smaller ma- ture males from the Rio Aroa drainage. REMARKS.—Creagrutus lassoi is one of several forms that we recognize from Venezuela that were previously regarded as components of a wide ranging and variable C. beni by Eigen- mann (1927), Schultz (1944), and a series of other authors. A photograph of C. lassoi was published by Fernandez-Yepez (1972, pi. 14: fig. 1) who, however, clearly included this mate- rial from the Rio Yaracuy with other "C beni," which he con- sidered to occur across northern Venezuela from the Andean piedmont to the Rio Orinoco delta, although noting (text asso- ciated with pi. 14) that C. beni, in the sense that it was then uti- lized, might subsume other species. Gery and Renno (1989:5) noted that the material identified by Fernandez-Yepez (1972) as C. beni differed from specimens of the latter species from its type region in details of pigmentation and squamation. This "forme venezuelienne," as it was cited by Gery and Renno (1989), included, however, two Creagrutus species: C. taphorni (the Lago de Valencia populations cited by those au- thors) and C. lassoi (the Rio Yaracuy population of those au- thors). MATERIAL EXAMINED.—81 specimens (15,40.5-75.4). HOLOTYPE.—VENEZUELA. Yaracuy: Rio Tupe, Rio Aroa drainage, approximately 12 km N of Aroa, on Highway 3 (10°30'19"N, 68°52'33"W), collected by L.M. Page et al., 31 Dec 1990, INHS 60094 (47.5). PARATYPES.—77 specimens (14, 40.5-75.4). VENEZUELA. Yaracuy: Rio Tupe, Rio Aroa drainage, ap- proximately 12 km N of Aroa, on Highway 3 (10°30'19"N, 68°52'33"W), collected with holotype, INHS 51283, 22; USNM 359487, 5. Rio Tupe, N of town of Aroa, E of San Jose (1O°3O'31"N, 68°52'55"W), collected by D.C. Taphorn et al., 31 Dec 1990, MCNG 24685, 29 (10, 40.5-61.4). Cano Carip- ial, Rio Aroa drainage, 13 km SE of Yumare (10°33'42"N, 68°37'37"W), collected by D.C. Taphorn et al., 21 Jan 1995, INHS 34917, 2. Rio Crucito, Rio Aroa drainage, Guyamiro (10°29'08"N, 68°39'40"W), collected by D.C. Taphorn et al., 7 Jan 1993, INHS 28890, 1. Quebrada El Charal, Finca El Jag- uar, Sierra de Aroa (approximately 10°32'N, 68°32'W), col- lected by C. Lasso and J. Medina, MHNLS 4143, 18 (4, 47.5-75.4), 24 Jul 1985. NONTYPE SPECIMENS.—3 specimens. VENEZUELA. Yaracuy: Rio Mayorica, Rio Yaracuy basin, 9 km N of Alberico at Highway 3 (10°25'42"N, 68°40'47"W), INHS 34937, 3. Creagrutus lepidus Vari, Harold, Lasso, and Machado-Allison, 1993 FIGURES 51, 53, TABLE 28 Creagrutus lepidus Vari et al., 1993:351, fig. 1 [type locality: Venezuela, State of Yaracuy, Rio Aroa basin, Quebrada El Charal, Finca El Jaguar, Sierra de Aroa, approximately 1O°32'N, 68°32'W] —Evers 1996:7, color cover photo [northern Venezuela; see "Remarks," below, concerning exact locality].—Jo- hannes, 1996:13 [Venezuela, Carabobo, Rio Urama].—Taphom et al., 1997: 71 [cited for Venezuela],—Lasso et al., 1997:41 [type specimen listing], DIAGNOSIS.—Creagrutus lepidus can be distinguished readily from all congeners and Piabina by the autapomorphic presence of a very dark midlateral stripe extending posteriorly from the pectoral girdle to the baseof the central caudal-fin rays in specimens of all sizes. This stripe apparently subsumes the dark humeral mark typical of Creagrutus species, with the hu- meral mark consequently not apparent across the size range of examined specimens. The species also is unique within the 132 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY TABLE 28.—Morphometrics and meristics of Creagrutus lepidus: (A) holotype of C. lepidus, MHNLS 9659; and (B) all specimens of C. lepidus from which counts and measurements were taken (n=46). Standard length is expressed in mm; measurements 1 to 14=percentages of standard length; 15 to 18=percent- ages of head length. Characters Standard length 1. Snout to anal-fin origin 2. Snout to pelvic-fin insertion 3. Snout to pectoral-fin insertion 4. Snout to dorsal-fin origin 5. Dorsal-fin origin to hypural joint 6. Dorsal-fin origin to anal-fin origin 7. Dorsal-fin origin to pelvic-fin insertion 8. Dorsal-fin origin to pectoral-fin insertion 9. Caudal peduncle depth 10. Pectoral-fin length 11. Pelvic-fin length 12. Dorsal-fin length 13. Anal-fin length 14. Head length 15. Postorbital head length 16. Snout length 17. Bony orbital diameter 18. Interorbital width Lateral line scales Scale rows between dorsal-fin origin and lateral line Scale rows between anal-fin origin and lateral line Predorsal median scales Branched dorsal-fin rays Branched anal-fin rays Branched pelvic-fin rays Pectoral-fin rays Vertebrae A B Morphometrics 37.9 61.7 46.4 26.1 50.7 56.5 33.8 32.7 35.8 12.7 21.1 19.5 29.8 23.7 26.4 48.0 32.0 32.0 30.0 24.5-47.1 60.6-64.8 45.8^*9.2 26.0-28.3 47.6-52.4 54.6-57.3 32.4-36.1 31.3-35.6 35.8-37.6 10.8-13.7 20.1-23.0 17.8-20.3 26.4-31.2 22.1-25.5 25.5-27.7 44.4-48.5 27.1-31.9 30.9-35.8 27.8-31.9 Meristics 36 6 4 11 8 11 7 12 35 36-37 5-6 4-5 10-12 8 11-13 7 10-13 34-35 Creagrutus-Piabina lineage in having a reduced fifth infraor- bital situated completely ventral of the sixth infraorbital. In ad- dition, the combination of the possession of premaxillary denti- tion arranged in the three components generalized for most of the species of Creagrutus and Piabina without a distinctly larger gap between the first and second teeth of the primary se- ries, 3 or 4 teeth on the maxilla, 5 teeth in the primary tooth row of the premaxilla, 6 dentary teeth, 36 or 37 lateral line scales without a lamellar process over each pore, 10 to 12 pre- dorsal median scales, 5 or 6 scale rows between the dorsal-fin origin and the lateral line, 34 or 35 vertebrae, 11 to 13 branched anal-fin rays, the poorly developed third infraorbital distinctly separated ventrally from the horizontal limb of the preopercle, the presence of a distinct midlateral stripe along the entire length of the body, the absence of a distinct humeral mark, which is apparently subsumed into the midlateral stripe, and the absence of a discrete patch of dark pigmentation on the middle portion of the anterior dorsal-fin rays distinguishes Cre- agrutus lepidus within the clade composed of Creagrutus and Piabina. DESCRIPTION.—Morphometric and meristic data for Crea- grutus lepidus in Table 28. Body moderately deep compared with most congeners. Greatest body depth approximately at vertical through pelvic-fin insertion. Anterior profile of snout and dorsal profile of head meeting in rounded obtuse angle near vertical line immediately anterior of nares. Dorsal profile of head posterior of that line straight and distinctly posterodor- sally inclined. Predorsal profile of body with notable change in alignment relative to that of head; asymmetrically convex, with convexity most pronounced in anterior one-fourth of that re- gion. Dorsal profile of body nearly straight from dorsal-fin ori- gin to caudal peduncle. Ventral profile of head and body smoothly convex from margin of lower lip to pelvic-fin inser- tion; rounded obtuse angle on ventral surface of lower jaw at anteroventral corner of dentary typical of many Creagrutus species not apparent. Upper jaw distinctly longer than, and overhanging, lower jaw. Anterior portion of snout fleshy, with minute papillae dis- tributed over anterior of snout and continuing onto upper lip, margin of upper jaw, and into mouth on fleshy folds between inner and outer rows of premaxillary teeth. Lower lip distinctly fleshy, particularly anteriorly, with papillae most numerous on dorsal surface of lip and continuing in decreasing numbers pos- teroventrally. Infraorbital series weakly developed, covering approxi- mately one-half of cheek. Ventral margin of third infraorbital distinctly separated from horizontal limb of preopercle. Poste- rior margins of third through fifth infraorbitals well separated from vertical limb of preopercle. Posteroventral margin of in- fraorbital series rounded and nearly concentric with postero- ventral margin of orbit. Premaxillary dentition in three series: primary row with 5 rounded, unicuspidate to tricuspidate teeth with second through fifth teeth in straight row, and first tooth displaced somewhat medially relative to rest of series, but without distinct gap be- tween first and second teeth of series accommodating anterior tooth of triad of large teeth; triangular cluster of 3 larger teeth with more prominent cusps located medial to primary row; and single tooth similar in morphology to those of primary row, oc- curring lateral to third or fourth tooth of that series. Maxilla with 3 or 4 conical to tricuspidate teeth. Dentary with 6 teeth; 4 anterior teeth large and tricuspidate, followed by 2 small coni- cal teeth. Dorsal, anal, and pelvic fins relatively elongate compared with those of other Creagrutus species. Dorsal-fin rays ii,8 or iii,8; when 3 unbranched rays present, first sometimes well de- veloped (e.g., Figure 53). Dorsal-fin origin slightly posterior of vertical through pelvic-fin insertion. Profile of distal margin of dorsal fin nearly straight, but with anterior rays slightly elon- gate. Anal-fin rays ii, 11-13 or iii, 11-13. Mature males with hooks on anterior 9 or 10 branched anal-fin rays; hooks proxi- mally directed, with one hook per segment on posterior branched and segmented portion of main shaft of rays. Pecto- ral-fin rays i, 10-13. Tip of pectoral fin extending posteriorly NUMBER 613 133 FIGURE 53.—Creagrutus lepidus, holotype, MHNLS 9659, 37.9 mm SL; Venezuela, Estado Yaracuy, Rio Aroa basin, Quebrada El Charal, Finca El Jaguar, Sierra de Aroa (approximately 10°32'N, 68°32'W). to, or slightly beyond, pelvic-fin insertion. Pelvic-fin rays i,7. Tip of pelvic fin usually extending posteriorly to beyond anal- fin origin; with distal portion turned medially, giving fin slightly cup-shaped appearance. Branched rays of pelvic fin in mature males with hooks present on all portions of fin rays with exception of smaller distal branches. Gill rakers 6-7+ 9-10. COLORATION IN LIFE (based on photographs of live aquar- ium specimens provided by H.G. Evers).—Overall coloration darker on dorsal portions of head and body. Dorsal portion of iris golden. Head and body flecked with golden spots. Golden coloration concentrated into patches on opercle and on ventro- lateral portion of body above anal-fin base. Dark midlateral stripe obvious, continuing onto middle caudal-fin rays. Lateral ray of pelvic fin and distal portions of anterior rays of dorsal and anal fins white. COLORATION IN ALCOHOL.—Head of specimens from the type locality in the Rio Aroa basin with pattern of diffuse, dark chromatophores on dorsal surface, chromatophores most con- centrated posteriorly and on snout and upper lip, with small crescent of dark pigmentation immediately anterior of nares; crescent particularly obvious in some overall darker specimens from Rio Urama. Some specimens from the Rio Urama with overall head pigmentation significantly darker than samples from the Rio Aroa system, with chromatophores larger and more concentrated. Band of scattered, dark chromatophores ex- tending from pigmentation on snout posteriorly to anteroven- tral margin of orbit, continuing around ventral and posterior margins of orbit; band developed to differing degrees along its length and between specimens. Lateral surface of head with nu- merous scattered, dark chromatophores overlying posterodor- sal portions of infraorbital series and dorsal, and sometimes middle, regions of opercle. Pigmentation on middle region of opercle limited to scattered chromatophores other than in sub- set of specimens from Rio Urama in which pigmentation more concentrated. Those specimens also have dark chromatophores on dorsal portion of opercle forming solid dark mark. Dorsal portion of body with dark pigmentation concentrated on posterior exposed portion of scales, but with posterior mar- gin of each scale unpigmented; overall pigmentation pattern re- ticulate. Reticulate pattern nearly completely masked by darker overall body pigmentation in some individuals from Rio Urama basin. Distinct midlateral dark stripe extending posteri- orly from pectoral girdle to slightly beyond bases of central caudal-fin rays. Stripe generally most sharply defined ven- trally, extending below lateral line in region posterior of verti- cal through anal-fin origin, gradually merging dorsally into dark pigmentation on body, more so anteriorly. Limits of ante- rior portion of midlateral stripe somewhat variable, but always extending ventral of lateral line, perhaps representing imbed- ded humeral mark of many Creagrutus species. Stripe not quite as distinct in Rio Urama sample, perhaps as a result of speci- mens having been kept as aquarium specimens. Two Rio Urama specimens with stripe fainter than in Rio Aroa samples, fading anteriorly. Other two Rio Urama specimens with ante- rior and to a degree dorsal portions of stripe merging into over- all dark body pigmentation. Central caudal-fin rays with large dark chromatophores ba- sally. Diffuse dark smaller chromatophores associated with re- mainder of central rays and extending across distal portion of ventral lobe of fin. Dark chromatophores also associated with five dorsalmost branched rays of upper lobe of caudal fin. Pos- terior dorsal and ventral procurrent rays darkly pigmented. Anal fin with dark pigmentation associated with anterior sur- face of basal portions of rays. Rio Aroa population samples with scattered, darker, small chromatophores on distal portions 134 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY of fin membranes; pigmentation on this portion of anal-fin rays more pronounced in limited sample from the Rio Urama, par- ticularly in two specimens with distinctly darker overall pig- mentation. Pectoral-fin rays outlined by small dark chromato- phores. Pelvic fins hyaline in nearly all specimens, with scattered chromatophores in darker specimens from Rio Urama. ECOLOGY.—The type locality of Creagrutus lepidus is a rel- atively small stream with alternating pools (to 3 m depth) and regions of rapid current. The bottom is mostly sandy with nu- merous larger stones and lacks submerged vegetation. Crea- grutus lepidus in more abundant in pools than in regions of rapid current flow, gathering in groups of 15 to 30 individuals typically distributed from the middle to the bottom of the water column (C.A. Lasso, pers. comm., 1992). Johannes (1996: 13-14) reported that in the Quebrada Aqua Clara, a tributary to the Rio Urama, the species' habitat was a 50 cm deep stream with pools 2 m deep. The pH of the water at that locality was 8.0. Two specimens prepared for clearing and staining in this study and examined for gut contents, had only chopped seeds in their stomach and intestines. DISTRIBUTION.—Creagrutus lepidus is only known from the Rio Aroa and Rio Urama, Caribbean Sea versant drainages of northern Venezuela (Figure 51, square; see also "Remarks," be- low). COMPARISONS.—In addition to Creagrutus lepidus, only one other Creagrutus species, C. lassoi, is known from the Rio Aroa basin. The two species can be readily distinguished by the presence of a distinct, vertically elongate humeral mark in C. lassoi, which is absent in C. lepidus, and by the continuous midlateral stripe in C. lepidus, which contrasts with a midlat- eral stripe limited to the posterior one-half to two-thirds of the body in C. lassoi. Creagrutus lepidus is the only member of the genus known from the Rio Urama system. REMARKS.—Subsequent to the description of Creagrutus lepidus, an aquarium specimen of the species was illustrated in color by Evers (1996, cover photo). That author (1996:7) cited the specimen as having originated in northern Venezuela. The exact collection locality (H.G. Evers, in litt.; Johannes, 1996:13) is the Quebrada Aqua Clara, a tributary of the Rio Urama (the latter locality at 10°35'N, 69°16'W), an indepen- dent drainage in the northern portions of Carabobo State. This locality represents a more easterly record for the species rela- tive to its only previous record, the Rio Aroa basin. We know of no specimens of the species from the Rio Yaracuy basin which lies between the Aroa and Urama drainage basins. Inter- estingly, Ceas and Page (1996:671) recently described Chaeto- stoma yurubiense, a species of loricariid cattish, only from the basins of the Rios Aroa, Yaracuy, and Urama, distributional limits matching those of Creagrutus lepidus. GEOGRAPHIC VARIATION.—As far as we are aware, the only population sample of Creagrutus lepidus captured subsequent to its original description (Vari et al., 1993) was a series of specimens collected by Thomas Johannes in the Rio Urama, northern Venezuela (see Evers, 1966; Johannes, 1996). These specimens were kept alive in aquaria, and a subsample, which evidently died in that habitat, were subsequently deposited in the holdings of MTD and borrowed for examination. The four specimens are nearly all larger (38.1-47.1) than the more ex- tensive samples from the Rio Aroa basin (n=42,24.2-42.4 mm SL in 36 specimens). The samples from the two river basins agree in examined meristics and morphometrics, with the only notable feature being that three specimens from the Rio Urama have 11 branched anal-fm rays (fin damaged in fourth speci- men), all at the lower end of the range for this feature within the Rio Aroa samples (11 to 13 branched anal-fin rays). As noted above (see under "Coloration in Alcohol"), various de- tails of head and body pigmentation in the Rio Urama sample show a broader range of variation than found in the series of specimens that were the basis for the original species descrip- tion. It is impossible to determine to what degree, if any, this variation is a consequence of the specimens having been main- tained for a period of time in aquaria. The variation, further- more, overlaps the conditions found in the original population samples from the Rio Aroa system; therefore, we consider the populations from the Rio Aroa to be conspecific with those from the Rio Urama. Additional field-preserved samples from the Rios Aroa and Urama and intervening streams will be nec- essary to determine the significance, if any, of the variation in the limited sample from the Rio Urama relative to conditions in the type series. MATERIAL EXAMINED.—51 specimens (46,24.5-47.1). VENEZUELA. Yaracuy: Sierra de Aroa, Rio Aroa basin, Finca El Jaguar, Quebrada El Charal (approximately 10°32'N, 68°32'W), MHNLS 9659, 1 (37.9, holotype of Creagrutus lep- idus); MHNLS 4144, 12 (27.8-39.2, paratypes of Creagrutus lepidus); MBUCV V-23560, 12 (24.5-37.8; paratypes of Crea- grutus lepidus); USNM 325045, 10 (25.7^2.4; paratypes of Creagrutus lepidus; 2 specimens cleared and counterstained for cartilage and bone); CAS 79520, 7 (26.3-40.1; paratypes of Creagrutus lepidus); MHNLS 4715, 5 (paratypes of Creagru- tus lepidus). Carabobo: Quebrada Aqua Clara, tributary of Rio Urama (latter locality at 10°35'N, 69°16'W), MTD F 17701-17704,4 (38.1-47.1). Creagrutus machadoi, new species FIGURES 51,54, TABLE 29 DIAGNOSIS.—The combination of the possession of premax- illary dentition arranged in the three components generalized for most of the species of Creagrutus and Piabina without a distinctly larger gap between the first and second teeth of the primary series, 6, occasionally 5, teeth in the rimary series of each premaxilla, 2 to 4 maxillary teeth, 5 teeth on each dentary, 8 or 9 predorsal median scales, 38 or 39 lateral line scales with- out a lamellar process over each pore, 4 scale rows between the dorsal-fin origin and the lateral line, 3 scale rows between the anal-fin origin and the lateral line, 9 or 10 branched anal-fin NUMBER 613 135 TABLE 29.—Morphometrics and meristics of Creagrutus machadoi, new spe- cies: (A) holotype of C. machadoi, MCNG 18852; and (B) paratypes of C. machadoi (n= 11). Standard length is expressed in mm; measurements 1 to 14= percentages of standard length; 15 to 18=percentages of head length. Characters Standard length 1. Snout to anal-fin origin 2. Snout to pelvic-fin insertion 3. Snout to pectoral-fin insertion 4. Snout to dorsal-fin origin 5. Dorsal-fin origin to hypural joint 6. Dorsal-fin origin to anal-fin origin 7. Dorsal-fin origin to pelvic-fin insertion 8. Dorsal-fin origin to pectoral-fin insertion 9. Caudal peduncle depth 10. Pectoral-fin length 11. Pelvic-fin length 12. Dorsal-fin length 13. Anal-fin length 14. Head length 15. Postorbital head length 16. Snout length 17. Bony orbital diameter 18. Interorbital width lateral line scales Scale rows between dorsal-fin origin and lateral line Scale rows between anal-fin origin and lateral line Predorsal median scales Branched dorsal-fin rays Branched anal-fin rays Branched pelvic-fin rays Pectoral-fin rays Vertebrae A B Morphometrics 43.8 66.6 49.4 26.3 48.0 55.2 30.4 26.3 32.1 11.1 21.7 15.6 23.0 19.1 28.1 43.8 28.5 35.1 27.8 26.7-44.5 62.4-67.7 46.9-52.1 25.6-27.6 46.4-49.3 51.8-55.9 25.9-28.3 20.9-24.4 28.3-31.1 9.9-11.2 18.1-21.7 14.2-16.4 20.4-24.0 17.5-19.6 26.2-29.8 38.4-^*3.4 25.5-32.0 33.5^3.0 26.1-30.1 Meristics 39 4 3 8 8 10 5-6' 13 37 38-39 4 3 8-9 8 9-10 6-72 11-13 36-38 'Five branched pelvic-fin rays with 1 unbranched medial ray present on left side and 6 branched and 1 unbranched medial ray present on right side of holotype. 2Medial pelvic-fin ray unbranched when 6 branched rays present; 7 branched rays present in only 1 specimen. rays, 5 to 7 gill rakers on the upper limb and 10 or 11 gill rakers on the lower limb of the first gill arch, the distance from the snout to the dorsal-fin origin (46.4%-49.3% of SL), the dis- tance from the dorsal-fin origin to the hypural joint (51.8%—55.9% of SL), the distance from the dorsal-fin origin to the anal-fin origin (25.9%-30.4% of SL), the distance from the dorsal-fin origin to the pelvic-fin insertion (20.9%-26.3% of SL), the postorbital head length (38.4%-43.8% of HL), the interorbital width (26.1%-30.1% of HL), the bony orbital di- ameter (33.5%-43.0% of HL), the gap between the ventral margin of the third infraorbital and the horizontal limb of the preopercle, the absence of a distinct spot of dark pigmentation at the base of the middle caudal-fin rays, the vertical humeral mark without a secondary, dorsal patch of pigmentation, the absence of a distinct patch of pigmentation on the dorsal fin, and the lack of a series of dark spots along the midlateral sur- face of the body distinguishes Creagrutus machadoi within the clade formed by Creagrutus and Piabina. DESCRIPTION.—Morphometric and meristic data for Crea- grutus machadoi in Table 29. Body fusiform to slightly com- pressed. Greatest body depth 1 or 2 scale rows anterior of base of anteriormost dorsal-fin ray. Dorsal profile of head distinctly convex from margin of upper lip to vertical through anterior margin of orbit, straight from that point across dorsal surface of head to posterior tip of supraoccipital spine. Predorsal profile of body with distinct, but shallow, convexity from tip of su- praoccipital to origin of first dorsal-fin ray. Dorsal profile of body straight to slightly concave from dorsal-fin origin to ante- rior procurrent caudal-fin ray. Ventral profile of lower jaw broadly rounded. Ventral profile of body slightly convex from isthmus to pelvic-fin insertion; straight to slightly convex from anterior anal-fin ray posteriorly to caudal peduncle. Anterior profile of head forming broadly rounded angle ranging from as low as approximately 90 degrees to about 120 degrees, with its apex located on horizontal plane through ven- tral portion of orbit. Angle in profile on central portion of lower jaw not as highly accentuated as in many Creagrutus species. Upper jaw longer than, and overhanging, lower jaw, with up to three anterior premaxillary teeth projecting anterior of lower lip. Anterior portion of snout relatively soft and fleshy, with concentration of soft tissues. Minute papillae con- centrated on snout and area between nostrils, upper lip, and continuing into mouth on fleshy flaps and plicae between outer and medial premaxillary teeth. Lower jaw distinctly fleshy an- teriorly, with papillae concentrated on lip and extending ven- trally in decreasing concentrations along surfaces of jaw. Inner surfaces of lower lip convolute and papillose, with fleshy flaps extending into mouth. Papillae apparently absent on isthmus and cheek. Elements of infraorbital series moderately well developed, with gap separating posterior and posteroventral margins of in- fraorbitals from vertical limb of preopercle equally at most ap- proximately one-half of width of third infraorbital bone. Shape of third infraorbital hemispherical, with greater curvature to posterior margin of infraorbital than that of orbit. Fourth in- fraorbital nearly rectangular. Premaxillary teeth in three distinct series: primary series in form of arch, with 5 (3 of 14 specimens) or 6 unicuspidate to tricuspidate teeth, anteriormost 2 or 3 teeth series unicuspidate; medial, triangular cluster of three large tricuspidate teeth, pos- terior two largest and with most highly developed cusps; and single outer unicuspidate tooth located approximately lateral to, or slightly posterior of, fourth tooth in main row. Maxilla with 2 to 4 weakly tricuspidate flattened teeth. Dentary usually with 5 unicuspidate to weakly tricuspidate teeth. Two anterior dentary teeth largest with distinct, but small, lateral cusps; third tooth tricuspidate and slightly smaller than preceding teeth; re- maining dentary teeth unicuspidate or tricuspidate with indis- tinct lateral cusps and distinctly smaller than anterior three teeth. 136 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY FIGURE 54.—Creagrutus machadoi, new species, holotype, MCNG 18852, 43.8 mm SL; Venezuela, Bolivar, upper Rio Caura, Caflo Yumucukena, within 4 km of its mouth. Dorsal-fin rays ii,8 in all specimens. Dorsal-fin origin lo- cated slightly anterior to vertical through pelvic-fin origin. Dis- tal margin of dorsal fin slightly concave, resulting from elonga- tion of posterior unbranched and anterior 2 or 3 branched rays, and 2 posterior branched rays. Anal-fin rays ii,9—10 or iii,9 (lat- ter in only one specimen). Anal fin with hooks, when present (one 26.5 mm SL specimen; MCNG 18917), singly on third and fourth segments of first branched ray. Distal margin of anal fin slightly sigmoidal, with second unbranched and first and second branched rays forming slightly elongate lobe. Posterior two anal-fin rays longer than immediately preceding rays. Pec- toral-fin rays i,ll to 13, typically 12 to 13. Pectoral fin moder- ately long, extending posteriorly nearly to pelvic-fin origin. Pelvic-fin rays i,6,i or i,7 (only in one specimen) (holotype with i,6,i on one side and i,5,i on other). Hooks on pelvic-fin rays, when present, on medial surfaces of segmented and un- segmented portions of main shaft and medial secondary branches of all branched rays. Pelvic fin relatively long, in some specimens reaching posteriorly slightly beyond anterior anal-fin ray. Posterior margin of body scales smoothly rounded. Pelvic axillary process comprising a single, elongate scale. Gill rakers 5-7+10-11. COLORATION IN ALCOHOL.—Overall pigmentation very poorly developed. Ground coloration very pale straw, with ob- served dark chromatophores very small and punctate, ranging from dark brown to black in most portions of head and body. Dorsal surface of head with scattered, small, dark brown chro- matophores, most concentrated over snout and central portion of upper lip, and extending onto plicate tissues of roof of mouth, dorsal surfaces of frontal and parietal portions of cra- nium, including frontal fontanel. Dark crescent-shaped batch of dark chromatophores located immediately anterior of anterior nares. Little or no dark pigmentation on lateral portions of up- per lip and maxilla and interorbital area. Band of scattered, dark brown chromatophores extending from immediately lat- eral of nares posteroventrally and continuing around ventral and posterior margins of orbit. Dorsal one-half of gill cover in region posterior to orbit with numerous scattered, small, dark chromatophores; number of chromatophores decreasing from posterodorsal region of head ventrally onto upper portion of cheek and gill cover. Lower lip and fleshy portion of jaw speckled with small, black chromatophores; other ventral areas of head unpigmented. Dark body pigmentation diffuse, mostly confined to region dorsal of lateral line. Pigmentation concentrated as vertical bands along anteriormost exposed portion of each scale on four dorsalmost, longitudinal rows of scales. Scattered chromato- phores present in posterior fields of all scales dorsal of lateral line. Small area of middorsal region in area of two median scales with cluster of large dark chromatophores similar in size and color to those of humeral mark. Humeral mark usually in form of anteriorly concave vertical bar without region of par- ticularly dense pigmentation and tapered ventrally to narrow band below lateral line. Flank unpigmented ventral of lateral line except for dark pigmentation associated with humeral bar and posterior portion of lateral stripe, and for very sparsely scattered, dark chromatophores delineating hypaxial myosepta immediately dorsal of anal-fin base. Midlateral stripe highly diffuse anteriorly, with anterior portion overlying first and sec- ond scale rows dorsal of lateral line, becoming more densely pigmented and somewhat wider posteriorly and extending ven- tral of lateral line on posterior portion of caudal peduncle. All unbranched and anterior four branched dorsal-fin rays darkly pigmented, especially along distal one-fourth to one- half of their lengths. Smaller dark pigment cells associated with basal one-half of all dorsal-fin rays. Unbranched and anterior branched anal-fin rays hyaline; remainder of anal fin with small dark chromatophores located along anterior margin and adjacent membrane of each ray. Caudal-fin rays delineated mainly by dark brown pigmentation, with more lightly pig- mented cells over central portion of fin. Caudal fin with distal one-half of dorsal lobe and distal one-fourth of ventral mostly unpigmented. Pelvic and pectoral fins hyaline except in larger (greater than 40 mm SL) specimens, which have dark line of pigmentation delineating lateral pectoral-fin ray and patch of more lightly pigmented chromatophores near tip of longest three or four branched rays. N U M B E R 613 137 ETYMOLOGY.—The specific name, machadoi, is in honor of our coauthor on other papers involving Creagrutus, Antonio Machado-Allison of the Universidad Central de Venezuela, in acknowledgment of his assistance to the authors in the labora- tory and the field through the years, and in recognition his many contributions to our knowledge of Neotropical fishes. ECOLOGY.—A specimen of Creagrutus machadoi prepared for clearing and staining in this study had insects in its stom- ach. DISTRIBUTION.—Creagrutus machadoi is known only from Rio Caura basin, a right bank tributary of the main Rio Orinoco (Figure 51, star). COMPARISONS.—In addition to Creagrutus machadoi, three other members of the genus occur in the Rio Caura basin, C. bolivari, C. phasma, and C. xiphos. Creagrutus machadoi is readily distinguished from these other species by the features cited in "Key to the Creagrutus Species in the Rio Orinoco Ba- sin." MATERIAL EXAMINED.—14 specimens (14,26.5-44.5). HOLOTYPE.—VENEZUELA. Bolivar: Departamento Cedeno, upper Rio Caura, Cano Yumucukena, within 4 km of its mouth, collected by B. Stergios et al., 15 May 1988, MCNG 18852, 1 (43.8). PARATYPES.—11 specimens (11, 26.7^44.5). VENEZUELA. Bolivar: Departamento Cedeno, upper Rio Caura, Cano Yumucukena, within 4 km its mouth, collected with holotype, MCNG 41717, 6 (28.1^4.5); USNM 359641,2 (31.0-38.2). Departamento Cedeno, Rio Caura, at the base of Raudal Sejiato (=Cietao; 5°34TM, 64°19'W), collected by B. Stergios, 22 May 1988, MCNG 18896, 3 (26.7-30.6). NONTYPE SPECIMENS.—2 specimens (2, 26.5-27.7). VENEZUELA. Bolivar: Departamento Cedeno, Rio Caura, Isla Guanaguanadi, MCNG 18917, 2 (26.5-27.7). Creagrutus magoi, new species FIGURES 5 1 , 5 5 , TABLE 30 DIAGNOSIS.—The combination of the possession of premax- illary dentition arranged in the three components generalized for most of the species of Creagrutus and Piabina without a distinctly larger gap between the first and second teeth of the primary series, 6 teeth in the primary series of each premaxilla, 2 or 3 maxillary teeth, 5 teeth on each dentary, 9 to 11 predorsal median scales, 37 to 41 lateral line scales without a lamellar process over each pore, 4, rarely 5, scale rows between the dor- sal-fin origin and the lateral line, 3 scale rows between the anal-fin origin and the lateral line, 11 or 12 branched anal-fin rays, 9 to 11 gill rakers on the upper limb and 13 or 14 gill rak- ers on the lower limb of the first gill arch, the distance from the dorsal-fin origin to the anal-fin origin (29.2%-33.8% of SL), the distance from the dorsal-fin origin to the pelvic-fin inser- tion (24.8%-29.0% of SL), the postorbital head length (39.2%-^6.2% of HL), the interorbital width (30.4%-34.3% of HL), the contact, or near contact, between the ventral margin of TABLE 30.—Morphometrics and meristics of Creagrutus magoi, new species (A) holotype of C. magoi, UF 80477; and (B) paratypes of C. magoi (n=49). Standard length is expressed in mm; measurements 1 to 14=percentages of standard length; 15 to 18=percentages of head length. Characters Standard length 1. Snout to anal-fin origin 2. Snout to pelvic-fin insertion 3. Snout to pectoral-fin insertion 4. Snout to dorsal-fin origin 5. Dorsal-fin origin to hypural joint 6. Dorsal-fin origin to anal-fm origin 7. Dorsal-fin origin to pelvic-fin insertion 8. Dorsal-fin origin to pectoral-fin insertion 9. Caudal peduncle depth 10. Pectoral-fm length 11. Pelvic-fin length 12. Dorsal-fin length 13. Anal-fin length 14. Head length 15. Postorbital head length 16. Snout length 17. Bony orbital diameter 18. Interorbital width Lateral line scales Scale rows between dorsal-fin origin and lateral line Scale rows between anal-fin origin and lateral line Predorsal median scales Branched dorsal-fin rays Branched anal-fin rays Branched pelvic-fin rays Pectoral-fin rays Vertebrae A B Morphometrics 62.9 66.7 49.7 26.1 48.5 54.8 33.7 28.9 32.9 11.8 18.6 15.5 19.4 15.6 27.0 42.4 31.8 31.8 34.2 18.7-64.8 62.3-66.6 46.3-^9.6 24.2-28.8 45.3-48.5 53.7-58.4 29.2-33.8 24.8-29.0 30.1-33.3 10.1-12.2 18.6-21.5 14.8-16.6 19.3-23.4 15.0-18.1 24.9-28.8 39.2^*6.2 27.0-31.9 31.0-37.1 30.4-34.3 Meristics 38 5 3 10 8 12 6 13 37 37-41 4-51 3 9-11 7-82 11-12 6 12-14 36-38 'Five scales between dorsal-fin origin and lateral line present in only 2 of 49 paratypes. 2Seven branched anal-fin rays present in only I of 49 paratypes. the third infraorbital and the horizontal limb of the preopercle, the lack of a distinct spot of dark pigmentation at the base of the middle caudal-fin rays, the vertically elongate humeral mark in the form of an inverted comma without a secondary, dorsal patch of pigmentation, the absence of a distinct patch of pigmentation on the dorsal fin, and the lack of a series of dark spots along the midlateral surface of the body distinguishes Creagrutus magoi within the clade formed by Creagrutus and Piabina. DESCRIPTION.—Morphometric and meristic data for Crea- grutus magoi in Table 30. Head and body relatively robust, more so in anterior portion of body in larger specimens. Great- est body depth at, or sometimes slightly anterior of, dorsal-fin origin. Dorsal profile of head distinctly convex from margin of upper lip to vertical through posterior nostril, slightly convex from that point to above center of orbit and then straight to tip of supraoccipital spine. Interorbital region transversely rounded. Dorsal profile of body slightly convex from tip of su- praoccipital spine to dorsal-fin origin, but without any distinct 138 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY change in alignment relative to dorsal profile of head; convex- ity more pronounced in larger specimens. Dorsal surface of body with obtuse middorsal ridge; ridge more obvious posteri- orly. Ventral profile of head with obtuse angle at anteroventral comer of dentary, angle variably obvious, profile slightly con- vex from angle to isthmus. Prepelvic profile of body barely convex in smaller individuals, only somewhat more convex in certain larger specimens. Prepelvic region of body obtusely flattened transversely. Head obtusely pointed in lateral view, more compressed in dorsal view. Upper jaw longer than, and overhanging, lower jaw. Anterior of snout, particularly anteromedial portion, with numerous papillae. Papillae more concentrated on fleshy upper lip, especially along ventral margin of lip and on folds and pli- cae extending between outer and medial premaxillary teeth. Lower lip with numerous papillae on dorsal surface and scat- tered papillae anteriorly. Infraorbital series well developed in all specimens larger than 30 mm SL, with ventral margin of third infraorbital con- tacting, or nearly contacting, horizontal limb of preopercle. Posterior margins of third through fifth infraorbitals distinctly separated from vertical limb of preopercle in smaller speci- mens; gap decreasing proportionally, but still distinct, in larger specimens. Premaxillary dentition in three series: primary series sig- moid, with 6 tricuspidate teeth, without pronounced gap be- tween first and second tooth of series but with medial tooth separated from contralateral series by distinct gap; triangular cluster of 3 teeth, all larger to distinctly larger than those of pri- mary series; and single tooth of form similar to that of primary series occurring lateral to fourth tooth of primary series. Max- illa with 2 or 3 tricuspidate teeth. Dentary with 5 tricuspidate teeth; second tooth more massive and about one-third longer than first tooth; second tooth more than twice as high as much smaller third tooth; third tooth two and one-half times as high as fourth tooth; fourth tooth slightly larger than fifth tooth. Dorsal-fin rays typically ii,8, rarely ii,7. Dorsal-fin origin ap- proximately at vertical through pelvic-fin insertion. Profile of distal margin of dorsal fin slightly concave. Anal-fin rays iii, 11-12. Profile of distal margin of anal fin concave, with moderate lobe anteriorly in larger individuals. Single mature male having anal-fin hooks on first and second branched rays. Pectoral-fin rays i, 11-13. Tip of pectoral fin falling 1 or 2 scales short of pelvic-fin insertion. Pelvic-fin rays i,6,i. Tip of pelvic fin nearly contacting, or more typically falling 1 scale short of, anal-fin origin. Single mature male with pelvic-fin ray hooks limited to medial branch of all branched rays. Gill rakers 9-11 (9 rare) + 13-14. COLORATION IN ALCOHOL.—Ground coloration tan. Dorsal surface of head in smallest specimens with dense deep-lying pigmentation overlying brain and with scattered, dark chro- matophores on dorsal surface of head and snout. Surface chro- matophore field getting increasingly dense with larger size, with largest individuals having entire dorsal surface of head covered with dense field of small, dark chromatophores ex- tending anteriorly to margin of upper lip and to distal margin of maxilla in larger specimens. Region anterior to nostrils with pigmentation more intense, forming distinct crescent-shaped patch present in specimens of all sizes. Smaller individuals with narrow band of dark pigmentation extending from an- teroventral to nostrils to under orbit; band subsumed into over- all darker pigmentation in that region in larger specimens. Re- gion posterior to orbit and dorsal portion of opercle with scattered, dark chromatophores in smaller specimens, chro- matophore field expanding ventrally in larger individuals. Largest specimens with patch of scattered chromatophores on posteroventral corner of cheek near angle of preopercle. Scales of posterolateral surface of body in smaller specimens with patch of dark chromatophores on basal portion of exposed field. Medium-sized specimens with series of small chromato- phores along posterior margin of scales; chromatophore field becoming progressively wider in larger individuals and form- ing reticulate pattern. Humeral mark obvious and vertically elongate in specimens of all sizes. Mark in form of inverted comma, with main body of mark dorsal to lateral line and with chromatophore field density highest in portion of mark within one and one-half to two scales of dorsal midline. Humeral mark in some individuals extending slightly ventral of lateral line as ventrally tapering patch of chromatophores. Midlateral stripe of deep-lying chromatophores limited to posterior two-thirds of body, more intense posteriorly; merging anteriorly into overall dark pigmentation on lateral surface of the body in larger indi- viduals. Dorsal fin with second unbranched ray and distal portions of first and second branched rays covered with dark stellate chro- matophores. Membranes of all but posterior one or two branched dorsal-fin rays with dispersed dark, irregularly shaped chromatophores. Chromatophore field becoming pro- gressive shorter on distal portions of successive fin mem- branes. First through third unbranched rays along with first and sometimes second branched anal-fin rays unpigmented; other- wise anal-fin rays outlined by small dark chromatophores, par- ticularly basally, with scattered chromatophores on intervening portions of fin membranes. Rays of upper and lower margins of caudal fin along with middle caudal-fin rays outlined to vary- ing degrees by small dark chromatophores; intervening rays hyaline. Large specimens with pronounced darkening of ven- tral caudal-fin rays with pigmentation almost appearing as dark stripe. Pectoral and pelvic fins hyaline, or with some scattered, small, dark chromatophores in larger specimens. ETYMOLOGY.—The specific name, magoi, is in honor of Francisco Mago Leccia, formerly of the Universidad Central de Venezuela, in honor of his major contributions to our under- standing of South American freshwater fishes and for all his as- sistance to the senior author through the years. ECOLOGY.—A portion of the paratype series (ANSP 159834, USNM 353306) and the nontypes collected with them (ANSP NUMBER 613 139 FIGURE 55.—Creagrutus magoi. new species, holotype, UF 80477, 62.9 mm SL; Venezuela, Bolivar, Rio Chaviripa, where crossed by bridge on road from Caicara to San Fernando de Atabapo (approximately 7°1 I'M, 66°18'W). 177716) were collected in a cano of up to 1.5 m depth over a bottom of sand, bedrock, aquatic vegetation, and debris. DISTRIBUTION.—Creagrutus magoi occurs in the Rios Chaviripa and Parguaza, right bank tributaries to the Rio Orinoco in Bolivar, Venezuela (Figure 51, triangles). COMPARISONS.—Within the Rio Orinoco basin Creagrutus magoi is most similar to C. provenzanoi, a species that occurs in the Rio Cataniapo, a right bank tributary to the Rio Orinoco upstream of the range of C. provenzanoi. The two species can be readily distinguished by differences in the number of gill rakers on the upper limb of the first gill arch (9 to 11, rarely 9, in C. magoi versus 7 or 8 in C. provenzanoi), and in the number of scales above the lateral line to the dorsal-fin origin (4, rarely 5, in C. magoi versus 5, very rarely 4, in C. provenzanoi). The two species also differ in the width of the interorbital region (30.4%-34.3% of HL in C. magoi versus 27.4o/(^30.1% of HL in C. provenzanoi). Creagrutus magoi is rather similar in meristics and morpho- metrics to C. ephippiatus of the Rio Siapa, an endemic to a trib- utary to the upper Rio Negro. The species differ, however, in overall body form, which is best reflected in the relative dis- tance from the dorsal-fin origin to the anal-fin origin (29.2%-33.8% of SL in C. magoi versus 27.8%-29.7% of SL in C. ephippiatus), and in details of pigmentation (form of hu- meral mark and pigmentation of middle caudal-fin rays). The species also have a pronounced modal shift in the number of total vertebrae (C. magoi: 36(6), 37(38), 38(2) versus C. ephip- piatus: 38 (34), 39(10), 40(1)). GEOGRAPHIC VARIATION.—Available specimens of Crea- grutus magoi originated in two right bank tributaries of the Rio Orinoco, the Rio Chaviripa, and the Rio Parguaza. The samples from these basins agree in morphometrics and meristics, but the population sample from the Rio Parguaza has more intense development of body, head, and caudal-fin pigmentation. MATERIAL EXAMINED.—203 specimens (50, 18.7-64.8). HOLOTYPE.—VENEZUELA. Bolivar. Rio Chaviripa, where crossed by bridge on road from Caicara to San Fernando de Atabapo (approximately 7O11TM, 66°18'W), collected by D.C. Taphorn et al., 14 Apr 1984, UF 80477, 1 (62.9). P A R A T Y P E S . ^ 9 (49, 18.7-64.8). VENEZUELA. Bolivar: Rio Chaviripa, where crossed by bridge on road from Caicara to San Fernando de Atabapo (ap- proximately 7° 1 1 % 66°18'W), collected with holotype, UF 11079, 6 (30.2-55.9); USNM 353864, 2 (56.3-58.6; 1 speci- men cleared and counterstained for cartilage and bone). Rio Chaviripa, where crossed by bridge on road from Caicara to San Fernando de Atabapo (approximately 7°11'N, 66°18'W), collected by D.C. Taphorn et al., 6 Apr 1984, UF 80423, 5 (26.8-57.9); USNM 353863, 1 (42.2). Cano 15.1 km E of ferry crossing on Rio Parguaza along road from Caicara to Puerto Ayacucho (approximately 6°26'28"N, 67°09'24"W), collected by B. Chernoff et al., Nov 1985, MBUCV V-17787, 8 (18.7-64.8); USNM 355118, 2 (30.9^8.2); ANSP 159834, 10 (32.7-56.9); USNM 353305, 2 (38.8-44.6). Cano 8 km N of Ciudad Bolivar to Caicara highway on Las Majadas Road, Rio Chimaico crossing (7°32'30"N, 64°47'W), collected by W. Saul et al., ANSP 159835, 10 (27.5-49.7); USNM 353306, 2 (36.0-50.9). Rio Agua Blanca, from 100 to 600 m below bridge at crossing of Caicara-Ciudad Bolivar Highway (7°50'N, 63O51'18"W), collected by B. Chernoff et al., 21 Nov 1985, ANSP 161405, 1(40.8). NONTYPE SPECIMENS.—153 specimens. VENEZUELA. Bolivar: Cano 15.1 km E of ferry crossing on Rio Parguaza along road from Caicara to Puerto Ayacucho (ap- proximately 6°26'28"N, 67°09'24"W), ANSP 177714, 118. Cano 8 km N of Ciudad Bolivar to Caicara highway on Las Majadas Road, Rio Chimaico crossing (7°32'30"N, 64°47'W), ANSP 177715, 28. Rio Agua Blanca, from 100 to 600 m below bridge at crossing of Caicara-Ciudad Bolivar Highway (7°5(TN, 63°51'18"W), ANSP 177716,7. 140 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY Creagrutus manu, new species FIGURES 51, 56, T A B L E 31 DIAGNOSIS.—The combination of the possession of premax- illary dentition arranged in the three components generalized for most of the species of Creagrutus and Piabina without a distinctly larger gap between the first and second teeth of the primary series, 6, rarely 5, teeth in the primary series on the premaxilla, 2 or 3 teeth on the maxilla, 5 teeth on each dentary, 36 or 37 vertebrae, 13 to 15 branched anal-fin rays, 10 or 11 predorsal median scales, 5 scale rows between the lateral line and the dorsal-fin origin, 6 gill rakers on the upper limb and 12 gill rakers on the lower limb of the first gill arch, the distance from the dorsal-fin origin to the anal-fin origin (33.8%-37.5% of SL), the caudal-peduncle depth (11.9%-13.1% of SL), the postorbital head length (39.5%-46.3% of HL), the bony orbital diameter (31.1%-36.0% of SL), the lack of a series of dark midlateral spots on the body, the vertically elongate humeral mark, and the laterally compressed, relatively deep body distin- guish C. manu from Piabina argentea and all congeners other than C. barrigai and C. pearsoni. Creagrutus manu can be sep- arated from C. barrigai by the distance from the snout to the anal-fin origin (63.5%-66.4% of SL versus 58.5%-63.4% of SL, respectively), and the presence in C. manu of a dark mid- lateral stripe that is absent in C. barrigai. Creagrutus manu can, in turn, be discriminated from C. pearsoni by a distinct midlateral body stripe, which is absent in C. pearsoni, and by differences in the distance from the snout to the anal-fin origin (63.5%-66.4% of SL versus 59.0%-61.9% of SL, respec- tively), and the anal-fin length (20.4%-21.8% of SL versus 15.6%-17.4% of SL, respectively). DESCRIPTION.—Morphometric and meristic data for Crea- grutus manu in Table 31. Head and body moderately com- pressed laterally compared with most other Creagrutus species. Greatest body depth at or slightly anterior to dorsal-fin origin. Dorsal profile of head distinctly convex from margin of upper lip to vertical through posterior nostril, straight from that point to tip of supraoccipital spine. Interorbital region distinctly con- vex transversely. Predorsal profile of body smoothly slightly convex and without change in alignment relative to dorsal pro- file of head in smaller individuals. Convexity more pro- nounced, with distinct change in alignment of predorsal profile relative to that of head in larger specimens. Predorsal midline with obtuse median ridge. Ventral profile of head with obtuse angle at anteroventral angle of dentary, nearly straight from that point to isthmus. Ventral profile of body slightly convex from isthmus to anal fin, convexity more pronounced in larger individuals. Prepelvic region of body transversely rounded. Head obtusely rounded in lateral view, somewhat com- pressed in dorsal view. Upper jaw longer than, and overhang- ing, lower jaw, somewhat less so in larger individuals. Snout fleshy anteromedially with scattered papillae in that region. Pa- pillae also distributed on lateral surface of upper jaw, and on folds and plicae extending between outer and medial premaxil- TABLE 31.—Morphometrics and meristics of Creagrutus manu, new species: (A) holotype of C. manu, MUSM 8867; and (B) paratypes of C. manu (n=5). Standard length is expressed in mm; measurements 1 to 14=percentages of standard length; 15 to 18=percentages of head length. Characters Standard length 1. Snout to anal-fm origin 2. Snout to pelvic-fin insertion 3. Snout to pectoral-fm insertion 4. Snout to dorsal-fin origin 5. Dorsal-fin origin to hypural joint 6. Dorsal-fin origin to anal-fin origin 7. Dorsal-fin origin to pelvic-fin insertion 8. Dorsal-fin origin to pectoral-fin insertion 9. Caudal peduncle depth 10. Pectoral-fin length 11. Pelvic-fin length 12. Dorsal-fin length 13. Anal-fin length 14. Head length 15. Postorbital head length 16. Snout length 17. Bony orbital diameter 18. Interorbital width Lateral line scales Scale rows between dorsal-fin origin and lateral line Scale rows between anal-fin origin and lateral line Predorsal median scales Branched dorsal-fin rays Branched anal-fin rays Branched pelvic-fin rays Pectoral-fin rays Vertebrae A B Morphometrics 39.7 65.3 47.1 25.4 47.6 54.4 37.5 34.5 40.3 13.1 18.4 17.4 22.6 21.4 27.2 46.3 25.9 32.4 28.8 26.1-39.3 63.5-66.4 46.0-47.6 24.4-25.5 49.5-53.4 52.4-55.8 33.8-37.5 30.5-33.8 35.1-39.6 11.9-13.1 19.0-20.7 15.6-17.3 23.0-26.2 20.4-21.8 25.6-28.0 39.5-46.2 23.0-26.7 31.1-36.0 28.0-32.6 Meristics 37 5 4 11 8 15 6 12 36 37-38 5 1-A 10-11 8 13-15 6 12-13 36' Thirty-seven vertebrae present in 2 of 11 nontype specimens (see also com- ments under "Remarks"). lary teeth. Lower lip fleshy anteriorly, with numerous papillae along dorsal surface and scattered papillae on anteromedial portion. Infraorbital series moderately developed. Third infraorbital with posteroventral margin curved and central portion of ven- tral margin of third infraorbital most closely approaching but falling short of horizontal limb of preopercle. Posterior margins of third through fifth infraorbitals falling distinctly short of ver- tical limb of preopercle. Premaxillary dentition in three series: primary row slightly sigmoid, consisting of 6, or more rarely 5, teeth, without pro- nounced gap between first and second tooth of series but with medial tooth separated from anterior tooth of contralateral se- ries by distinct gap; triangular cluster of 3 larger teeth; and sin- gle tooth of form similar to that of primary series occurring lat- eral to fourth tooth of primary premaxillary tooth row, or lateral to area of contact of third and fourth teeth in that series. Max- illa with 2 or 3 tricuspidate teeth. Dentary with S teeth; anterior 4 teeth tricuspidate, fifth tooth unicuspidate. First and second NUMBER 613 141 FIGURE 56.—Creagrutus manu, new species, holotype, MUSM 8867, 39.7 mm SL; Peru, Madre de Dios, Rio Manu basin, Parque Nacional Manu, Quebrada Agua Clara (approximately 11°57'S, 71°17'W). teeth distinctly larger than others, subequal, approximately twice height of third tooth; fourth and fifth teeth distinctly smaller and compressed. Dorsal-fin rays ii,8 in all specimens. Dorsal-fin origin some- what posterior of vertical through pelvic-fin insertion. Profile of distal margin of dorsal fin slightly concave. Anal-fin rays ii, or in, 13-15; first unbranched ray short in specimens with 3 un- branched rays. Profile of distal margin of anal fin slightly con- cave, somewhat more so in larger specimens. Hooks typically present on anal-fin rays in mature males of many Creagrutus species not present in examined specimens. Pectoral-fin rays i,l 1-12. Tip of pectoral fin extending posteriorly nearly to pel- vic-fin insertion in smaller specimens, only approximately three-fourths of that distance in larger individuals. Pelvic-fin rays i,6,i in all specimens. Tip of pelvic fin extending posteri- orly to, or slightly beyond, anus. Hooks typically present on pelvic-fin rays in mature males of many Creagrutus species not present in examined specimens. Gill rakers 6+12. COLORATION IN ALCOHOL.—Ground coloration tan. Dorsal surface of head with scattered moderate-sized chromatophores extending anteriorly onto snout. Deep-lying, dark chromato- phores visible on membranes overlying brain. No obvious con- centration of dark chromatophores anterior to nostrils contrary to situation in many congeners. Chromatophores anterior to nostril continuous with narrow band of dark chromatophores along ventral and, to varying degrees, posterior margins of or- bit. Infraorbitals posterior to orbit along with dorsal portion of opercle covered with varying numbers of scattered chromato- phores. Scales of dorsal portion of body with patch of chromato- phores on basal portion of exposed field of scale; chromato- phore field delimited posteriorly by distinct margin. Few scat- tered, dark chromatophores along distal margins of scales. Humeral mark vertically elongate to rotund. All margins of hu- meral mark quite distinct in smaller specimens; chromato- phores of dorsal portion of mark merging into field of dark background chromatophores in larger individuals. Distinct midlateral stripe formed by surface chromatophores present in all examined specimens. Stripe extending from region between vertical approximately through anterior of dorsal fin (larger in- dividuals) or middle of fin (smaller specimens) posteriorly to rear of caudal peduncle. Stripe more intense overall in larger specimens; continuous posteriorly with horizontal stripe ex- tending along middle caudal-fin rays. Dorsal fin with chromatophores scattered over distal two- thirds of all but posterior rays in larger specimens, chromato- phore field less extensive in smaller specimens. Anal fin with most rays variably outlined by small dark chromatophores and with chromatophores scattered over membranes of all but ante- riormost and posteriormost rays; density of chromatophores and extent of chromatophore field greater in larger specimens. Caudal fin with dark horizontal stripe across middle rays. Stripe more intense anteriorly in specimens of all sizes and more obvious in larger individuals, particularly those with overall darker head and body pigmentation. Pectoral and pelvic fins hyaline or with few scattered, dark chromatophores in larger individuals. ETYMOLOGY.—The specific name, manu, refers to the type region of the species, the upper portions of the Rio Manu of southeastern Peru, and to the Parque Nacional de Manu in which all the examined specimens were collected. ECOLOGY.—The type series of Creagrutus manu was col- lected in small forest streams with moderate water current over stone, pebble, and sand bottoms. Stomach contents of the one specimen prepared for clearing and staining in this study consisted solely of chopped up seeds and plant matter. 142 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY DISTRIBUTION.—Creagrutus manu is known only from a limited region in the upper Rio Manu system of southeastern Peru (Figure 51, diamond). REMARKS.—In addition to the type series, a lot of 11 smaller individuals in somewhat poor condition (USNM 352953, MUSM 13933) also was collected at the type locality. The poor condition of these specimens prevented the taking of counts and measurements for most examined features. The only nota- ble difference between these specimens and the type species is the slightly greater range of vertebrae in the nontypes (36 or 37, versus 36 in the holotype and paratypes). MATERIAL EXAMINED.—17 specimens (6, 26.1-39.7). HOLOTYPE.—PERU. Madre de Dios: Provincia Manu, Rio Manu basin, Parque Nacional Manu, Quebrada Agua Clara, first major quebrada on trail 1 leading from Pakitza (approxi- mately 11°57'S, 71°17'W), collected by H. Ortega et al., 13 Sep 1988, MUSM 8867, 1 (39.7). PARATYPES.—5 specimens (5,26.1-39.3). PERU. Madre de Dios: Provincia Manu, Rio Manu basin, Parque Nacional Manu, second major quebrada on trail 1 lead- ing from Pakitza (approximately 11°57'S, 71°17/W), collected by H. Ortega et al . , 17 Sep 1988, USNM 303067, 2 (27.5-28.5). Provincia Manu, Parque Nacional Manu, Pakitza and vicinity (approximately 11°57'S, 71°17/W), collected by H. Ortega, Oct 1987, MUSM 8868, 1 (26.1). Provincia Manu, Parque Nacional Manu, Pakitza, Quebrada Martin Pescador (approximately 11°57'S, 71°17/W), collected by H. Ortega, 28 Sep 1991, USNM 326903, 1 (39.3; specimen cleared and coun- terstained for cartilage and bone). Provincia Manu, Parque Na- cional Manu, Pakitza and vicinity (approximately 11°57'S, 71°17'W), collected by H. Ortega, Oct 1987, USNM 313476, 1 (32.8). NONTYPE SPECIMENS.—11 specimens. PERU. Madre de Dios: Provincia Manu, Rio Manu basin, Parque Nacional Manu, Pakitza, Quebrada Martin Pescador (approximately 11°57'S, 71°17'W), USNM 352953, 6; MUSM 13933, 5. Creagrutus maxillaris (Myers, 1927) FIGURES 57-59, TABLE 32 Creagrudite maxillaris Myers, 1927:118 [type locality: (Brazil, Amazonas), sandbank on the Colombian border Rio Negro, Cucuhy (=Cucui); also from mouth of [Rio] Curamuni (=Curamoni), Rio Cassiquiare (=Casiquiare)].— Eigenmann and Myers, 1929:547 [based on Myers, 1927].—Fowler, 1948:82 [literature summary]; 1975:25 [literature summary; Creagrutus melanzonus Eigenmann incorrectly listed as junior synonym].—Bohlke, 1953:23 [holo- type and paratype depositories].—Roberts, 1967:236 [replacement pattern of jaw teeth].—Myers and Roberts, 1967:248 [discussion of reported ontoge- netic variation in premaxillary dentition in species].—Mago-Leccia, 1970:70 [Venezuela]; 1971:10 [Venezuela, (Amazonas), Rio Casiquiare].—Bohlke and Saul, 1975:28 [transfer to Creagrutus].—Gery and Renno, 1989:3 [denti- tion noted]. Creagrutus maxillaris Bohlke and Saul, 1975:28 [transfer of species from Cre- agrudite to Creagrutus].—Taphorn et al., 1997:71 [cited for Venezuela]. TABLE 32.—Morphometrics and meristics of Creagrutus maxillaris (A) holo- type of C. maxillaris, CAS 30419 (formerly IU 17682); and (B) all other speci- mens of C. maxillaris from which counts and measurements were taken (n= 20). Standard length is expressed in mm; measurements 1 to 14=percentages of standard length; 15 to 18=percentages of head length. Dashes indicate mea- surements that could not be taken because of poor condition of holotype. Characters Standard length 1. Snout to anal-fin origin 2. Snout to pelvic-fin insertion 3. Snout to pectoral-fm insertion 4. Snout to dorsal-fin origin 5. Dorsal-fin origin to hypural joint 6. Dorsal-fin origin to anal-fin origin 7. Dorsal-fin origin to pelvic-fin insertion 8. Dorsal-fin origin to pectoral-fin insertion 9. Caudal peduncle depth 10. Pectoral-fin length 11. Pelvic-fin length 12. Dorsal-fm length 13. Anal-fin length 14. Head length 15. Postorbital head length 16. Snout length 17. Bony orbital diameter 18. Interorbital width Lateral line scales Scale rows between dorsal-fin origin and lateral line Scale rows between anal-fin origin and lateral line Predorsal median scales Branched dorsal-fin rays Branched anal-fm rays Branched pelvic-fin rays Pectoral-fin rays Vertebrae A B Morphometrics 75.2 70.2 51.2 26.0 51.4 51.9 28.9 21.1 30.6 9.1 18.2 13.3 - - 28.7 46.8 28.8 28.7 22.7 34.2-75.2 64.9-70.2 47.0-51.2 23.0-26.4 44.7-51.4 50.6-56.3 26.3-29.1 18.7-22.1 27.0-30.6 8.8-10.0 15.1-18.1 12.5-14.6 17.4-20.2 13.8-15.1 25.1-28.8 40.0-46.6 25.0-29.0 29.1-34.6 21.7-26.8 Meristics 42 4 3 11 8 10 7 13 40 39-42 4 3 9-11 8 8-10 6-7 13-15 38-40 DIAGNOSIS.—The presence of two distinct rows of premaxil- lary teeth, the very elongate, moderately sloping maxilla com- pared to the condition in most congeners, and the presence of 5 median scales between the posterior margin of the anus and the anal-fin origin distinguish Creagrutus maxillaris from all con- geners with the exception of C. cracentis, a species only known from the Rio Tapajos basin. These two species can be differen- tiated by the length of the postorbital portion of the head (40.0%-46.8% of HL in C. maxillaris versus 36.8%-38.0% of HL in C. cracentis), the bony orbital diameter (28.7%-34.6% of HL in C. maxillaris versus 37.0%-40.0% of HL in C. cra- centis), and to a lesser degree on the pectoral-fin length (15.1%-18.2% of SL in C. maxillaris versus 17.9%-20.0% of SL in C. cracentis). DESCRIPTION.—Morphometric and meristic data for Crea- grutus maxillaris in Table 32. Overall appearance of head and body distinctly elongate compared to most congeners; elonga- tion more obvious in smaller individuals. Body proportionally more elongate in specimens smaller than 25 mm SL in which greatest body occurring at vertical through dorsal-fin origin; NUMBER 613 143 FIGURE 57.—Creagrutus maxillaris, holotype, CAS 30419 (formerly IU 17682), 75.2 mm SL; Brazil, Amazonas, Rio Negro at Cucuhy (=Cucui), sandbank on Colombian border. FIGURE 58.—Creagrutus maxillaris, ANSP 161235, 41.8 mm SL; Venezuela, Amazonas, Rio Ventuari, above confluence with Rio Orinoco. position of greatest body depth shifting anteriorly approxi- mately to vertical through tip of pectoral fin with increasing relative body depth in larger individuals. Dorsal profile of head smoothly rounded from margin of upper lip to region of verti- cal through posterior nostril at all body sizes; nearly straight from that point to rear of supraoccipital spine. Interorbital re- gion slightly transversely convex in smaller individuals, flat in larger specimens. Dorsal profile of body slightly convex from tip of supraoccipital spine to dorsal-fin origin, barely angled at dorsal-fin base; straight from rear of dorsal-fin base to caudal peduncle in smaller individuals, slightly convex in that region in larger specimens. Ventral profile of head gently convex along anterior of dentary, nearly straight for much of length of dentary and then to isthmus. Distinct angle at anteroventral cor- ner of dentary obvious in many congeners not apparent in C. maxillaris. Ventral profile of body from isthmus to anal fin nearly straight or very slightly convex in individuals of up to approximately 30 mm SL; convexity more notable, albeit not pronounced, in larger specimens. Head pointed anteriorly in lateral view and more so in dorsal view. Upper jaw slightly longer than, and overhanging, lower jaw. Anterior portion of mouth nearly horizontal. Ventral mar- gin of upper jaw gently curved with jaw relatively longer than in all other Creagrutus species with exception of C. cracentis. Anterior surface of snout not as fleshy as in congeners other than C. cracentis; with numerous minute papillae over anterior surface. Papillae also line ventral margin of upper lip, dorsal margin of lower lip, and anterior and anterolateral surfaces of lower jaw. Plicae and fleshy flaps extending between premaxil- lary teeth of most Creagrutus species absent. Lower lip not as fleshy anteriorly as in other Creagrutus species. Infraorbital series well developed. Ventral margin of third in- fraorbital in contact, or nearly in contact, with horizontal limb of preopercle for much of its length. Posterior margins of third through fifth infraorbitals slightly separated from vertical limb of preopercle, separation between fifth infraorbital and preo- percle very slight in larger specimens. Premaxillary dentition unusual for Creagrutus species, with only two distinct rows of teeth. Outer row consisting of 3 teeth arranged in slightly irregular series. First and third teeth uni- cuspidate with medially recurved distal portions, middle tooth with very weak lateral cusps and slight medial curvature of central cusp. Inner tooth row consisting of 4 tricuspidate teeth, with middle cusp of each tooth distinctly stronger. Elongate maxilla with 10 to 12 tricuspidate teeth. Maxillary teeth with central cusp longer and typically somewhat posteroventrally recurved. Dentary teeth 10 to 12; anterior 3 teeth largest, teeth following those becoming progressively smaller. Dentary teeth 144 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY FIGURE 59.—Map of central and northern South America showing geographic distribution of Creagrulus maxil- laris (dots, 1 =type locality, 2=geographically disjunct population tentatively identified as C. maxillaris), Crea- grulus melanzonus (squares, 3=type locality), Creagrulus melasma (stars, 4=type locality), Creagrutus menezesi (diamonds, 5=type locality, 6=geographically disjunct population tentatively identified as C. menezesi), and Creagrutus meridionalis (triangles, 7=type locality) (some symbols represent more than one locality or lot of specimens). tricuspidate with central cusp stronger in smaller individuals, becoming progressively penticuspidate ontogenetically, with central cusp most developed in larger specimens. Dorsal-fin rays ii,8. Dorsal-fin origin anterior to vertical through pelvic-fin insertion. Profile of distal margin of dorsal- fin slightly concave. Anal-fin rays ii,8—10. Profile of distal margin of anal fin concave. Hooks typically occurring on anal- fin rays in mature males of many Creagrutus species not present in examined specimens. Pectoral-fin rays i,12—14; fin extending posteriorly approximately one-half of distance to pelvic-fin insertion, fin proportionally somewhat shorter in larger individuals. Pelvic-fin rays i,6,i in smaller individuals, i,7 in larger specimens. Hooks typically occurring on pelvic-fin rays in mature males of many Creagrutus species not present in examined specimens. Tip of pelvic fin extending posteriorly approximately two-thirds of distance to anus. Gill rakers 7+10-12. COLORATION IN ALCOHOL.—Overall coloration light tan. Dorsal surface of head in smaller individuals covered with su- perficial small, dark chromatophores. Membranes overlying brain covered with larger, dark, stellate chromatophores in smaller specimens. Dark pigmentation overlying brain, if present, masked by thicker bones and intracranial adipose de- posits in larger individuals. Snout and upper jaw with scatter- ing of small dark chromatophores; these slightly more concen- trated anterior to nares in smaller specimens. Larger individuals with additional scattered, dark chromatophores on lower jaw, and dorsal portions of opercle and infraorbital se- ries. Distinct concentration of dark chromatophores present an- NUMBER 613 145 tenor to nares and along ventral and posterior margins of orbit in other Creagrutus species not apparent in C. maxillaris. Dor- solateral portion of body with scattered, dark chromatophores. Dorsal portion of body with small dark chromatophores con- centrated along posterior portion of scales, forming irregular reticulate pattern. Faint band formed by small dark chromato- phores on midlateral surface of body of smaller specimens. Distinction between midlateral band and dark dorsolateral pig- mentation on body becoming increasingly obscure with in- creasing overall body size on anterior portion of body such that band only discrete on posterior one-third of body on specimens larger than approximately 35 mm SL. Presence or absence of distinct midlateral band on posterior portion of body cannot be evaluated in largest examined specimens as a consequence of guanine overlying this region. Humeral mark vertically elon- gate, typically with anterior margin concave; mark extending dorsally from slightly above horizontal through pectoral-fin in- sertion to approximately one scale width from dorsal midline. Pigmentation of humeral mark most intense in region centered along lateral line, variably less intense dorsal and ventral of that area. Dorsal-fin ray margins and membranes with small dark chro- matophores. Basal portions of anal-fin rays outlined by chro- matophores. Caudal fin with dark stripe formed by superficial chromatophores extending over middle caudal-fin rays; stripe more intensely pigmented basally. Deep-lying dark spot appar- ent at base of middle caudal-fin rays in smaller specimens. Stripe on middle caudal-fin rays flanked dorsally and ventrally by 2 or 3 relatively unpigmented rays. Remaining caudal-fin rays and procurrent rays covered with scattered, dark chro- matophores; chromatophores somewhat more concentrated along ray margins. Pectoral and pelvic fins with only few scat- tered, small chromatophores. COMPARISONS.—The distinctive dentition pattern of Crea- grutus maxillaris readily distinguishes it from all of its conge- ners other than C. cracentis. These two species can be discrim- inated by the features cited in the "Diagnosis," above. DISTRIBUTION.—Creagrutus maxillaris is known to occur in the Rio Orinoco basin rivers draining the Guyana shield, the upper Rio Negro in Brazil and Venezuela, and perhaps upper portions of the Rio Madeira system along Brazilian-Bolivian border (Figure 59, dots; see also "Remarks" immediately fol- lowing with respect to some locality records). REMARKS.—The material of Creagrutus maxillaris exam- ined in this study has a notably disjunct distribution relative to the more compact ranges of most members of the genus. Most population samples of C. maxillaris originated in the upper portions of Rio Negro in northern Brazil and southern Venezu- ela and in the upper Rio Orinoco in southern Venezuela. Out- side of this area, a single specimen originated in the Rio Aro, a southern tributary of the Rio Orinoco, and a single sample is from the upper portions of Rio Madeira basin along the Boliv- ian-Brazilian border (Figure 59, dot indicated by 2). The single specimen from the lower portions of the Rio Orinoco basin (MCNG 19270), although a major range exten- sion to the northeast, relative to the other records of this species in Venezuela, nonetheless originated in a river draining the Guyana shield; a pattern common to the other samples of the species in that region. This specimen from the lower portions of the Orinoco basin cannot be discriminated from the popula- tion samples of C. maxillaris that originated in the upper Rio Orinoco and Rio Negro. The series of 15 specimens from the Rio Madeira system (AMNH 39855), herein identified as Creagrutus maxillaris, largely lack scales and are in relatively poor overall condition, precluding a definitive identification, but they are either that species or a very similar form. A determination of whether the Rio Madeira population is conspecific with the populations in the Rios Orinoco and Negro must await the examination of other specimens in good condition from the Rio Madeira. In his original description of Creagrudite maxillaris and in a subsequent publication, Myers (1927:117; 1958:29) proposed that the species underwent an ontogenetic shift from three rows of premaxillary teeth in juveniles, the condition typical for Cre- agrutus, to two rows in larger specimens, an unusual shift in characiforms (Note: the descriptive system for premaxillary dentition utilized by Myers (1927) differs from that used herein). Myers and Roberts (1967:248) corrected this observa- tion and noted that the presumed change in the number of pre- maxillary tooth rows was rather a consequence of the complex nature of the type series of Creagrudite maxillaris. These au- thors reported that the smaller specimens with three rows of teeth cited by Myers (1927) as Creagrudite maxillaris were ac- tually individuals of Creagrutus melanzonus Eigenmann. The results of this study indicate, however, that the material identi- fied as the latter species from the upper Rio Negro, the type re- gion of Creagrudite maxillaris, is actually Creagrutus zephyrus. The examination of a series of specimens of C. max- illaris of various body sizes does not reveal any ontogenetic differences in the number of tooth rows, only an ontogenetic increase in the number of cusps on the jaw teeth. It is unclear whether Myers' association of Creagrudite with Creagrutus was a consequence of the admixture in the type se- ries of Creagrudite maxillaris of specimens of Creagrutus zephyrus (see comments in previous paragraph). No other basis is apparent for his statement that Creagrudite maxillaris is a "specialized Creagrutus" (Myers, 1927:118). Bohlke and Saul (1975:27), in their description of Creagrutus gephyrus, synon- ymized Creagrudite into Creagrutus because, in their opinion, their new species bridged the morphological gap between the two nominal genera. The phylogenetic results of this study sup- port the inclusion of Creagrudite in Creagrutus. Fowler (1975:25) listed Creagrutus melanzonus Eigenmann as a junior synonym of Creagrudite maxillaris {-Creagrutus maxillaris of this study) but did not detail the basis for this syn- onymy. Although the two species have elongate heads and bod- ies, they differ in numerous features, most notably in their ar- 146 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY rangements of premaxillary teeth, and they and have totally allopatric distributions under the results of this study. MATERIAL EXAMINED.—60 specimens (20, 34.2-75.2). BRAZIL. Amazonas: Rio Negro, Cucuhy (=Cucui), sand- bank on the Colombian border (1°12'N, 66°50'W), CAS 30419, 1 (75.2, holotype of Creagrudite maxillaris; formerly IU 17682); MCZ 31572, 1 (71.5, paratype of Creagrudite max- illaris); CAS 157925, 1 (67.7). Rio Negro, Parana do Jacare (0°30'S, 66°30'W), USNM 330354, 1. VENEZUELA. Amazonas: Rio Casiquiare, mouth of the Curamuni (?=Rio Curamoni or Guramoni, 2°37'N, 66°12'W), CAS 30420,2 (39.1^6.0, paratypes of Creagrudite maxillaris; formerly IU 17684); CAS 158030, 7 (formerly SU 58030); CAS 158988, 2. Playa and side channel of Rio Ventuari, ap- proximately 12 km above confluence with Rio Orinoco (4°04'N, 66°56'W), ANSP 161230, 5. Rio Ventuari, approxi- mately 10-12 km above confluence with Rio Orinoco (4°04'N, 66°56'W), ANSP 161235, 6 (34.5-41.8). Rio Orinoco near mouth of Rio Iguapo (3°07'N, 65°28'W), ANSP 161234, 1 (34.2). Rio Casiquiare, near Solano (2°00'N, 66°57'W), USNM 340955, 1 (40.2). Mata de Palma (3°44'N, 67°00'W), CAS 151036, 1 (specimen cleared and stained for bone); CAS 157965, 5 (1, 36.3); CAS 158198, 3; CAS 160469, 7. Rio Aro, Salto El Pajaro, on road to Borbon, near Pefias Negras (latter locality at 7°54'S, 64°18'W), MCNG 19270, 1 (56.0). The following sample is tentatively identified as Creagrutus maxillaris (see comments under "Remarks," above, concerning this identification). BOLIVIA. El Beni: Rio Itenez, approximately 9 km SE of Costa Marquez, AMNH 39855, 15 (5, 34.3-43.2). Creagrutus melanzonus Eigenmann, 1909 FIGURES 59-61, TABLE 33 Creagrutus melanzonus Eigenmann, 1909:30 [British Guiana (=Guyana), Crab Falls, Warraputa, Tumatumari]; 1910:435 [literature compilation]; 1912:347, pi. 45: fig. 1 [redescription based on type series]; 1927:418, pi. 34: fig. 2 [re- description based on type series].—Henn, 1928:63 [holotype in Carnegie Museum].—Myers and Roberts, 1967:248—249 [in part; citation of species from British Guiana (=Guyana); not cited presence of species in "upper Rio Negro-upper Orinoco" system; not cited specimens of C. melanzonus].— Bohlke and Saul, 1975:27, fig. 4b [form of upper jaw; not citation of species from upper Rio Orinoco and upper Rio Negro].—Ibarra and Stewart, 1987:28 [holotype in FMNH].—Planquette et al., 1996:324, fig. [French Guiana, Clique Anne, Fleuve Sinnamary system and Gaa Kaba, Fleuve Ma- roni basin].—Machado-Allison et al., 2000:16 [Venezuela, Rio Cuyuni ba- sin].—Not Bohlke and Saul, 1975:28.—Not Mago-Leccia, 1970:70. Creagrudite melanzonus.—Myers, 1927:119 [Creagrutus melanzonus suggest- ed as juvenile form of Creagrudite].—Fowler, 1975:25 [citation]. Creagrudite melanzona.—Eigenmann and Myers, 1929:546 [Creagrutus melanzonus shifted to Creagrudite and described as based on juveniles]. Creagrudite maxillaris [not of Myers, 1927].—Fowler, 1975:25 [misidentifica- tion] [Creagrutus melanzonus incorrectly listed as synonym]. DIAGNOSIS.—The possession of premaxillary dentition with the three components generalized for the species of Creagru- tus, but with a distinct gap between the first and second teeth of primary tooth row and a forward position of the triangular clus- ter of three posteromedial teeth distinguishes C. melanzonus from all members of the clade formed by Creagrutus and Pia- bina with the exception of Creagrutus maracaiboensis, C. muelleri, C. nigrostigmatus, C. ouranonastes, C. peruanus, C. runa, and Piabina argentea. Creagrutus melanzonus can be distinguished from these seven species by the combination of the possession of 5, occasionally 6, teeth in primary series of each premaxilla, 3 or 4 maxillary teeth, 8 to 10 predorsal me- dian scales, 35 to 38 lateral line scales without a lamellar pro- cess over each pore, 9 to 11 branched anal-fin rays, 35 to 38 vertebrae, the relatively well developed third infraorbital whose ventral margin approaches, but does not contact, the horizontal limb of the preopercle, and the lack of a large spot of dark pigmentation at the base of the middle caudal-fin rays. DESCRIPTION.—Morphometric and meristic data for Crea- grutus melanzonus in Table 33. Body relatively shallow and fusiform to slightly compressed transversely. Greatest body depth at, or slightly anterior of, dorsal-fin origin. Dorsal profile of head distinctly convex from margin of upper lip to vertical through anterior margin of orbit, straight to slightly convex from that point to posterior tip of supraoccipital spine. Dorsal profile of body ranging from straight to slightly and smoothly convex to dorsal-fin origin, straight to slightly concave from that point to anterior adipose-fin base, straight to slightly con- cave from that point to vertical through anterior procurrent cau- dal-fin rays. Ventral profile of head with obtuse angle (shallow convexity in some specimens) approximately midway between margin of lower lip and posterior of dentary, slightly convex from that point to isthmus. Ventral profile of body slightly con- vex from isthmus to anal-fin origin and slightly concave from that point to caudal peduncle. Anterior profile of head forming broadly rounded obtuse an- gle. Upper jaw slightly longer than, and overhanging, lower jaw. Most external surfaces of head covered with minute papil- lae. Anterior portion of snout relatively firm and without con- centration of soft tissues found in that region in many conge- ners, with minute papillae present on snout and upper lip. Papillae continuing into mouth on fleshy flaps and plicae be- tween outer and medial premaxillary teeth. Lower jaw dis- tinctly fleshy anteriorly, inner surfaces of lower lip convolute with papillose flaps. Elements of infraorbital series moderately well developed, with ventral margin of third infraorbital approaching, or barely contacting, horizontal limb of preopercle. Posterior margin of third infraorbital distinctly separated from vertical limb of pre- opercle by gap ranging from one-third to one-half of width of fourth and fifth infraorbital bones. Posterior and ventral mar- gins of third infraorbital broadly rounded and approximately concentric with orbit. Posterior margins of fourth and fifth in- fraorbitals distinctly separated from vertical limb of preopercle. Premaxillary teeth in threeistinct groups: main row typically comprising 5, rarely 4 (1 specimen) or 6 (2 specimens), elon- gate, distally recurved unicuspidate to weakly tricuspidate teeth, anteriormost premaxillary tooth doften unicuspidate and NUMBER 613 147 TABLE 33.—Morphometrics and meristics of Creagrutus melanzonus: (A) holotype of C. melanzonus, FMNH 52705; (B) other specimens of C. melanzonus from Guyana (n= 14; vertebral counts taken from an additional 22 specimens); and (C) specimens of C. melanzonus from French Guiana (n=10). Standard length is expressed in mm; measurements 1 to 14=percentages of standard length; 15 to 18=percentages of head length. Dashes indi- cate values that could not be determined because of damage to holotype. Characters Standard length 1. Snout to anal-fin origin 2. Snout to pelvic-fin insertion 3. Snout to pectoral-fin insertion 4. Snout to dorsal-fin origin 5. Dorsal-fin origin to hypural joint 6. Dorsal-fin origin to anal-fm origin 7. Dorsal-fin origin to pelvic-fin insertion 8. Dorsal-fm origin to pectoral-fin insertion 9. Caudal peduncle depth 10. Pectoral-fin length 11. Pelvic-fin length 12. Dorsal-fin length 13. Anal-fin length 14. Head length 15. Postorbital head length 16. Snout length 17. Bony orbital diameter 18. Interorbital width Lateral line scales Scale rows between dorsal-fin origin and lateral line Scale rows between anal-fin origin and lateral line Predorsal median scales Branched dorsal-fin rays Branched anal-fin rays Branched pelvic-fin rays Pectoral-fin rays Vertebrae A 35.2 65.1 47.2 24.1 48.0 54.3 27.3 21.9 30.7 9.9 17.9 15.1 - - 25.3 41.6 29.2 37.1 27.0 37 4 3 9 8 10 63 13 37 B Morphometrics 22.8-32.0 61.6-68.4 46.2-50.2 23.3-27.0 45.7-52.5 51.7-56.1 23.8-27.4 18.3-22.9 27.9-32.9 9.0-10.5 17.3-20.7 12.8-17.3 19.7-22.4 13.3-18.5 24.4-27.4 35.4-41.7 23.9-33.3 34.8-42.9 25.3-30.3 Meristics 35-381 4' 2_3>.2 8-10 8 9-11 63 11-14 35-384 C 32.4-36.1 60.5-65.5 44.7-48.0 22.2-26.0 44.8-49.2 53.1-57.1 25.5-27.8 20.2-23.6 27.7-30.8 9.0-10.7 16.1-19.3 13.2-14.4 18.7-21.7 16.4-18.5 23.9-27.0 37.3-44.0 25.6-31.9 34.8^1.2 26.6-30.8 36-38 4 3 8-9 8 10-11 6-V 11-13 36-37 'Specimens mostly lacking scales and count estimated from scale pockets. 2Two scales between anal-fin origin and lateral line present in only 1 of 14 specimens. 3Medial pelvic-fin unbranched when 6 branched rays present. 4Thirty-eight vertebrae present in only 3 of 36 nontype specimens from Guyana. always separated from second tooth in series by distinct gap; triangular cluster of three large tricuspidate teeth with anterior tooth occasionally unicuspidate and partially inserted into gap between first and second teeth of primary series; and single elongate, unicuspidate outer tooth positioned lateral to third or fourth tooth in main row. Maxilla with 3 or 4 tricuspidate teeth. Dentary with 6 or 7 tricuspidate teeth with third tooth slightly recurved; first two teeth largest, with second tooth slightly larger than first tooth, third tooth about two-thirds height of second tooth, remaining teeth in series distinctly smaller than anterior three teeth. Dorsal-fin rays ii,8 in all specimens. Dorsal-fin origin lo- cated at, or slightly anterior to, vertical through pelvic-fin in- sertion. Distal margin of dorsal fin nearly straight, with very slight concavity as result of elongation of first 3 or 4 rays. Anal-fin rays ii,9-ll or iii, 11 (in only 1 specimen). Anal fin with hooks, when present, limited to 1 hook per segment on segments of first, or first and second, branched ray (2 hooks observed on 1 segment in one specimen). Distal margin of anal fin slightly sigmoidal, with anterior rays forming relatively elongate lobe and outline of posterior 5 or 6 rays concave. Pec- toral-fin rays i,11-14, typically 11 or 12. Pectoral fin short, tip of fin extending posteriorly maximally to within 2 or 3 scale rows of pelvic-fin insertion. Pelvic-fin rays i,6,i. Tip of pelvic fin approaching, or reaching, anal-fin origin; with hooks on medial surfaces of segmented and unsegmented portions of main shaft and medial secondary branches of all rays medial of the lateral unbranched element. Posterior margin of body scales smoothly rounded to slightly undulate. Gill rakers 4-7+10-12. COLORATION IN ALCOHOL.—Overall ground coloration straw with dark pigmentation ranging from light brown to dark sepia. Dorsal surface of head with diffuse pattern of small, light 148 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY brown chromatophores on upper lip and over snout. Dorsal sur- faces of frontal and parietal portions of cranium uniformly and densely invested with medium- to large-sized, dark brown, deep-lying chromatophores. Distinct small crescent-shaped patch of dark chromatophores located immediately in front of anterior nares. Band of scattered, dark chromatophores extend- ing from immediately lateral of nares posteroventrally and con- tinuing along ventral margin of orbit, but with unpigmented disjunction of band ventral of lens of eye. Lower lip and vent- rolateral surface of head unpigmented with exception of three or four dark chromatophores that may occur over posterior one-half of lower jaw. Reflective guanine not observed in asso- ciation with head or any other body components, although re- ported to be present in association with body stripe by Eigen- mann(1909). Body pigmentation most concentrated dorsally in association with dorsalmost lateral scale row and median scale row, these scales outlined by bands of scattered, dark chromatophores; darkest pigmentation flanking dorsal-fin base, with group of somewhat more concentrated, but still scattered, chromato- phores immediately posterior of supraoccipital spine. Humeral mark usually in form of anteriorly concave crescent, with pig- mentation most concentrated immediately dorsal of lateral line and terminating somewhat abruptly about 2 scale rows dorsal and ventral of lateral line. Dark flank pigmentation, other than humeral bar, in region anterior to vertical through anal-fin ori- gin restricted to area dorsal of lateral line, except for scattered chromatophores associated with myosepta immediately dorsal of anal-fin base. Some specimens with such myoseptal pigmen- tation extending anteriorly to near vertical through pelvic-fin insertion. Dark midlateral body stripe extending to within 2 or 3 scale rows of humeral mark, becoming more densely pig- mented and somewhat wider posteriorly on caudal peduncle. Dorsal-fin membrane with dark chromatophores most con- centrated on distal one-fourth to one-third of anterior 4 branched rays, unbranched rays darkly pigmented. Unbranched anal-fin rays unpigmented except for small number of basal dark chromatophores, proximal one-half of branched rays de- lineated by dark pigmentation along their anterior surfaces. Caudal fin with all fin rays delineated by dark pigmentation, pigmentation darkest on central and ventral rays. Dorsal-fin rays outlined by very small, less densely pigmented chromato- phores, central rays generally darkest, and associated pigmen- tation usually appearing as small diffuse spot. Deep-lying dark pigmentation arranged in vertical line delineating posterior ex- tremities of hypural plates. Pelvic fin hyaline. Pectoral fin ei- ther with scattered, dark chromatophores restricted to distal one-fourth of lateral 4 or 5 rays, or with several isolated chro- matophores scattered over fin. ECOLOGY.—Planquette et al. (1996:324) reported that Crea- grutus melanzonus inhabits creeks with sand bottoms, some- times with gravel and rocks in French Guiana. These authors also noted that the species is relatively rare and frequents the higher portions of rivers. DISTRIBUTION.—Creagrutus melanzonus is known from scattered localities extending from the Rio Cuyuni basin of eastern Venezuela to the Fleuve Sinnamary system of French Guiana (Figure 59, squares). The species is, however, unknown in the region between the Essequibo River in Guyana and the river basin along the Suriname-French Guiana border region (the Marowijne River or Fleuve Maroni, respectively; see also comments under "Creagrutus in Cis-Andean South America," above). REMARKS.—Myers and Roberts (1967:248) identified speci- mens form the "Upper Orinoco-Upper Negro" as Creagrutus melanzonus. This identification has been followed by subse- quent authors (Mago-Leccia, 1970; Bohlke and Saul, 1975; Gery and Renno, 1989), but analysis has shown that the popu- lation samples identified as C. melanzonus, which originated from that region, are instead representatives of a distinct spe- cies, C. zephyrus. Myers (1927:117-119), in his original description of Crea- grudite maxillaris, reported that the species underwent an onto- genetic shift from three to two rows of premaxillary dentition. Myers and Roberts (1967:248) noted that the original series of specimens on which Myers (1927) based his description of C. maxillaris was complex, and that the small specimens in the se- ries were actually Creagrutus melanzonus. This problem also was commented on by Bohlke and Saul (1975). The specimens on which the original description of Creagrudite maxillaris were based all originated within the known range of Creagru- tus zephyrus in the upper Rio Negro system, an area distant from the known range of C. melanzonus. These records are consequently considered to represent C. zephyrus. Mago-Leccia (1970:70) reported C. melanzonus from Vene- zuela. This report presumably was based on Myers and Roberts (1967) who, in turn, had based their records on specimens from southern Venezuela. Although those populations are considered herein to be C. zephyrus, C. melanzonus is, nonetheless, present in eastern Venezuela in the Rio Cuyuni basin, which forms the northwestern portion of the Essequibo River system. Myers (1927:119) followed by Eigenmann and Myers (1929:546) proposed that Creagrutus melanzonus was most closely related to Creagrudite maxillaris and shifted the former species to Creagrudite. The available evidence does not sup- port such an association (see "Intrageneric Relationships within Creagrutus" above) and Creagrudite is furthermore herein considered a synonym of Creagrutus (see "Synonymy of Creagrutus" above). A possible misinterpretation of the shift of Creagrutus melanzonus to Creagrudite by Myers (1927:119) and Eigen- mann and Myers (1929:546) may have led Fowler (1975:25) to place Creagrutus melanzonus as a synonym of Creagrudite maxillaris. The species differ in numerous features, in particu- lar their dentition, so such a synonymy is unjustified. MATERIAL EXAMINED.—81 specimens (46,22.8-36.1). VENEZUELA. Bolivar: "charco" 7 km west of Anacoco (lat- ter locality at 6°43'N, 61°08'W), upper Rio Cuyuni basin, MCNG 1031,20(28.5-30.9). NUMBER 613 149 FIGURE 60.—Creagrutus melanzonus, ANSP 176596, 33.4 mm SL; Guyana, Essequibo River, extensive sandbar 500 m downstream from Paddle Rock campsite (4°44TM, 58°43'W). FIGURE 61 .—Creagrutus melanzonus, MHNG 2183.45, 35.6 mm SL; French Guiana, Maroni, Gaa Kaba. GUYANA. Crab Falls, Essequibo River (5°24'N, 58°51 'W), FMNH 52705, 1 (35.2, holotype of Creagrutus melanzonus; formerly CM 1067). Essequibo River, Warraputa (=Warraputa (=Waraputa, S0^^ 58°50'W), FMNH 52706, 1 (paratype of Creagrutus melanzonus; formerly CM 1068); CAS 30421, 1 (paratype of Creagrutus melanzonus; formerly IU 11753). Lower Potaro River, Tumatumari (5°22'N, 59°00'W), FMNH 72707, 1 (32.0, paratype of Creagrutus melanzonus; formerly CM 1069); CAS 30422, 2 (paratypes of Creagrutus melanzo- nus; formerly IU 11754). Mazaruni-Potaro District: Little Takutu River, AMNH 72990, 9 (22.8-29.2). Mazaruni River, 5 km W of Issano (05°49'05"N, 59°28'09"W), ROM 70239, 4 (26.4-28.6). Isolated stagnant pool/pond about 40 m from main channel of Essequibo River (04°32'43"N, 58°35'02"W), ANSP 175688, 1. Essequibo River, sand bar (4°44'N, 58°43'W), ANSP 176597, 10 (of 72). Essequibo River, sand bar (4°44'22"N, 58°42'23"W), ANSP 176598, 3 (of 6). Essequibo River, extensive sandbar 500 m downstream from Paddle Rock campsite (4°44'N, 58°43'W), ANSP 176596, 10 (of 22). SURINAME. Marowijne District: Oelemari River, 2 km N of Oelemari airstrip (latter locality at 3°06'N, 54°32'W), ZMA 107.557, 1 (27.2). FRENCH GUIANA. Fleuve Maroni basin, Gaa Kaba (4°28'N, 54°24'W), MHNG 2183.45, 6 (32.4-35.6). Fleuve Sinnamary basin, Saut Takari Tante (approximately 4°35'N, 52°56'W), ORSTOM 1015, 2 (32.5-36.1). Fleuve Sinnamary basin, Crique des Freres Anicet (approximately 4°09'N, 52°58'W), ORSTOM 6007, 2 (33.5-36.1). Fleuve Sinnamary basin, Crique Anne (approximately 4°33X 52°50'W), ORSTOM un- cataloged, 7. Creagrutus melasma Vari, Harold, and Taphorn, 1994 FIGURES 59, 62, TABLE 34 Creagrutus beni [not of Eigenmann 1911].—Eigenmann 1920:12 [misidentifi- cation] [Venezuela, Carabobo, Lago de Valencia and adjoining rivers; speci- mens from Maracay, IU 15133, and Isla del Buro (=Isla El Burro), IU 15134]; 1927:422 [in part; specimens from Venezuela, Carabobo, Maracay, IU 15133, and Isla del Buro (=Isla El Burro), IU 15134].—Pearse 1920:12, 24, 25,43 [Venezuela, Carabobo, Lago de Valencia; food items and parasites; specimens served as basis for Eigenmann 1920 and 1927 citations].—Ro- man, 1992:169 [color photo; common name; cited distribution in (Rio) Orinoco and Lago de Valencia; not cited occurrence in Amazon basin].— Baensch and Riehl, 1993:270, photo on page 271 [life coloration, breeding]. Creagrutus species.—Gery, 1977:392, 407 [color plate, in key]. Creagrutus sp.—Winemiller, 1989:239 [Venezuela: Rio Apure, Cano Volcan; life history attributes]; 1990:364 [Venezuela: Rio Apure basin. Cano Volcan]. Creagrutus n. sp.—Taphom, 1992:173-175 [Venezuela, Rio Apure basin; nat- ural history; common name]. Creagrutus melasma Vari et al.. 1994:90, fig. 1 [type locality: Venezuela, Guar- ico, Parque Nacional Guatopo, Rio Oriruco, first bridge along road from Santa Teresa to Altagracia],—Weitzman et al., 1996, fig. 1 [life colora- tion].—Sabaj et al., 1997:269 [paratype depository].—Lasso et al., 1997:42 [paratype depository]. Creagrutus melasmus.—Taphom et al., 1997:71 [cited for Venezuela]. DIAGNOSIS.—The combination of the possession of premax- illary dentition arranged in the three components generalized for most of the species of Creagrutus and Piabina without a distinctly larger gap between the first and second teeth of the 150 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY TABLE 34.—Morphometrics and meristics of Creagrulus melasma: (A) holo- type of C. melasma, MBUCV V-22918; and (B) paratypes of C. melasma from which counts and measurements were taken (n=15). Standard length is ex- pressed in mm; measurements 1 to 14-percentages of standard length; 15 to 18=percentages of head length. Characters Standard Length 1. Snout to anal-fm origin 2. Snout to pelvic-fin insertion 3. Snout to pectoral-fm insertion 4. Snout to dorsal-fin origin 5. Dorsal-fin origin to hypural joint 6. Dorsal-fin origin to anal-fin origin 7. Dorsal-fin origin to pelvic-fin insertion 8. Dorsal-fin origin to pectoral-fin insertion 9. Caudal peduncle depth 10. Pectoral-fin length 11. Pelvic-fin length 12. Dorsal-fin length 13. Anal-fin length 14. Head length 15. Postorbital head length 16. Snout length 17. Bony orbital diameter 18. Interorbital width Lateral line scales Scale rows between dorsal-fin origin and lateral line Scale rows between anal-fin origin and lateral line Predorsal median scales Branched dorsal-fin rays Branched anal-fin rays Branched pelvic-fin rays Pectoral-fin rays Vertebrae A B Morphometrics 32.4 61.4 47.7 26.5 49.8 56.9 31.3 30.2 34.5 11.9 21.3 15.9 25.7 21.3 26.4 43.8 28.3 32.8 31.9 22.8-^0.7 61.9-66.7 46.8-51.2 24.3-27.2 48.4-53.8 53.3-57.7 30.7-36.8 29.0-35.2 32.5-39.0 11.5-13.1 18.7-21.5 14.8-16.7 21.4-28.5 18.6-21.6 24.5-26.9 42.4--47.8 24.0-29.0 30.9-36.2 29.3-34.7 Meristics 35 5 4 10 8 11 7 11 35 34-36 5-6 4-5 10-11 7-8 0-12 7 11-13 34-36 primary series, 2 or 3 teeth on the maxilla, 5 teeth in the pri- mary tooth row of the premaxilla, 6 dentary teeth, 34 to 36 lat- eral line scales without a lamellar process over each pore, 10 or 11 predorsal median scales, 5 or 6 scale rows between the dor- sal-fin origin and the lateral line, 34 to 36 vertebrae, 10 to 12 branched anal-fin rays, 10 to 12 gill rakers on the lower portion of the first gill arch, 2 post-anal median scales to the anal-fin origin, the snout length (24.0%-29.0% of HL), the poorly de- veloped third infraorbital with the curvature of posteroventral margin of the bone roughly concentric with the orbital margin and with the ventral margin of the third infraorbital distinctly separated from the horizontal limb of the preopercle, the lack of a series of dark midlateral spots on the body, the vertically elongate humeral mark, and a discrete patch of dark pigmenta- tion on the middle portion of the anterior dorsal-fin rays distin- guishes Creagrutus melasma within the clade composed of Creagrutus and Piabina. DESCRIPTION.—Morphometric and meristic data for Crea- grutus melasma in Table 34. Maximum body depth along verti- cal through pelvic-fin insertion. Anterior profile of snout and dorsal profile of head meeting in rounded obtuse angle near vertical immediately anterior to nares. Dorsal profile of head posterior to that line posterodorsally inclined and slightly con- vex. Predorsal profile of body slightly arched between supraoc- cipital spine and dorsal-fin origin. Dorsal profile of body straight to slightly concave between dorsal-fin origin and adi- pose fin and straight from adipose fin to dorsal procurrent rays. Ventral profile of head and body smoothly convex from margin of lower lip to pelvic-fin origin or with indistinct rounded ob- tuse angle delimiting anteroventral angle of dentary. Upper jaw longer than, and overhanging, lower jaw. Anterior surface of snout fleshy, with minute papillae over surface. Greatest concentration of papillae on upper lip, margin of up- per jaw, and in mouth on fleshy folds and plicae between inner and medial series of premaxillary teeth. Lower lip with thick, fleshy anterior region and with numerous papillae on dorsal surface of lip. Infraorbital series poorly developed compared to many Crea- grutus species, covering less than one-half of cheek. Ventral margin of third infraorbital distinctly separated from horizontal limb of preopercle. Posteroventral margins of infraorbitals 3 and 4 rounded, with indentation or concavity at their juncture. Curvature of posteroventral margin of third infraorbital ap- proximately concentric with margin of orbit. Posterior margins of third through fifth infraorbitals broadly separated from verti- cal limb of preopercle. Premaxillary dentition in three series: primary series undu- lating, with 5 rounded, unicuspidate to tricuspidate teeth, with anterior tooth slightly displaced anteromedially but without pronounced gap between first and second tooth of series; trian- gular cluster of 3 larger teeth, crowded together medially; and single tooth occurring lateral to third or fourth tooth of primary premaxillary row. Maxilla with 2 or 3, rarely 4, unicuspidate to tricuspidate teeth. Dentary teeth 6, anterior 3 teeth largest and tricuspidate, albeit with relatively small lateral cusps. Second dentary tooth slightly higher and wider than first tooth, more than twice as high and wide as third tooth. Fourth through sixth dentary teeth unicuspidate or with barely apparent lateral cusps; teeth becoming progressively shorter posteriorly. Unpaired fins relatively large compared with most Creagru- tus species. Dorsal-fin rays typically ii,7-8, ii,7 rare. Distal margin of dorsal fin nearly straight, with slight elongation of anterior rays. Dorsal-fin origin slightly posterior of vertical through pelvic-fin origin. Anal-fin rays ii,10-12 or iii,10—12. Distal margin of anal fin slightly concave, with anterior rays most elongate. Single, paired hooks present on 3 to 6 anterior branched anal-fin rays in mature males. Anal-fin hooks of ma- ture males restricted to posterolateral surface of main shaft and posterior secondary branch of each ray. Pectoral-fin rays i, 10-12. Tip of pectoral fin extending posteriorly almost to pel- vic-fin base. Pelvic-fin rays i,7. Tip of pelvic fin approaching or, especially in well-developed mature males, extending pos- teriorly to anal-fin origin. Distal portion of pelvic fin turned medially in some individuals, giving fin slightly cupped form. NUMBER 613 151 FIGURE 62.—Creagrutus melasma, holotype, MBUCV V-22198, 32.4 mm SL; Venezuela, Estado Guarico, Parque Nacional Guatopo, Rio Orituco, first bridge along road from Santa Teresa to Altagracia. Pelvic-fin hooks of mature males, when present, located on all but smallest, distal branches of all branched rays. Gill rakers 3-6 + 8-10. COLORATION IN LIFE.—Dorsal and anal fins with bright red markings anteriorly, and black centrally (see color plates in Ro- man, 1992:169, and Gery, 1977:393). Dorsal lobe of caudal fin red. Dorsal surface of eye with red patch overlying reflective guanine. Dark body pigmentation as in specimens preserved in alcohol other than for guanine partially masking anterior one- third of dark midlateral stripe (e.g., Weitzman et al., 1996, fig. 1). COLORATION IN ALCOHOL.—Dorsal surface of head with dark, shallow and deep chromatophores. Large, stellate, deep-lying chromatophores lining exterior surface of frontal, except in region of anterior fontanel. Shallow, dark chromato- phores present over most of dorsal surface of head; most con- centrated on snout and on ventral portion of upper lip, but not forming distinct crescent-shaped mark present in many conge- ners. Three patches of dark chromatophores extending posteri- orly from portion of main field immediately dorsal to anterior margin of orbit; one over each orbit and one along midline over fontanel. Band of scattered, dark chromatophores extending posteriorly from pigmentation on snout to anteroventral margin of orbit and then around ventral and posterior margins of orbit. Scattered, stellate, dark chromatophores overlying dorsal por- tions of infraorbitals and opercle. Dorsal portion of body with small, dark chromatophores concentrated on and below posterior portion of scales; these chromatophores forming overall dark reticulate pattern. Ante- rior one-half of predorsal surface of body with longitudinal concentration of large, stellate, dark chromatophores. Small dark chromatophores along dorsal-fin base. Humeral mark darkest immediately dorsal to lateral line. Overall form of mark vertically elongate with orientation ranging from vertical to somewhat posterodorsally oblique. Dark midlateral body stripe extending from pectoral girdle posteriorly to caudal-fin base. Body stripe diffuse anteriorly, most sharply defined along ven- tral margin and on posterior portion of body. Stripe expanded posteriorly into diffuse triangle extending slightly ventral to lateral line on caudal peduncle. Region of body between mid- lateral stripe and anal-fin base unpigmented or with series of very small dark chromatophores delineating myosepta. Dor- sally tapered concentrations of dark pigmentation located be- tween bundles of fin-ray musculature at anal-fin base. Small dark chromatophores on caudal-fin membranes; chro- matophore concentration greatest along central and outer branched rays and dorsal and ventral procurrent rays. Small dark chromatophores on anal-fin membranes mainly restricted to narrow bands along fin-ray margins. Slightly larger, darker chromatophores forming diffuse longitudinal band on distal one-third of anal fin; some specimens with greatly enlarged, dark chromatophores, giving appearance of dark spot on fin an- teriorly. Small dark chromatophores present across dorsal-fin membranes with large, very dark chromatophores concentrated in central portion of anterior one-half of fin, giving appearance of large dark spot (spot well-developed across observed size range; present in 14.8 mm SL juvenile, MBUCV V-21257). Pectoral fins with series of dark chromatophores associated with most rays; chromatophores most numerous laterally. Pel- vic fins hyaline. ECOLOGY.—Creagrutus melasma inhabits small, shallow, shady streams of the Andean piedmont where the water is usu- ally clear and the substrate ranges from sand to gravel (Taphorn, 1992:174). Diet of adults consists of small seeds, os- tracods, gastropods, and aquatic insects, especially chironomid larvae (Pearse, 1920:24, 25; Winemiller, pers. comm., 1997; in Taphorn, 1992:174). Spawning occurs for six to eight months, with individuals probably spawning two or more times per 152 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY spawning season (Winemiller, 1989:239; Winemiller, pers. comm., 1997). In Carlo Volcan in the Rio Apure system, three ripe females (23-26 mm SL) had 93-96 oocytes larger than 0.6 mm (Winemiller, pers. comm., 1997). The relatively low num- ber of oocytes may be correlated with apparent insemination of the female and the laying of fertilized eggs as reported by Baensch and Riehl (1993:270). COMMON NAME.—Venezuela, Rio Orinoco basin: "Sardina" (Roman, 1992:169), "Dientefrio Pintada" (Taphorn, 1992:173). DISTRIBUTION.—Creagrutus melasma occurs in the northern portions of Venezuela east of the Andes from the state of Tachira in the west to the state of Sucre in the east. The species also occurs in many upland tributaries of the Rio Orinoco basin and in the Rios Tuy and Neveri of the Caribbean versant (Fig- ure 59, stars). REMARKS.—Material herein referred to as Creagrutus melasma from Lago de Valencia and tributary rivers was iden- tified as C. beni by Eigenmann (1920:12; 1927:422). This iden- tification is puzzling in light of the distinctiveness of the new species relative to C. beni and given that Eigenmann (1911) de- scribed C. beni from a locality in the upper Rio Madeira basin in northeastern Bolivia, a considerable distance from Lago de Valencia of northern Venezuela. Creagrutus melasma and C. beni are readily distinguished by the number of vertebrae (typi- cally 34 or 35, 1 specimen out of 60 had 36 vertebrae, in C. melasma versus 37 to 39 in C. beni) and by the relative size of the infraorbital bones (poorly developed, with posteroventral margin of the series distinctly separated from both the horizon- tal and the vertical limbs of the preopercle in C. melasma com- pared to the well-developed third infraorbital with its ventral margin approaching, or often contacting, the horizontal limb of the preopercle in C. beni). MATERIAL EXAMINED.—1364 specimens (21,22.8-40.7). VENEZUELA. Anzoategui: Quebrada Las Minas, tributary of Rio Querecual (approximately 9°57TSI, 64°35'W), MBUCV V-15444,1. Apure: Cano Naporal, tributary of Rio Portuguesa, MCNG 10302, 19. Rio Capanaparo, approximately 5 km downstream from crossing of highway between San Fernando de Apure and Puerto Paez (7°02'N, 67°25/W), ANSP 165139, 1. Aragua: Rio Tuy basin, mouth of Rio Cagua, approximately 10 km from Guayas (approximately 10°16'N, 67°09'W), MBUCV V-21257, 56 (3, 34.2^0.7, paratypes of Creagrutus melasma; 2 specimens cleared and counterstained for cartilage and bone); CAS 79622, 10 (paratypes of Creagrutus melasma); USNM 326056, 10 (paratypes of Creagrutus melasma; 2 spec- imens cleared and counterstained for cartilage and bone). Rio Bue, at Maracay (10°15'N, 67°36'W), CAS 69297 (formerly IU 15133), 75. Lago de Valencia basin, Rio Limon, east of I.N.A. (Agricultural Research Institute), MBUCV V-3045, 6. Rio Pao, near La Candelaria (approximately 10°07'N, 67°14'W), MCNG 14201, 3. Bolivar: Caicara, MHNLS 7240, 2. Barinas: Cano at entrance to Bocono dam, MCNG 5271, 402; MCNG 5401, 9. Rio Bocono at dam site, MCNG 8877, 8. Rio Tucupido at Las Canoas, MCNG 5648, 12. Cano Musao, MCNG 6347, 2. Cano Las Maravillas, MCNG 11944, 4. Cano at Estero Chiguira, MCNG 6546, 2. Carabobo: Rio Guacara basin, Rio Vigirima, approximately 10 km NNW of Guacara (approximately 10°24'N 67°55'W), ANSP 134171, 48 (3, 33.5-34.2, paratypes of Creagrutus melasma). Rio Las Penitas at Vigirima, MCNG 24647, 4. Lago de Valencia basin, Vigir- ima, Rio Las Penitas (approximately 10°20'N 67°52'W), INHS 60021, 10 (3, 33.2-36.0, paratypes of Creagrutus melasma). Lago de Valencia, at Guataparo dike, W of Valencia, MHNLS 503, 6 (paratypes of Creagrutus melasma). Rio Manuare, ap- proximately 16 km along river from Manuare (09°59'N 67°45'10"W), MCNG 15354, 56 (paratypes of Creagrutus melasma). Cano La Camarca, N of San Diego (10°15'N, 67°57'W), MCNG 24622, 34 (paratypes of Creagrutus melasma). Lago de Valencia, Isla El Burro, CAS 69294 (for- merly IU 15134), 266. Lago de Valencia, Muelle Nuevo, oppo- site Isla El Burro, MHNLS 5882, 1. Lago de Valencia basin, Cano la Cumara, 3 km N of San Diego (10°16'33"N 67°56'13"W), INHS 60446, 35 (5, 32.2-35.0). Lago de Valen- cia, MBUCV V-uncataloged, 6. Rio Onoto, Puente Onoto, about 40 km from San Carlos (9°59'N, 68°22'W), MBUCV V-9919, 1. Rio Chirigu, tributary of Rio Pao, MCNG 15281, 5. Cano near Belen, MCNG 15295, 7. Cano Guamita, MCNG 15342, 60. Cojedas: Quebrada Camoruco, MCNG 6786, 2. Rio Chorreron, 10 km from Apartaderos (approximately 9°41/N, 68°56'W), MCNG 13780, 6. Rio Portuguesa basin, Rio Onoto, 2 km E of Apartaderos (approximately 9°41'N, 68°54'W), MHNLS 502, 7. Quebrada Guabinas, at highway from San Carlos to Acarigua, MHNLS 2502, 1. Rio Portuguesa basin, Rio Manrique, 2 km upstream of Manrique (approximately 9°49'N, 68°32'W), MHNLS 499, 6. Rio Portuguesa basin, Quebrada Tierra Caliente, 5 km W of Manrique, MHNLS 520, 10. Guarico: Parque Nacional Guatopo, Rio Orituco, first bridge along road from Santa Teresa to Altagracia (approxi- mately 9°59'N, 66°30'W), MBUCV V-22198, 1 (32.4, holo- type of Creagrutus melasma); MBUCV V-24020, 2 (32.0-33.9, paratypes of Creagrutus melasma). Miranda: At bridge near Araguita (10°13'N, 66°27'W), MCNG 14296, 3. Monagas: Rio Caripe, Sector Salle, on the Las Parcelas Road, 6 km from Carripito, MBUCV V-9753, 1. Rio Cocoyal, MCNG 16977, 3. Quebrada N of San Francisco de Maturin, MHNLS 517, 2. Rio Colorado at San Antonio de Maturin (10°07'N, 63°43'W), MHNLS 527,9. Rio Aragua, at road from Maturin to Quiriquire, approximately 10 km from Maturin (ap- proximately 9°58'N, 63°25'W), MHNLS 8064, 1. Rio Aragua, 10 km from Aragua de Maturin, at road from Maturin to Quiri- quire (9°58'N, 63°49'W), MHNLS 8879, 1. Distrito Acosta, Rio Caripe basin, Embalse El Guamo, MHNLS 9437, 16. Por- tuguesa: Cano La Lora, tributary of Rio Tucupido, MCNG 122, 1. Tributary of Rio Tucupido, MCNG 2443, 9. Rio Tucu- pido at dam site, MCNG 8835, 3. Rio Tucupido, Los Hierros (8°59'N, 69°53'W), MCNG 9215, 2. Rio Tucupido, Los Hier- ros, 7 km N of Tucupido (8°59'N, 69°53'W), MHNLS 6361, 2. Cano N of Tucupido, 6 km along road to Los Hierros, MHNLS NUMBER 613 153 2678, 6. Embalse Tucupido, MCNG 19638, 1; MCNG 19798, 6; MCNG 19303, 3. Cano, tributary of Rio Bocono, near dam, MCNG 10666, 6. Tributary of Rio Bocono, upstream from Pu- erto Paez, MCNG 703, 8. Cano at road from Chabasquen to Barquismeto, tributary of upper Rio Guanare, MCNG 124, 1. Cano Buchi, between Acarigua and Guanare, MCNG 10858,5. Rio Las Marias, bridge on Highway #5, MCNG 11261, 1. Rio Las Marias, MCNG 13314, 1; MCNG 19769, 1. Rio Are, at bridge on Highway 5 between km 227 and 228, MCNG 11616, 5. Cano Bombicito, near Aparicion (9°2A1i, 69°23'W), MCNG 11842,1. Cano Volcan, MCNG 15380, 14. Cano San Rafael, at km 247 on Highway 5, MCNG 16727, 1. Rio Saguas, MCNG 18737, 5. Sucre: Rio Neveri, at road to Turimiquire, near Cam- bural, MBUCV V-15419, 2. Rio Neveri, at road to Turimi- quire, near Paraparo, MBUCV V-15423, 3. Rio Neveri, near Paraparo, MBUCV V-15428, 4. Rio Neveri, Quebrada Carras- poso, MBUCV V-15405, 2. Rio Neveri, Los Morochos, MBUCV V-15447, 2. Cano Cruz de Agua, MBUCV V-15451, 3. Cano Juan Antonio, MCNG 17051, 1. Tdchira: Tributary of Rio Quinimari, MCNG 6484,4. Cano tributary to Rio Chururu, MCNG 6626, 3. Cano Toronduy, at bridge on San Cristobal road, MCNG 11661, 21. Rio San Agaton, MCNG 11790, 1. Yaracuy: Rio Cojedas basin, Quebrada Grande, between Nir- gua and Chivacoa, USNM 219615, 3 (22.8-36.3, paratypes of Creagrutus melasma); USNM 219616, 1 (31.8, paratype of Creagrutus melasma). Creagrutus menezesi, new species FIGURES 59,63,64, TABLE 35 DIAGNOSIS.—The combination of the possession of premax- illary dentition arranged in the three components generalized for most of the species of Creagrutus and Piabina without a distinctly larger gap between the first and second teeth of the primary series, 3 or 4 teeth on the maxilla, 6, rarely 7, teeth in the primary tooth row of the premaxilla, 5 or 6, rarely 4, den- tary teeth, 37 to 41 lateral line scales without a lamellar process over each pore, 8 to 11 predorsal median scales, 4 scale rows between the dorsal-fin origin and the lateral line, 36 to 38 ver- tebrae, 9 or 10 branched anal-fin rays, 2 post-anal median scales to the anal-fin origin, 6 gill rakers on the upper and 11 or 12 gill rakers on the lower limb of the first gill arch, the caudal peduncle depth (11.0%-12.9% of SL), the anal-fin length ( 1 7 . 7 % - 1 9 . 9 % of SL) , the postorbi ta l head length (35.1%-45.1% of HL), the bony orbital diameter (36.8%- 41.8% of HL), the interorbital width (27.4%-34.7% of HL), the relatively well-developed third infraorbital approaching, but not contacting, the horizontal limb of the preopercle, the lack of a series of dark midlateral spots on the body, the distinctly vertically elongate, ventrally tapering humeral mark extending ventral of the lateral line, and the absence of a discrete patch of dark pigmentation on the middle portion of the anterior dorsal- fin rays distinguishes Creagrutus menezesi within the clade composed of Creagrutus and Piabina. DESCRIPTION.—Morphometric and meristic data for Crea- grutus menezesi in Table 35. Head and body moderately robust. Greatest body depth at, to slightly anterior of, dorsal-fin origin. Dorsal profile of head convex from margin of upper lip to ver- tical through anterior margin of orbit, straight from that point to tip of supraoccipital spine in smaller specimens, slightly con- vex in that region in larger individuals. Interorbital region transversely convex. Predorsal profile of body slightly convex across size range of examined specimens, without change in alignment relative to dorsal profile of head. Dorsal surface of body with median ridge proximate to dorsal-fin origin, ridge more obvious in largest examined specimens. Ventral profile of head with obtuse angle at anteroventral corner of dentary, gen- tly convex from that point to isthmus. Profile of prepelvic re- gion of body slightly convex at all sizes. Prepelvic region of larger specimens obtusely flattened transversely. Head obtusely pointed in lateral view and more laterally compressed and pointed in dorsal view. Upper jaw longer than, and distinctly overhanging, lower jaw. Snout slightly fleshy an- teromedially, with few scattered papillae above margin of up- per lip. Upper lip along with plicae and folds extending be- tween outer and medial premaxillary teeth covered with concentrations of papillae. Lower lip fleshy anteriorly, with pa- pillae concentrated on dorsal margin of lip and immediately proximate portions of anterior and lateral margins of lip. Infraorbital series relatively well developed. Third infraor- bital approaching but not contacting horizontal limb of preo- percle. Posterior margins of third and fourth infraorbitals fall- ing slightly short of vertical limb of preopercle. Premaxillary dentition in three series: primary row curved overall, somewhat sigmoid in larger specimens, consisting of 6, rarely 7, teeth, without pronounced gap between first and sec- ond tooth of series but with medial tooth well separated from anterior tooth of contralateral series; triangular cluster of 3 larger teeth; and single tooth of form similar to that of primary series occurring lateral to fourth tooth of primary premaxillary row, or occasionally slightly more anterior of that position. Maxilla with 3 teeth in smaller specimens, with largest exam- ined individuals having 3 or 4 teeth. Teeth shifting ontogeneti- cally from unicuspidate in small specimens, to bicuspidate in medium-sized individuals, to tricuspidate in large specimens. Small specimens with 6 dentary teeth. First through third den- tary teeth in juveniles distinctly larger, with first and second teeth subequal and approximately 1.5 times height of third tooth. First and second teeth tricuspidate with middle cusp well developed, second tooth bicuspidate with anterior cusp dis- tinctly larger. Fourth through sixth teeth unicuspidate with pos- teriorly recurved tip. Larger specimens with 5, rarely 4, dentary teeth. Tricuspidate first and second dentary teeth of larger indi- viduals distinctly larger than other teeth in series, with second tooth larger both vertically and especially horizontally than first tooth; tricuspidate third tooth approximately one-half height of fourth tooth; fourth and fifth teeth (when latter 154 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY TABLE 35.—Morphometrics and meristics of Creagrutus menezesi. new species: (A) holotype of C. menezesi, MZUSP 50544; (B) paratypes of C. menezesi (n=63), and (C) samples of C. menezesi from Rio Branco basin (n= 13). Standard length is expressed in mm; measurements 1 to 14=percentages of standard length; 15 to 18=per- centages of head length. Characters Standard length 1. Snout to anal-fin origin 2. Snout to pelvic-fin insertion 3. Snout to pectoral-fin insertion 4. Snout to dorsal-fin origin 5. Dorsal-fin origin to hypural joint 6. Dorsal-fm origin to anal-fin origin 7. Dorsal-fin origin to pelvic-fin insertion 8. Dorsal-fin origin to pectoral-fin insertion 9. Caudal peduncle depth 10. Pectoral-fin length 11. Pelvic-fin length 12. Dorsal-fin length 13. Anal-fin length 14. Head length 15. Postorbital head length 16. Snout length 17. Bony orbital diameter 18. Interorbital width Lateral line scales Scale rows between dorsal-fin origin and lateral line Scale rows between anal-fin origin and lateral line Predorsal median scales Branched dorsal-fin rays Branched anal-fin rays Branched pelvic-fin rays Pectoral-fin rays Vertebrae A 58.7 63.4 47.7 24.1 46.8 57.9 33.8 29.5 33.6 12.6 19.8 15.3 21.8 18.7 26.0 44.9 29.9 38.1 32.6 39 4 3 9 8 10 7 13 37 B Morphometrics 32.0-64.3 62.9-68.3 44.2-49.3 23.2-27.1 45.2-49.9 54.8-59.7 31.4-35.0 27.5-33.1 31.8-35.5 11.5-12.9 18.7-21.3 14.8-17.8 20.2-23.0 17.7-19.9 25.2-27.9 39.1-45.1 27.4-33.1 36.9-39.6 29.4-34.7 Meristics 38-41 4 3 9-11 8 9-10 6-7 13-15 36-38 C 27.2-51.2 61.9-66.9 45.5-50.9 24.1-27.2 44.9-48.5 53.6-57.7 29.4-33.2 26.3-27.9 30.0-32.8 11.0-12.1 18.6-21.6 14.0-17.1 20.1-25.0 17.7-19.5 25.2-28.4 35.1-42.6 24.3-31.0 36.8-41.8 27.4-30.5 37-41' 4 3 8-10 8 9-10 6-7 12-14 37-38 'Forty-one lateral line scales present in only 1 of 13 specimens from Rio Branco. present) distinctly smaller than third toothwith fourth tooth uni- cuspidate or weakly tricuspidate and fifth tooth unicuspidate. Dorsal-fin rays ii,8 in all specimens. Dorsal-fin origin slightly anterior of vertical through pelvic-fin insertion. Profile of distal margin of dorsal fin slightly concave. Anal-fin rays ii,9-10. Profile of distal margin of anal fin concave, more so in largest examined specimens in which anterior branched rays form moderate lobe. Mature males with hooks present on first and second branched anal-fin rays. Pectoral-fin rays i, 11-14. Tip of pectoral fin extending posteriorly slightly less than two- thirds of distance to pelvic-fin insertion. Pelvic-fin rays typi- cally i,6,i; sometimes i,7 in larger specimens. Tip of pelvic fin extending posteriorly to anus in smaller specimens, falling slightly short of that point in larger individuals. Mature males with hooks present on all branched anal-fin rays. Gill rakers 6+11-12. COLORATION IN ALCOHOL.—Overall coloration of majority of specimens ranging from quite pale to light tan. Dark pig- mentation on specimens very subtle and often not readily ap- parent unless examined microscopically. Smaller specimens with dorsal surface of head lacking surface pigmentation, or with few scattered chromatophores in region posterior of snout. Dark, surface chromatophores on posterior portion of head more concentrated, but still relatively sparse, in larger individ- uals. Field of dark, relatively evenly spaced, deep-lying chro- matophores located over surface of posterior portion of brain, with two longitudinally elongate contralateral patches of chro- matophores positioned over anterior portion of brain; pigmen- tation quite dense in many larger specimens. Dark chromato- phores scattered over snout. Region immediately anterior to nostrils typically with distinct crescent-shaped patch of chro- matophores; patch not obvious in largest specimens examined. Region anteroventral of orbit with diffuse, dark chromato- phores forming narrow, posteroventrally angled stripe; stripe not continuous anterodorsally with patch of pigmentation ante- rior to nostrils. Irregular series of chromatophores along poster- oventral margin of orbit. Scattered chromatophores over dorsal portions of infraorbitals and opercle. Scales of dorsal surface of body with scattered chromato- phores along margins and diffuse patch of chromatophores NUMBER 613 155 FIGURE 63.—Creagrutus menezesi, new species, holotype, MZUSP 50544, 58.7 mm SL; Brazil, Goias, Rio Tocantins basin, Ribeirao Paranoa do Meio, at road crossing 11 air km NNE of Formosa (approximately 15°25'S, 47°18'W). FIGURE 64.—Creagrutus menezesi, new species, nontype specimen, MZUSP 29892, 28.3 mm SL; Brazil, Roraima, Rio Branco, beach of Rio Xeriuini (approximately l°0'S, 61°50'W). over center of exposed portion of scale; pattern most distinct anteriorly on dorsolateral portion of body. Diffuse pattern of scattered chromatophores covering much of lateral surface of body in smaller specimens, these chromatophores slightly more concentrated midlaterally on caudal peduncle, but not forming discrete horizontal stripe. Diffuse lateral chromatophore field terminating anteriorly approximately two scales posterior of humeral mark resulting in intervening hyaline region. Region anterior to humeral mark in smaller specimens typically hya- line as a consequence of lack of dispersed chromatophores, but with some scattered chromatophores in that region in larger in- dividuals. Humeral mark present, but relatively faint compared to condition in many congeners, albeit with pigmentation in mark more concentrated than scattered chromatophores present on lateral surface of body. Concentration of chromatophores more noticeable on dorsal portion of mark in some individuals. Mark vertically elongate, slightly ventrally tapering, and ex- tending ventrally nearly to horizontal through pectoral-fin in- sertion. Orientation of mark somewhat variable around vertical line (Figures 63, 64). Smaller specimens with mark continuing dorsally to horizontal through dorsal margin of orbit; mark ex- tending somewhat more dorsally in larger individuals. Dorsal portion of mark with slight anterior extension. Midlateral sur- face of body with very diffuse dusky band in specimens of most sizes; band anteriorly attenuate and less intense, not reaching to rear of humeral mark. Surface portion of band formed of dispersed, dark chromatophores that overlie nar- rower, deeper, and more intense region of pigmentation form- ing most of longitudinal band. Deep-lying, dark pigmentation irregularly dispersed in smaller specimens, with localized areas more intensely pigmented, particularly along myosepta. Dorsal fin with distal portion of second unbranched ray cov- ered with dark chromatophores. Distal portions of membranes of anterior 4 or 5 branched dorsal-fin rays with scattered chro- matophores that form diffuse spot. Anal fin with scattered chromatophores along bases of anterior branched rays. Caudal- fin rays variably outlined by dark chromatophores, those along middle caudal-fin rays forming faint stripe in many specimens; chromatophores on middle caudal-fin rays more concentrated basally in some smaller individuals. Basal portions of rays of mid portions of upper and lower lobes of caudal fin variably 156 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY outlined by dark chromatophores. Pectoral and pelvic fins hya- line. ETYMOLOGY.—The specific name, menezesi, is in honor of Naercio A. Menezes, Museu de Zoologia, Universidade de Sao Paulo, Brazil, in recognition of his myriad contributions to our knowledge of South American fishes and all his assistance to the senior author through the years. ECOLOGY.—Stomach contents of two specimens prepared for clearing and counter staining consisted of chopped up seeds and insect parts. Creagrutus menezesi has been captured within the upper Rio Tocantins basin sympatrically with C. atrisignum in the Rio Maranhao and with C. saxatilis and C. figueiredoi in residual pools in the channel of the Rio Tocantins formed during filling of the Serra da Mesa Reservoir. In the upper Rio Araguaia at Barra do Garcas, Mato Grosso, Brazil, C. menezesi was col- lected jointly with C. seductus and C. figueiredoi. DISTRIBUTION.—Creagrutus menezesi is widespread in the Rio Tocantins basin and is tentatively considered to occur in the Rio Branco basin and the Rio Negro near the mouth of the Rio Branco (Figure 59, diamonds; see "Remarks," below, with respect to localities outside the Rio Tocantins). COMPARISONS.—Creagrutus menezesi can be readily distin- guished from the other members of the genus known from the Rio Tocantins and Rio Negro basins by a combination of de- tails of dentition and meristic characteristics (see keys to the species in each basin, above). REMARKS.—The above description is based on the holotype and paratype series of Creagrutus menezesi that originated in the upper portions of the Rio Tocantins, a region from which an extensive series of specimens is available (see "Material Exam- ined," below, and Figure 59). Although we have only two spec- imens of Creagrutus menezesi from the other major branch of the Rio Tocantins system, the Rio Araguaia (USNM 342234, USNM 342236), this population sample agrees with the upper Rio Tocantins samples in all examined features. Various lots of smaller specimens in poor condition, but apparently conspe- cific with C. menezesi, originated in the lower portions of the Rio Tocantins basin. Several lots of C. menezesi, including lots of both small specimens and larger specimens in somewhat poor condition, from the Rio Branco and from portions of the Rio Negro ad- joining the confluence of the Branco with the Negro (Figure 59, locality labeled 6) also are apparently conspecific with C. menezesi. This is surprising, given the usual limited geographic distribution of most Creagrutus species. The population sam- ples originating in the Rio Tocantins and Rio Branco basins agree in meristic features (Table 35), although they have a modal shift in vertebral numbers. The Rio Tocantins population has 36 to 38 vertebrae with a strong mode of 37 (36, 27 speci- mens; 37, 119 specimens, 38, 19 specimens), whereas the Rio Branco and Rio Negro samples have equal numbers of speci- mens with 37 and 38 vertebrae (15 specimens apiece). The ranges of several proportional values in the Rio To- cantins samples (dorsal-fin origin to pelvic-fin insertion, dor- sal-fin origin to pectoral-fin insertion, and postorbital head length), although overlapping to a degree with those of speci- mens from the Rios Branco and Negro, are shifted modal ly compared with the samples from those basins (see Table 35). The samples from the Rio Branco and Rio Negro systems, however, have either significantly smaller body size than those from the Rio Tocantins or are of relatively comparable body size but are somewhat twisted, making comparisons difficult. The Rio Branco samples are, furthermore, not as well pre- served as the bulk of the material from the upper Rio Tocantins, making direct comparisons problematic. Additional samples from the Rio Branco and Rio Negro basins are necessary to clarify the significance of these modal differences between populations, and until that time we tentatively assign the exam- ined lots from those basins to C. menezesi. MATERIAL EXAMINED.—634 specimens (64,23.1-75.2). H O L O T Y P E . — B R A Z I L . Goias: Rio Tocantins basin, Ribeirao Paranoa do Meio, at road crossing 11 air km NNE of Formosa (approximately 15°25'S, 47°18'W), collected by W.C. Starnes et al., 13 Nov 1984, MZUSP 50544, 1 (58.7). PARATYPES.—63 specimens (63,32.0-75.2). BRAZIL. Goids: Rio Tocantins basin, Ribeirao Paranoa do Meio, at road crossing 11 air km NNE of Formosa (approxi- mately 15°25'S, 47°18'W), collected with holotype, MZUSP 50545, 8 (36.5^6.5); USNM 292229, 11 (32.0-64.2; 2 speci- mens cleared and counterstained for cartilage and bone). Mi- nacu, Cavalcante, Rio Tocantins in Serra da Mesa (13°50'S, 48°19'W), collected by G.W. Nunan and D.F. Moraes, Jr., 20 Oct 1985, MNRJ 12614, 8 (36.1-55.9). Minacu/Colinas do Sul, Rio Tocantins, in large pools below Usina Hidroelectrica Serra da Mesa during filling of reservoir, collected by D.F. Mo- raes et al., 28 Oct to 3 Nov 1996, MNRJ 17338,11 (48.8-71.2); USNM 350456, 10 (56.0-75.2; formerly MNRJ 16566, in part); MNRJ 17333, 10 (55.3-69.3); USNM 350456, 5 (61.2-73.7; formerly MNRJ 16562, in part). NONTYPE SPECIMENS.—570 specimens (18,23.1-74.0). BRAZIL. Para: Rio Itacaiunas, Caldeirao (5°45 'S , 50°30'W), MZUSP 30576, 25. Maranhao: Rio Tocantins, Es- treito (approximately 6°32'S, 47°27'W), MZUSP 4970, 57 (5, 23.1-25.7; 2 specimens cleared and counterstained for cartilage and bone). Rio Tocantins at Carolina (7°20'S, 47°28'W), CAS 69243, 6. Tocantins: Rio Tocantins at Porto Nacional (10°42'S, 48°25'W), CAS 69258, 1. Goias: small "brook" into Rio Mara- nhao at Mosondo, CAS 69262,2. Ribeirao Tacaural, tributary of Rio dal Almas, CAS 69242, 10. Minacu, Cavalcante, Rio To- cantins in Serra da Mesa (13°5O'S, 48°19'W), MNRJ 13343, 5. Minacu, Cavalcante, Rio Tocantins, MNRJ 13049, 39. Campi- nacu, Niquelandia, Rio Maranhao, at Porto Alfredinho (14°04'S, 48°30'W), MNRJ 12558, 7. Campinacu, Rio Boa Nova, left bank tributary of Rio Tocantins (13°52'S, 48°2rW), MNRJ 12576, 1. Niquelandia, Rio Maranhao, at Estreito, near mouth of Rio Bagagem (13°59'S, 48°22'W), MNRJ 12741, 7. NUMBER 613 157 Niquelandia, Rio Maranhao, 20 km above confluence with Rio Bagagem, near mouth of Rio Arara (14°00'S, 48°26'W), MCP 15886, 12. Uruacu, Rio Maranhao, along road between Niquelandia and Uruacu (14°31'S, 49°03'W), MCP 15852, 11. Minacu/Colinas do Sul, Rio Tocantins, in large pools below Usina Hidroelectrica Serra da Mesa during filling of reservoir, USNM 350451 (formerly MNRJ 16566, in part), 10; USNM 350454 (formerly MNRJ 16562, in part), 5; MNRJ 16567, 6; USNM 350455 (formerly MNRJ 16567, in part), 20. Minacu/ Colinas do Sul, Rio Tocantins, in large pools formed by a riacho on left bank of Rio Tocantins during filling of Usina Hidroelec- trica Serra da Mesa reservoir, MNRJ 16563, 9; MNRJ (ex 16564) 3; USNM 350453 (formerly MNRJ 16564, in part) 16. Mato Grosso: Upper Rio Araguaia basin, Municipio de Barra do Garcas, Corrego Fundo (approximately 15°53'S, 52°15'W), USNM 342236, 1 (74.0, formerly ICLMA 190, in part); USNM 342234, 1 (formerly ICLMA uncataloged, in part). The following specimens from the Rio Negro and Rio Branco basins are tentatively assigned to Creagmtus menezesi: BRAZIL. Roraima: Rio Branco, beach of Rio Xeriuini (ap- proximately l°0 'S, 61°50'W), MZUSP 29892, 311 (10, 27.2-29.4). Rio Branco system, Rio Surumu (approximately 3°22/N, 60°19'W), MZUSP 16512, 2 (1, 51.2; other specimen twisted and only proportional head measurements and meristic data taken). Rio Branco, Boa Vista, MZUSP 17714, l.Amazo- nas: W of Moura, near junction of Rio Negro and Rio Branco (l°30'S, 61°48'W), ANSP 135566, 1 (29.9); ANSP 146130, 1. Creagmtus meridionalis, new species FIGURES 59,65, TABLE 36 DIAGNOSIS.—The combination of the possession of premax- illary dentition arranged in the three components generalized for most of the species of Creagrutus and Piabina without a distinctly larger gap between the first and second teeth of the primary series, 2 or 3 teeth on the maxilla, 6, much less com- monly 5, teeth in the primary tooth row of the premaxilla, 4 or 5 dentary teeth, 38 to 41 lateral line scales without a lamellar process over each pore, 9 to 11 predorsal median scales, 4 scale rows between the dorsal-fin origin and the lateral line, 37 to 39 vertebrae, 11 to 13 branched anal-fin rays, 2 post-anal median scales to the anal-fin origin, 6 to 8 gill rakers on the upper limb and 9 or 10 gill rakers on the lower limb of the first gill arch, the distance from the snout to the dorsal-fin origin (45.5%-49.8% of SL), the distance from the snout to the anal- fin origin (62.1%-66.4% of SL), the distance from the dorsal- fin origin to the pectoral-fin insertion (31.0%-34.8% of SL), the caudal-peduncle depth (10.5%-12.2% of SL), the dorsal-fin length (20.2%-24.0% of SL), the bony orbital diameter (32.0%-36.0% of HL), the postorbital head length (39.3% -44.5% of HL), the snout length (28.0%-31.1% of SL), the in- terorbital width (30.6%—34.4% of HL), the moderately devel- oped third infraorbital with its ventral margin falling distinctly short of the horizontal limb of preopercle, the lack of a series of TABLE 36.—Morphometrics and meristics of Creagrutus meridionalis. new species: (A) holotype of C. meridionalis, new species, MZUSP 50546; and (B) paratypes of C. meridionalis (n=63). Standard length is expressed in mm; mea- surements 1 to 14=percentages of standard length; 15 to 18=percentages of head length. Characters Standard length 1. Snout to anal-fin origin 2. Snout to pelvic-fin insertion 3. Snout to pectoral-fin insertion 4. Snout to dorsal-fin origin 5. Dorsal-fin origin to hypural joint 6. Dorsal-fm origin to anal-fin origin 7. Dorsal-fin origin to pelvic-fin insertion 8. Dorsal-fin origin to pectoral-fin insertion 9. Caudal peduncle depth 10. Pectoral-fin length 11. Pelvic-fin length 12. Dorsal-fin length 13. Anal-fin length 14. Head length 15. Postorbital head length 16. Snout length 17. Bony orbital diameter 18. Interorbital width Lateral line scales Scale rows between dorsal-fm origin and lateral line Scale rows between anal-fin origin and lateral line Predorsal median scales Branched dorsal-fin rays Branched anal-fin rays Branched pelvic-fin rays Pectoral-fin rays Vertebrae A B Morphometrics 59.9 64.1 47.7 23.7 48.4 56.4 34.1 30.0 34.2 12.0 20.0 15.4 21.7 17.4 25.7 44.2 30.5 33.1 33.1 19.9-62.0 62.1-66.4 46.4-50.5 23.1-25.0 45.5-49.8 55.8-59.8 29.3-34.8 25.1-29.8 31.0-34.8 10.5-12.2 18.0-20.7 14.5-17.4 20.2-24.0 16.6-18.9 24.7-26.8 39.3-44.5 28.0-31.1 32.0-36.0 30.6-34.4 Meristics 39 4 3 10 8 12 6 14 38 38-41 4 3 9-11 8 11-13 6 12-14 37-39 dark midlateral spots on the body, the vertically elongate, ven- tral ly attenuating humeral mark, the absence of a spot of dark pigmentation on the basal portion of the middle caudal-fin rays, and the absence of a discrete patch of dark pigmentation on the middle portion of the anterior dorsal-fin rays distinguishes Cre- agrutus meridionalis within the clade composed of Creagrutus and Piabina. DESCRIPTION.—Morphometric and meristic data for Crea- grutus meridionalis in Table 36. Examined juveniles (approxi- mately 20-30 mm SL) relatively elongate; specimens larger than 40 mm SL becoming increasingly deep-bodied, with rela- tive body depth greatest in larger specimens. Greatest body depth at vertical through dorsal-fin origin in smaller individu- als; located at, or somewhat anterior of, that point in larger specimens. Dorsal profile of head distinctly convex from mar- gin of upper lip to region of vertical through posterior margin of orbit, straight from that point to rear of supraoccipital spine. Dorsal surface of head medially flattened transversely, more so posterior to vertical through center of orbit. Predorsal profile of body smoothly continuous with that of head and very slightly convex in smaller specimens, with notable change in alignment 158 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY relative to profile of head and convexity distinctly more pro- nounced in larger specimens. Dorsal profile of body poster- oventrally angled along dorsal-fin base; straight from that point to caudal peduncle in smaller specimens, somewhat convex in larger specimens. Ventral profile of head with rounded obtuse angle delimiting anteroventral angle of dentary, angle typically more obvious in larger specimens. Profile of head and body gently convex from anteroventral corner of dentary to anal-fin origin in smaller specimens; convexity more pronounced in larger individuals. Prepelvic region of body somewhat flat- tened transversely in larger specimens. Head obtusely pointed in lateral view, more pointed in dorsal view. Upper jaw longer than, and overhanging, lower jaw. An- terior portion of snout fleshy, more so in larger individuals, with numerous papillae scattered over anterior surface, across upper lip, and on plicae and folds extending between outer and medial premaxillary teeth. Lower lip fleshy anteriorly, with nu- merous papillae over lip. Infraorbital series moderately developed. Ventral margin of third infraorbital distinctly curved, with ventralmost portion falling somewhat short of horizontal limb of preopercle even in larger examined specimens. Posterior margins of third through fifth infraorbitals falling distinctly short of vertical limb of pre- opercle, gap gradually diminishing dorsally. Premaxillary dentition in three series: primary row slightly curved, typically with 6 teeth, but with 5 teeth present on one or both premaxillae in a few specimens, without pronounced gap between first and second tooth of series but with medial teeth of contralateral series distinctly separated; triangular clus- ter of 3 larger teeth with posterolateral tooth of cluster largest; and single tooth of form similar to that of primary series lying lateral to region of contact of fourth or fifth teeth of primary premaxillary series. Maxilla with 2 or 3 triscupidate teeth. Den- tary with 4 or 5 teeth. First and second teeth subequal or second slightly larger; both teeth tricuspidate with middle cusp largest. Third tooth approximately one-half size of preceding teeth, bi- cuspidate with first cusp distinctly larger. Fourth and fifth teeth (when latter present) compressed and tricuspidate. Dorsal-fin rays ii,8. Dorsal-fin origin at, or slightly anterior of, vertical through pelvic-fin insertion. Profile of distal margin of dorsal fin slightly concave. Anal-fin rays ii,l 1-13. Profile of distal margin of anal fin distinctly concave, with last un- branched and anterior two branched rays forming distinct lobe. Hooks typically present on anal-fin rays in mature males of many Creagrutus species not found in examined specimens. Pectoral-fin rays i, 11-13. Tip of pectoral fin extending posteri- orly two-thirds to three-fourths of distance to pelvic-fin inser- tion. Pelvic-fin rays i,6,i. Hooks typically present on pelvic-fin rays in mature males of many Creagrutus species not found in examined specimens. Tip of pelvic fin extending posteriorly to point somewhat short of anus. Gill rakers 6-8+ 9-10. COLORATION IN ALCOHOL.—Dorsal surface of head in smaller specimens with large, stellate, dark chromatophores on membranes overlying brain, and with scattered, dark, smaller surface chromatophores; deep-lying chromatophores in adults obscured by denser field of surface chromatophores, connec- tive- tissue layers, and thick bones. Field of small, dark chro- matophores on dorsal surface of head continuing anteriorly across snout to anterior of nares. Pigmentation anterior to nares more concentrated and forming dark crescent-shaped mark. Chromatophore field continuing in medium-sized individuals around ventral and posterior margins of orbit. Pigmentation at posterior margin of orbit continuous with broader pigmentation field on infraorbitals posterior to orbit and on dorsal one-half of opercle in larger specimens. Scales of dorsal surface of body covered with scattered, dark, small chromatophores, these more concentrated along posterior portions of scales, forming faint reticulate pattern. Obscure midlateral band formed by deep-lying chromatophores; band overlain by guanine in available specimens. Humeral mark ver- tically elongate in specimens of all sizes, relatively more devel- oped in larger specimens. Mark becoming attenuate ventrally, barely extending ventrally as far as lateral line in smaller speci- mens, extending approximately 1 scale ventral of lateral line in largest available individuals. Posterior margin of humeral mark typically nearly straight; anterior margin often with distinct concavity in its dorsal portion. Dorsal fin with scattered, dark chromatophores, more so on distal portions of anterior fin membranes. Basal portions of an- terior anal-fin rays outlined by dark chromatophores, with in- creased concentration of chromatophores on membranes of dis- tal one-half of anterior lobe of fin. Caudal fin with scattered chromatophores on rays and membranes, but without distinct pigmentation pattern. Pectoral and pelvic fins ranging from un- pigmented to pale with scattered, dark chromatophores on membranes. ETYMOLOGY.—The specific name, meridionalis, from the Latin for southern, refers to the distribution of the species in the southern portions of the range of Creagrutus. ECOLOGY.—The type locality of Creagrutus meridionalis is a small, clear stream. A single specimen prepared for clearing and staining in this study had stomach contents consisting of adult and larval insects. DISTRIBUTION.—Creagrutus meridionalis is known from the upper portion of the Rio Paraguai basin, Mato Grosso, Brazil, and eastern tributaries to Rio Paraguay in Paraguay (Figure 59, triangles). COMPARISONS.—In addition to Creagrutus meridionalis, only one other Creagrutus species, C. paraguayensis, is known from the Rio Paraguay basin. The two species differ in the number of branched anal-fin rays (11 to 13 in C. meridionalis versus 13 to 15 in C. paraguayensis) and in the number of scale rows between the lateral line and the dorsal-fin origin (4 versus 5, respectively). REMARKS.—Mahnert and G6ry (1988:8), in their paper de- scribing Creagrutus paraguayensis, reported one specimen collected in Paraguay as Creagrutus sp. (aff. paraguayensis). They noted that the single specimen available to them, col- lected in the province of Cordillera, Paraguay, differed from C paraguayensis in various meristic and morphometric details. NUMBER 613 159 FIGURE 65.—Creagrutus meridionalis, new species, holotype, MZUSP 50546, 59.9 mm SL; Brazil, Mato Grosso, Municipio de Jangada, Ribeirao Chiqueirao (tributary of Rio Jangada that, in turn, drains into the Rio Cuiaba), approximately 21 km W of Jangada (Jangada is at 15°14'S, 56°29'W). We have not examined this specimen, which was found within the geographic range of C. paraguayensis but outside the known distribution of C. meridionalis. The specimen of Crea- grutus sp. (aff. paraguayensis) was reported by Mahnert and Gery to have 4 scales above the lateral line, a count that is found in C. meridionalis but that contrasts with the 5 scales above the lateral line in C. paraguayensis, the only other mem- ber of the genus known from the Rio Paraguay basin. The rela- tive length from the snout to the pelvic-fin insertion cited by Mahnert and Gery for their specimen (1.6 times in SL = 62.5% of SL) falls within the range for that value for C. meridionalis (62.1%-66.4% of SL) but falls outside that for C. paraguayen- sis (55.3%-61.0% of SL). Mahnert and Gery's specimen has, however, a somewhat different overall appearance (compare Mahnert and Gery, 1988, figs. 6, 7 with Figure 65 herein), par- ticularly in the anterior portions of the head; thus, we only ten- tatively identify it as an individual of C. meridionalis. If addi- tional specimens reveal this population to be conspecific with C. meridionalis, then the range of C. meridionalis extends ap- proximately 200 km further south in the Rio Paraguay basin and overlaps the known distribution of C. paraguayensis, con- trary to the apparent allopatry of the two species based on spec- imens examined in this study. MATERIAL EXAMINED.—143 specimens (73,21.5-62.0). HOLOTYPE.—BRAZIL. Mato Grosso: Ribeirao Chiqueirao (tributary of Rio Jangada that, in turn, drains into the Rio Cuiaba), approximately 21 km W of Jangada (latter locality at 15°14'S, 56°29'W) on road to Barra do Bugres, Municipio de Jangada; collected by R.E. Reis et al., 10 Aug 1991, MZUSP 50546, 1 (59.9). PARATYPES.—71 specimens (63, 19.9-62.0). BRAZIL. Mato Grosso: Ribeirao Chiqueirao (tributary of Rio Jangada, which, in turn, drains into the Rio Cuiaba), ap- proximately 21 km W of Jangada (latter locality at 15°14'S, 56°29'W) on road to Barra do Bugres, Municipio de Jangada, collected with holotype, MZUSP 50547, 12 (23.1-62.0; 1 spec- imen cleared and counterstained for cartilage and bone); MCP 18738, 13 (21.5-61.9); USNM 341363, 12 (24.7-61.7; 2 speci- mens cleared and counterstained for cartilage and bone); FML 2527, 1 (52.0). PARAGUAY. Amambay. Rio Apa, 400 m below bridge to Bella Vista, Rio Paraguay basin (22°07'15"S, 56°31'15"W), collected by A. Silfvergrip et al., 14 Jun 1994, NRM 22619, 20 (28.3^5.6); MNHNP 2999, 13 (5, 19.9-44.7). NONTYPE SPECIMENS.—71 specimens (9,43.2-54.5). PARAGUAY. Amambay: Rio Aquidaban in Parque Nacional Cerro Cora, approximately 32 km WSW of Pedro Juan Cabal- lero, Rio Paraguay drainage (22°38'12"S, 56°03'W), UMMZ 206757, 33. Arroyo Aquidaban-Niqui at monument site and slightly upstream in Parque Nacional Cerro Cora (22°38'S, 56°11'W), NRM 15966, 13 (2, 43.2^5.0). Concepcion: Ar- royo Guaireno, at bridge on dirt highway, 33 km S of junction with highway 5, at Yby-Yau, tributary to Rio Ypane of Rio Par- aguay drainage (23°15'18"S, 56°30'00"W), UMMZ 208001, 25(7,51.0-54.5). Creagrutus molinus, new species FIGURES 66,67, TABLE 37 DIAGNOSIS.—The elongate form of the head and body and, in particular, the unusual premaxillary dentition with only two of the three principal components of the premaxillary dentition generalized for the species of Creagrutus, the primary tooth row without a pronounced gap between the first and second teeth, and the posteromedial triangular cluster of three teeth, combined with the absence of the third component, the separate tooth lateral to the fourth tooth in the primary premaxillary tooth row distinguishes Creagrutus molinus from all other spe- cies in the clade consisting of Creagrutus and Piabina. In addi- tion, the combination of the contact of the first and second teeth of the primary premaxillary series, 3 teeth on the maxilla, 6 teeth in the primary tooth row of the premaxilla, 41 lateral 160 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY TABLE 37.—Morphometrics and meristics of holotype of Creagrutus molinus, new species, MZUSP 41461. Standard length is expressed in mm; measure- ments 1 to 14=percentages of standard length; 15 to 18=percentages of head length. Characters Standard length 1. Snout to anal-fin origin 2. Snout to pelvic-fin insertion 3. Snout to pectoral-fin insertion 4. Snout to dorsal-fin origin 5. Dorsal-fin origin to hypural joint 6. Dorsal-fin origin to anal-fin origin 7. Dorsal-fin origin to pelvic-fin insertion 8. Dorsal-fin origin to pectoral-fin insertion 9. Caudal peduncle depth 10. Pectoral-fin length 11. Pelvic-fin length 12. Dorsal-fin length 13. Anal-fin length 14. Head length 15. Postorbital head length 16. Snout length 17. Bony orbital diameter 18. Interorbital width Lateral line scales Scale rows between dorsal-fin origin and lateral line Scale rows between anal-fin origin and lateral line Predorsal median scales Branched dorsal-fin rays Branched anal-fin rays Branched pelvic-fin rays Pectoral-fin rays Vertebrae Morphometrics 55.8 63.4 44.8 24.7 45.3 53.8 26.0 21.5 27.8 11.3 18.6 13.1 19.7 18.6 25.1 39.3 31.0 33.6 30.7 Meristics 41 4 3 11 8 12 6 12 38 line scales without a lamellar process over each pore, 11 pre- dorsal median scales, 4 scale rows between the dorsal-fin ori- gin and the lateral line, 38 vertebrae, 12 branched anal-fin rays, 2 post-anal median scales to the anal-fin origin, 11 gill rakers on the lower limb of the first gill arch, the distance from the snout to the pectoral-fin insertion (24.7% of SL), the distance from the dorsal-fin origin to the anal-fin origin (26.0% of SL), the distance from dorsal-fin origin to the pectoral-fin insertion (27.8% of SL), the snout length (31.0% of SL), the postorbital head length (39.3% of HL), the well-developed third infraor- bital ventrally contacting the horizontal limb of the preopercle, the lack of a series of dark midlateral spots on the body, the ro- tund, albeit indistinct, humeral mark, the absence of chevron- shaped marks on the body, and the absence of a discrete patch of dark pigmentation on the middle portion of the anterior dor- sal-fin rays distinguishes Creagrutus molinus within the clade composed of Creagrutus and Piabina. DESCRIPTION.—Morphometric and meristic data for Crea- grutus molinus in Table 37. Head and body elongate, much more so than in the majority of its congeners. Greatest body depth at dorsal-fin origin. Dorsal profile of head distinctly con- vex from margin of upper lip approximately to vertical through posterior nostril, nearly straight from that point to rear of su- praoccipital spine. Predorsal profile of body slightly convex. Postdorsal profile of body nearly straight. Ventral profile of head and body gently convex from margin of upper lip to anal- fin origin. Obtuse angle at anteroventral corner of dentary obvi- ous in most congeners not apparent in this species. Head obtusely pointed in lateral and dorsal views. Upper jaw longer than, and overhanging, lower jaw. Anterior portion of snout fleshy, with numerous papillae over median region, up- per lip, lateral surface of maxilla, and on plicae and folds ex- tending between outer and medial premaxillary teeth. Lower lip thick and fleshy anteriorly, with numerous papillae along dorsal surface. Infraorbital series moderately well developed. Ventral mar- gin of third infraorbital contacting horizontal limb of preoper- cle. Posterior margins of third through fifth infraorbitals falling short of vertical limb of preopercle. Premaxillary dentition of the holotype (the only known spec- imen) proportionally relatively massive on one side of head; premaxillary dentition in process of replacement on other side of head. Premaxilla with only two of three major components typically present in other Creagrutus species. Primary row of premaxillary dentition consisting of 6 distally rounded teeth, with brown-tipped central raised point, without pronounced gap between first and second tooth of series; 6 partially devel- oped teeth in the process of replacement also apparent in main tooth row on right side. Single tooth, typically lateral to pri- mary row of premaxillary teeth in Creagrutus species, absent, and no space apparent on premaxilla onto which tooth would have attached. No indication of single replacement tooth on side of premaxilla in which teeth are in process of replacement. Triangular cluster of median teeth formed by 3 massive rounded teeth with central raised point. Three worn maxillary teeth present. Dentary with 3 massive teeth anteriorly. Total number of dentary teeth indeterminable without forcing open lower jaw and potentially damaging the unique specimen. Dorsal-fin rays ii,8. Dorsal fin located slightly anterior of vertical through pelvic-fin insertion. Profile of distal margin of dorsal fin straight. Anal-fin rays ii, 12. Profile of distal margin of anal fin distinctly concave. Mature male holotype with paired hooks present on all but distal segments of first branched pelvic-fin rays and some, but not most, of distal seg- ments of second branched ray. Hooks limited to main shaft and posterior branches of these rays. Pectoral-fin rays i , l l . Tip of pectoral fin extending posteriorly slightly more than three- fourths of distance to pelvic-fin insertion. Pelvic-fin rays i,6,i. Tip of pelvic fin extending posteriorly approximately three- fourths of distance to anal-fin origin. Mature males with hooks present on all branched anal-fin rays and on medial unbranched rays. Hooks distributed both on basal portion of ray and each segment, other than distalmost segment; limited to posterior margin of main shaft and posterior branch of branched rays ex- cept for medialmost ray having hooks on both branches. Gill rakers 7+11. NUMBER 613 161 FIGURE 66.—Creagrutus molinus, new species, holotype, MZUSP 41461, 55.8 mm SL; Brazil, Mato Grosso, Rio Araguaia basin, riacho (small stream) tributary to Ribeirao Lajeadinho, Municipio de Alto Araguaia (approximately 17°19'S, 53°12'W). FIGURE 67.—Map of central and northern South America showing geographic distribution of Creagrutus moli- nus (triangle, 1 =type locality), Creagrutus mucipu (diamond, 2=type locality), Creagrutus muelleri (squares; type locality inexact=Andes of Western Ecuador), Creagrutus occidaneus (dots, 3=type locality), Creagrutus ortegai (solid stars, 4=type locality), and Creagrutus ouranonastes (open star, 5=type locality) (some symbols represent more than one locality or lot of specimens). 162 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY COLORATION IN ALCOHOL.—Overall ground coloration yel- lowish, overlain midlaterally and on portions of head by gua- nine in single known specimen. Dorsal surface of head with field of small, dark chromatophores most concentrated over fontanelle. Chromatophore field denser over snout and upper lip. Region anterior to nares without dense concentration of chromatophores typical of many Creagrutus species. Region ventral of nares and along ventral margin of anterior portion of adipose eyelid with posteroventrally inclined band of small, dark chromatophores. Scattered, dark chromatophores over fourth and fifth infraorbitals and dorsal portion of opercle. Body with scattered, dark chromatophores over dorsolateral and dorsal surface, more concentrated dorsally, with chromato- phores denser along posterior region of scales in this region and forming dark, reticulate pattern. Humeral mark relatively faint, formed of small chromatophores arranged in irregularly rotund blotch; mark mostly located dorsal of lateral line. Faint midlateral stripe on posterior portion of caudal peduncle and on base of middle caudal-fin rays. Dorsal- and anal-fin rays out- lined by scattered, small, dark chromatophores. Caudal-fin rays mostly delimited by small, dark, chromatophores, other than for basal portions of rays lying dorsal and ventral of middle rays of fin. Pectoral and pelvic fins mostly hyaline. ETYMOLOGY.—The specific name, molinus, from the Latin for grinder, refers to the large teeth in the upper and lower jaws of this species. DISTRIBUTION.—Creagrutus molinus is known only from the type locality in the upper Rio Araguaia basin (Figure 67, trian- gle). COMPARISONS.—The distinctive premaxillary dentition characterized by large teeth limited to two of the three compo- nents typical for the species of Creagrutus, with a lack of the single tooth of form similar to that of primary series lateral to the primary tooth series, is unique to C. molinus in the genus. Within the greater Rio Tocantins drainage system, including the Rio Araguaia, C. molinus is distinguished from the other Creagrutus species of the basin by having 4 scales above the lateral line to the dorsal-fin origin (contrary to 5 in C. atri- signum and C. britskii), 12 branched anal-fin rays (contrary to 9 or 10 in C. Jigueiredoi and C. menezesi), 5 teeth in the pri- mary premaxillary tooth row and 38 vertebrae (contrary to 6 teeth in the primary premaxillary tooth row and 35 or 36 verte- brae in C mucipu), 9 to 11 gill rakers on the lower limb of the first arch and 41 lateral line scales (versus 13 or 14 rakers and 37 to 39 scales in C. saxatilis), and various proportional mor- phometric values (numbers 7, 8,11 in C. seductus, compare Ta- bles 37 and 53). REMARKS.—Creagrutus molinus is known only from a sin- gle specimen, which unfortunately was in the process of replac- ing its dentition in both the right dentary and premaxilla. The distinctive dentition apparent on the left side of the jaws and its overall appearance readily distinguish C. molinus from other Creagrutus species, and we describe it herein to draw attention to this unusual form. MATERIAL EXAMINED.—1 specimen (1, 55.8). HOLOTYPE.—BRAZIL. Mato Grosso: Rio Araguaia basin, riacho (small stream) tributary to Ribeirao Lajeadinho, Munici- pio de Alto Araguaia (approximately 17°19'S, 53°12'W); col- lected by L.P.S. Portugal and F. Langeani, MZUSP 41461, 1 (55.8). Creagrutus mucipu, new species FIGURES 67,68, TABLE 38 DIAGNOSIS.—The pattern of very dark, posteriorly directed, chevron-shaped pigmentation patches along the midlateral sur- face of the body is autapomorphic for Creagrutus mucipu among the species of Creagrutus and Piabina. Creagrutus mu- cipu also has the distal margin of the caudal fin outlined with a band of dusky pigmentation. This dark distal caudal-fin pig- mentation is separated from more basal dusky pigmentation by a hyaline region, a pigmentation pattern not found elsewhere in Creagrutus and Piabina. In addition to these autapomorphic pigmentation features, the combination of the possession of premaxillary dentition arranged in the three components gener- alized for most of the species of Creagrutus and Piabina with- out a pronounced gap between the first and second teeth of the primary series, 5 teeth in the primary series of each premaxilla, 3 maxillary teeth, 7 teeth on each dentary, 9 or 10 predorsal median scales, 2 post-anal median scales to the anal-fin origin, 36 to 39 lateral line scales without a lamellar process over each pore, 4 scale rows between the dorsal-fin origin and the lateral line, 11 branched anal-fin rays, 6 or 7 gill rakers on the upper limb and 9 to 11 gill rakers on the lower limb of the first arch, the distance from the snout to the dorsal-fin origin (45.0%-47.9% of SL), the distance from the dorsal-fin origin to the anal-fin insertion (32.4%-36.5% of SL), the caudal pe- duncle depth ( 1 2 . 5 % - 1 3 . 3 % of SL), the head length (24.9%-27.5% of SL), the snout length (24.5%-29.0% of HL), the postorbital head length (40.6%-44.8% of HL), the interor- bital width (29.7%-33.0% of HL), the well-developed third in- fraorbital whose straight ventral margin contacts the horizontal limb of the preopercle, the lack of a distinct spot of dark pig- mentation at the base of the middle caudal-fin rays, the faint, vertically elongate, ventrally attenuating humeral mark with straight anterior and posterior margins and lacking a secondary, dorsal patch of pigmentation, the absence of a distinct patch of pigmentation on the dorsal fin, and the lack of a series of dark, round spots along the midlateral surface of the body distin- guishes Creagrutus mucipu within the clade formed by Crea- grutus and Piabina. DESCRIPTION.—Morphometric and meristic data for Crea- grutus mucipu in Table 38. Head and body moderately robust; body more robust in larger individuals. Greatest body depth proportionally greater in larger individuals; at, or slightly ante- rior to, vertical through dorsal-fin origin in smaller examined paratypes; at dorsal-fin origin in larger examined individuals. Dorsal profile of head convex from margin of upper lip to NUMBER 613 163 TABLE 38.—Morphometrics and meristics of Creagrutus mucipu, new species: (A) holotype of C. mucipu, MCP 19511; and (B) paratypes of C. mucipu (n=8). Standard length is expressed in mm; measurements 1 to 14=percentages of standard length; 15 to 18=percentages of head length. Characters Standard length 1. Snout to anal-fin origin 2. Snout to pelvic-fin insertion 3. Snout to pectoral-fin insertion 4. Snout to dorsal-fin origin 5. Dorsal-fin origin to hypural joint 6. Dorsal-fin origin to anal-fin origin 7. Dorsal-fin origin to pelvic-fin insertion 8. Dorsal-fin origin to pectoral-fin insertion 9. Caudal peduncle depth 10. Pectoral-fin length 11. Pelvic-fin length 12. Dorsal-fin length 13. Anal-fin length 14. Head length 15. Postorbital head length 16. Snout length 17. Bony orbital diameter 18. Interorbital width Lateral line scales Scale rows between dorsal-fin origin and lateral line Scale rows between anal-fin origin and lateral line Predorsal median scales Branched dorsal-fin rays Branched anal-fin rays Branched pelvic-fin rays Pectoral-fin rays Vertebrae A B Morphometrics 50.1 65.3 47.5 26.7 46.1 59.1 35.7 30.1 34.1 12.8 20.4 17.2 21.8 19.6 27.5 41.9 24.5 32.2 29.7 37.6-56.1 62.0-66.0 46.2-48.9 24.3-26.4 45.0^7.9 57.6-59.6 32.4-36.5 28.5-32.6 32.1-36.2 12.5-13.3 19.2-22.3 16.0-18.5 21.5-23.4 18.0-20.4 24.9-27.2 40.6-44.8 24.6-29.0 32.4-36.4 29.9-33.0 Meristics 39 4 3 9 8 11 7 13 36 36-39 4 3 9-10 8 11 5-7' 12-14 35-36 1 Five branched anal-fin rays present on only on one pelvic fin of 1 of 8 paratypes; 7 branched anal-fin rays limited to larger specimens. slightly posterior of vertical through posterior nostril, then nearly straight to tip of supraoccipital spine. Interorbital region transversely convex. Predorsal profile of body slightly convex, with moderate change in alignment relative to profile of poste- rior portion of head. Predorsal region of body with obtuse me- dian ridge along posterior half of its length in larger specimens. Prepelvic profile of lower jaw with obtuse angle at anteroven- tral corner of dentary. Ventral profile of head posterior to ob- tuse angle on dentary slightly convex to isthmus. Ventral pro- file of body slightly convex overall and continuing profile of ventral profile of head. Prepelvic region of body obtusely flat- tened transversely. Head obtusely rounded in lateral view, but more compressed transversely in dorsal view. Upper jaw slightly longer than, and overhanging, lower jaw. Snout fleshy anteriorly, with scattered papillae on anterior surface, papillae field continuing onto fleshy folds between premaxillary teeth. Lower lip fleshy ante- riorly, with scattered papillae on upper and anterior portions. Infraorbital series well developed. Ventral margin of third in- fraorbital straight and contacting horizontal limb of preopercle in specimens of all available sizes. Posterior margins of third through fifth infraorbitals approaching, but not contacting, ver- tical limb of preopercle; gap narrow in specimens of all avail- able sizes. Premaxillary dentition in three series: primary row arched, with 5 teeth, without pronounced gap between first and second tooth of series; triangular cluster of 3 larger teeth, without pro- nounced gap between first and second tooth of series but with medial teeth of contralateral clusters nearly in contact; and sin- gle tooth of form similar to that of primary series occurring lat- eral to third tooth of primary tooth row. Maxilla with 3 tricusp- idate teeth. Dentary with 5 or 6 tricuspidate teeth. Second dentary tooth somewhat larger than first tooth and distinctly larger and about approximately one and one-half times vertical extent of third tooth; fourth tooth distinctly smaller than third tooth; fourth through last teeth in series progressively gradually decreasing in size. Dorsal-fin rays ii,8 in all specimens. Distal margin of dorsal fin slightly concave. Anal-fin rays ii, 11 in all specimens. Distal margin of anal fin concave. Anal-fin hooks present on first, first and second, or first through third rays of mature males. Pectoral-fin rays i, 11-13. Tip of pectoral fin reaching posteri- orly nearly to pelvic-fin insertion. Pelvic-fin rays i,5-7; 5 branched rays limited to pelvic fin on one side of one speci- men; 7 branched rays occurring only in larger examined speci- mens. Tip of pelvic fin reaching posteriorly nearly to anal-fin origin. Pelvic-fin hooks present on 5 or 6 branched rays in ma- ture males; medial branched ray lacking hooks when only 5 hook-bearing rays present. Gill rakers 6-7 + 9-11. COLORATION IN ALCOHOL.—Ground coloration of specimen very light tan to tan. Dorsal surface of head in smaller individu- als with dense field of dark chromatophores on membranes overlying brain and with field of scattered, smaller, dark chro- matophores on surface of head; chromatophore concentration distinctly less pronounced anteriorly. Surface chromatophore field gradually becoming more concentrated in larger speci- mens and forming field of dense pigmentation in larger speci- mens, albeit somewhat less concentrated on dorsal surface of snout. Region anterior to nostrils with only slightly more con- centrated field of dark chromatophores in specimens of all sizes; these not forming distinct crescent-shaped patch in that region such as found in many congeners. Area anteroventral to orbit with diffuse field of small, dark chromatophores extend- ing from ventral margin of nares to ventral margin of orbit. Dorsal portion of opercle and lateral surface of fourth though sixth infraorbitals with scattered, stellate, dark chromatophores in smaller individuals; chromatophore field extending some- what more ventrally and to a degree under orbit in larger speci- mens. Scales on dorsal portion of body with exposed margins out- lined by small, dark chromatophores, giving region overall 164 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY FIGURE 68.—Creagrutus mucipu, new species, holotype, MCP 19511, 50.1 mm SL; Brazil, Goias, Municipio de Minacu, Rio Tocantins, at port of Rubao (13°44'31"S, 48°08'29"W). dark, reticulate, pigmentation pattern. Midlateral region of body with series of dark, chevron-shaped marks formed by deep-lying chromatophores. Individual chevron-shaped marks with arms relatively straight, sometimes with secondary branches extending at angles from main body of mark. Chev- ron pattern most obvious in region ventral of dorsal fin, becom- ing less apparent on body posteriorly. Dorsal portions of chev- rons more obvious than ventral portions in many individuals, particularly smaller specimens. Ventral portion more apparent in most larger individuals. Humeral mark formed of relatively faint to distinct, small, dark chromatophores. Overall form of humeral mark vertically elongate and ventrally attenuating, with anterior and posterior margins somewhat variable, ranging from relatively straight to having concave anterodorsal and posterodorsal margins, or convex anterodorsal margin. Hu- meral mark extending dorsally to one scale from middorsal line and ventrally to level approximately one scale dorsal of hori- zontal through dorsal limit of pectoral-fin insertion. Faint mid- lateral body stripe formed by small, dispersed, dark chromato- phores extending from about 2 scales posterior of humeral mark posteriorly to rear of caudal peduncle. Stripe widest and overlying dark chevron-like marks anteriorly, gradually nar- rowing and only partially overlapping dark midlateral marks along posterior portion of body. Stripe merging into field of scattered, dark chromatophores on caudal peduncle. Dorsal fin with small dark chromatophores on membranes and outlining many fin rays. Anal fin with scattered, dark chro- matophores on distal two-thirds of membranes of branched rays. Pectoral fin with small chromatophores on membranes. Pelvic fin hyaline. Caudal fin with basal dusky pigmentation extending out along rays of each lobe. Distal margin of caudal fin outlined by band of diffuse dark pigmentation. Distal and basal regions of caudal pigmentation separated by hyaline re- gion. ETYMOLOGY.—The species name, mucipu, is an acronym derived from Museu de Ciencias e Tecnologia, PUCRS (Pon- tificia Universidade Catolica do Rio Grande do Sul) whose staff collected the holotype of the species and brought it to our attention, and who have provided valuable assistance to the au- thors in this and other projects. It is treated as a noun in apposi- tion. ECOLOGY.—The holotype and paratypes, the only know specimens of Creagrutus mucipu, were collected in residual ponds in the bed of the Rio Tocantins following the interrup- tion of water flow through the channel as a result of the closure of a dam, the Repressa da Usina Hidroelectica de Serra da Mesa. The natural habitat of C. mucipu is, thus, unknown, but the river had clear water and a bottom of small stones and rocks prior to the dam closure (C. Lucena, pers. comm., 2000). The paratype series of C. mucipu was collected together with speci- mens of C. menezesi and C. figueiredoi. A female that was pre- pared for clearing and staining in this study (USNM 350449, 41.4 mm SL) had numerous well-developed eggs. It was col- lected in the late October to early November period of 1996. SEXUAL DIMORPHISM.—The relatively small available sam- ple of Creagrutus mucipu shows a definite difference in the rel- ative size of the two sexes. Mature males, as indicated by the presence of body hooks on the anterior rays of the anal fin and on the branched rays of the pelvic fin range from 37.6 to 44.9 mm SL (n=3). Females lacking those modifications range from 40.8 to 56.1 mm SL (n=6). DISTRIBUTION.—Creagrutus mucipu is known only from the type locality in the upper portions of the Rio Tocantins basin (Figure 67, diamond). REMARKS.—Although Creagrutus mucipu is known only from a limited series of specimens, its distinctive features, in particular the pattern of dark chevron-shaped pigmentation patches along the midlateral surface of the body and the cau- dal-fin pigmentation, readily distinguish it from all congeners. MATERIAL EXAMINED.—9 specimens (9, 37.6-56.1). HOLOTYPE.—BRAZIL. Goias: Municipio de Minacu, Rio Tocantins, at port of Rubao (13°44'31"S, 48°08'29"W), col- NUMBER 613 165 lected by C.A.S. Lucena and J.J.P. Silva, 7 Nov 1996; MCP 19511, 1(50.1). PARATYPES.—8 specimens (8, 37.6-56.1). BRAZIL. Goids: Municipio de Minacu/Colinas do Sul. Rio Tocantins, in large pools below dam of Usina Hidroelectica de Serra da Mesa following closure of dam to fill reservoir (ap- proximately 13°44'S, 48°08'W), collected by D.F. Moraes et al., 28 Oct to 3 Nov 1996, MNRJ 17337,6 (37.6-56.1); USNM 350449,2(41.4-51.7). Creagrutus muelleri (Giinther, 1859) FIGURES 67,69, TABLE 39 Leporinus miilleri Giinther, 1859:92 [type locality: Andes of Western Ecua- dor]. Creagrutus miilleri.—Giinther, 1864:339 [redescription based on Gunther (1859); designated as type species of Creagrutus Giinther].—Steindachner, 1882b:20 [Ecuador (Pastaza) Canelos].—Eigenmann and Eigenmann, 1891:14 [listing].—Eigenmann, 1910:435 [in part, Ecuador; not synonymy of Creagrutus qffinis Steindachner or reported occurrence of C. miilleri in [Rio] Cauca [Colombia]]; 1927:420, pi. 35: figs. 6, 7 [based on Gunther's 1864 account].—Eigenmann and Allen, 1942:227 [literature listing; not re- ported occurrence of species in [Rio] Cauca [Colombia]].—Fowler, 1943b:l [Ecuador, Tungurahua, Rio Pastaza, Hacienda Las Mascota].—Barriga, 1991:17 [eastern Ecuador].—Not Bohlke, 1958:30.—Not Saul 1975:106. Creagrutus muelleri.—Fowler, 1948:84 [literature compilation]; 1975:26 [lit- erature compilation].—Gery, 1977:407 [in key].—Gery and Renno, 1989, fig. 4b [maxillary dentition].—Barriga, 1994:29 [Ecuador, Parque Nacional Yasuni].—Not Boulenger, 1887. Creagrutus mulleri.—Ovchynnyk, 1968:246 [Ecuador, eastern slopes of Andes]. Creagrutus aff. mulleri.—Barriga, 1982:64 [Ecuador, Zamora-Chinchipe: Rio Nangaritza, Rio Samora, Quebrada Tunanza; life history; common name]. DIAGNOSIS.—The possession of premaxillary dentition with the three components generalized for the species of Creagru- tus, but with a distinct gap between the first and second teeth of primary tooth row and a forward position of the triangular clus- ter of three posteromedial teeth distinguishes C. muelleri from all members of the clade formed by Creagrutus and Piabina with the exception of Creagrutus maracaiboensis, C. melanzo- nus, C. nigrostigmatus, C. ouranonastes, C. peruanus, C. runa, and Piabina argentea. Creagrutus muelleri can be distin- guished from these seven species by the combination of the possession of 39 to 41 lateral line scales, 11 to 13 predorsal me- dian scales, 10 to 12 branched anal-fin rays, 39 or 40 vertebrae, the relatively wide third infraorbital nearly contacting the hori- zontal and vertical limbs of the preopercle, the distance from the snout to the anal-fin origin (60.1%-65.6% of SL), the anal- fin length (15.3%-17.8% of SL), the caudal peduncle depth ( 1 1 . 7 % - 1 3 . 4 % of SL) , the bony orbi ta l d i ame te r (24.9%-29.7% of HL), and the absence of two small distinct spots of dark pigmentation on the basal portion of the caudal fin. DESCRIPTION.—Morphometric andmeristic data for Crea- grutus muelleri in Table 39. Overall body relatively robust, particularly anteriorly. Greatest body depth at vertical through dorsal-fin origin in specimens of approximately 30 mm SL, TABLE 39.—Morphometrics and meristics of Creagrutus muelleri: (A) lecto- type of C. muelleri. BMNH 1858.7.25:42; and (B) all other specimens of C. muelleri from which counts and measurements were taken (n=26). Standard length is expressed in mm; measurements I to 14=percentages of standard length; 15 to 18=percentages of head length. Characters Standard length 1. Snout to anal-fin origin 2. Snout to pelvic-fin insertion 3. Snout to pectoral-fin insertion 4. Snout to dorsal-fin origin 5. Dorsal-fin origin to hypural joint 6. Dorsal-fin origin to anal-fin origin 7. Dorsal-fin origin to pelvic-fin insertion 8. Dorsal-fin origin to pectoral-fin insertion 9. Caudal peduncle depth 10. Pectoral-fin length 11. Pelvic-fin length 12. Dorsal-fin length 13. Anal-fin length 14. Head length 15. Postorbital head length 16. Snout length 17. Bony orbital diameter 18. Interorbital width Lateral line scales Scale rows between dorsal-fin origin and lateral line Scale rows between anal-fin origin and lateral line Predorsal median scales Branched dorsal-fin rays Branched anal-fin rays Branched pelvic-fin rays Pectoral-fin rays Vertebrae A B Morphometrics 82.5 35.1-108.3 61.7 60.1-65.6 44.7 43.0-48.3 23.9 21.6-25.8 49.8 47.3-51.0 56.1 53.7-58.9 30.7 28.6-31.6 29.0 25.0-29.9 33.1 31.3-35.8 12.7 11.7-13.4 20.0 19.0-20.9 14.5 14.4-15.7 18.2 17.8-22.4 16.2 15.3-17.8 25.8 23.7-26.5 54.0 47.3-54.1 24.5 24.4-29.4 25.3 24.9-29.7 34.2 30.0-34.8 Meristics 41 39-41 4 4-5 3 3-4 13 11-13 8 7-8' 10 1O-122 6 5-63 13 12-14 40 39-40 'Seven branched dorsal-fin rays present in only 1 of 26 specimens. 2Ten and 11 branched anal-fin rays most common, 12 rays present in only 2 of 26 specimens. 3Five branched pelvic-fin rays present in only 1 of 26 specimens. shifting somewhat anterior of that point in larger individuals, more notably in specimens with distended abdomens. Dorsal profile of head smoothly curved from margin of upper lip to vertical through posterior nostril, straight, or nearly so, from that point to rear of supraoccipital spine. Dorsal profile of body gently convex from rear of supraoccipital spine to dorsal-fin origin at all body sizes, convexity somewhat more pronounced in larger examined specimens. Profile posteroventrally angled along dorsal-fin base and nearly straight from posterior of dor- sal-fin base to caudal peduncle in smaller specimens. Changes in profile at anterior and posterior insertions of dorsal fin less notable in larger specimens. Ventral profile of head convex, with barely apparent obtuse angle at anteroventral region of dentary. Ventral profile of body between isthmus and pelvic fin convex; convexity more pronounced in larger specimens. Head obtusely pointed in lateral view and more obviously pointed in dorsal view. Upper jaw longer than, and slightly 166 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY overhanging, lower jaw. Anterior portion of snout fleshy, with scattered papillae that extend onto lips and on folds and plicae extending between outer and medial premaxillary teeth. Larger individuals with field of large papillae all over head. Infraorbital series moderately well developed. Large portion of ventral margin of third infraorbital in contact with horizontal limb of preopercle. Posterior margins of third through fifth in- fraorbitals not contacting vertical limb of preopercle; gap be- tween infraorbitals and vertical limb of preopercle decreasing slightly dorsally. Premaxillary teeth in three series: primary row curved, con- sisting of 5 teeth, with distinct gap between first and second tooth and between medial teeth of contralateral series; triangu- lar cluster of three teeth with anterior tooth approximately same size as teeth of primary row and slightly medial to pro- nounced gap between first and second teeth of primary row, two other teeth of medial cluster, particularly posteromedial tooth, larger than remaining teeth in jaw; and single tooth of form similar to that of primary series lying lateral to area of contact of third and fourth teeth of primary premaxillary row. Maxilla with 3 or 4 tricuspidate teeth. Dentary with 5 or 6 tri- cuspidate teeth. Three anterior dentary teeth distinctly larger than other teeth in series, with second tooth slightly larger than first tooth. Third tooth approximately two-thirds height of sec- ond tooth. Middle cusp on anterior 3 teeth particularly well de- veloped. Last 2 or 3 teeth on dentary compressed, tricuspidate, and distinctly smaller than third tooth and becoming progres- sively smaller posteriorly. Dorsal-fin rays typically ii,8; very rarely ii,7. Dorsal-fin ori- gin at vertical through pelvic-fin insertion. Profile of distal margin of dorsal fin slightly convex in smaller individuals, nearly straight in largest examined specimens. Anal-fin rays ii,10-12. Profile of distal margin of anal fin very slightly con- cave. Hooks typically present on anal-fin rays in mature males of many Creagrutus species not present in examined speci- mens. Pectoral-fin rays i, 11-13. Tip of pectoral fin extending posteriorly nearly to pelvic-fin insertion in smaller specimens, only approximately two-thirds of distance in larger specimens. Pelvic-fin rays typically i,6,i, one specimen with i,5,i. Tip of pelvic fin extending posteriorly to anus. Hooks typically present on pelvic-fin rays in mature males of many Creagrutus species not present in examined specimens. Gill rakers 7-8+10-11. COLORATION IN ALCOHOL.—Ground coloration of speci- mens collected within the last two decades tan to light brown. Dorsal surface of head with scattered, small, dark chromato- phores overlying deep-lying chromatophores over membranes of brain. Region anterior to nostrils somewhat more intensely pigmented, but without distinct crescent-shaped patch of dark pigmentation found in this region in some congeners. Lateral surface of head with scattered, dark chromatophores, chro- matophores more concentrated on dorsal portions of opercle and infraorbitals. Body pigmentation darker dorsally, with dis- tinctly darker pigmentation over center of scales dorsally and dorsolaterally. Margins of scales less intensely pigmented, with chromatophores forming dark, reticulate pattern on dorsolateral portions of body. Deep-lying obscure, dark band along midlat- eral surface of body. Humeral mark irregularly shaped, but ver- tically elongate overall. Mark ventrally attenuate with some- what less intensely pigmented region extending up to one-half scale ventral of lateral line. Anterior margin of humeral mark slightly concave. Margins of fin-rays of dorsal, anal, and caudal fins outlined with small, dark chromatophores, giving fins, particularly cau- dal fin, dusky overall appearance. Paired fins hyaline to slightly dusky. ECOLOGY.—Barriga (1982:67) reported that in southeastern Ecuador this species (identified therein as Creagrutus aff. mul- leri) inhabits large rivers with strong currents, turbid waters, and muddy bottoms, but within that region it was collected in regions of pebble beaches. Creagrutus muelleri feeds most commonly on seeds, but some individuals also had fed on insect larvae and fish scales (Barriga, 1982:67). Stomach contents of specimens prepared for clearing and staining in this study consisted of parts of lar- vae and adult insects, and chopped-up seeds. A female col- lected in September has ovaries full of eggs. COMMON NAME.—Southeastern Ecuador: "Blancos" (Bar- riga, 1982:64). DISTRIBUTION.—Creagrutus muelleri occurs in the rivers draining the eastern slopes of the Andean piedmont in Ecuador (Figure 67, squares). REMARKS.—There are five specimens presently identified as the syntypes of Leporinus mulleri (BMNH 1858.7.25:42-45), four of which were examined during this study. Two of those individuals, distinctly smaller than the other specimens in the type series, are individuals of Ceratobranchia Eigenmann, a characiform genus apparently not closely related to Creagrutus and whose characters, particularly dentition (see illustrations of teeth of Ceratobranchia in Chernoff and Machado-Allison, 1990), differ significantly from those of Creagrutus and Pia- bina. Giinther (1859) did not explicitly note how many specimens served as the basis for his original description of Leporinus mulleri. Nonetheless, the detailed information on the number of pyloric caeca and vertebrae in the original description of the species must have been based on a dissected specimen. One of the two examined Creagrutus specimens in the type series of Leporinus mulleri, an 82.5 mm SL individual, has been dis- sected in a manner as to provide the information cited by Giinther. Given that this specimen is obviously the individual that served as the basis for much of the information in the orig- inal description of the species, it is herein designated as the lec- totype of Leporinus mulleri (BMNH 1858.7.25:42). The other four syntypes, at least two of which are specimens of Cerato- branchia, become paralectotypes. The original description of Creagrutus muelleri provided by Giinther (1859) was relatively brief, and his description of its NUMBER 613 167 FIGURE 69.—Creagrutus muelleri, USNM 340984, 72.5 mm SL; Ecuador, Pastaza, Rio Pastaza, tributary stream 2 km downstream of Cumanda (1°27'S, 78°08'W). dentition, particularly of the premaxillary teeth, was subject to alternate interpretations, a problem with many descriptions of the dentition in the genus. As a consequence several subse- quent identifications of the species have proven to be errone- ous. Bohlke (1958:30) reported Creagrutus mulleri from a number of localities in eastern Ecuador. In his description of C. boehlkei, Gery (1972:65) equated Bohlke's material with that species. A reappraisal has shown that Bohlke's specimens were mostly C. amoenus (a senior synonym of C. boehlkei) with some lots of C. kunturus, a species very similar in overall ap- pearance to C. amoenus, which also occurs in eastern Ecuador. Saul (1975:106) reported on the food and habitat preferences of material he identified as Creagrutus muelleri. These speci- mens have proved to be C. amoenus. MATERIAL EXAMINED.—41 specimens (27, 35.1-108.3). ECUADOR. "Andes of Western Ecuador ," BMNH 1858.7.25:42, 1 (82.5, lectotype of Leporinus mulleri); BMNH 1858.7.25:43, 1 (78.3, paralectotype of Leporinus mulleri). Tungarahua: N shore of Rio Pastaza below town of Rio Negro (1°24'S, 78°13'W), KU 20003, 10 (35.1-74.2). Rio Pastaza, Hacienda Las Mascota, ANSP 70154, 1 (88.0). Pastaza: Rio Pastaza, tributary stream 2 km downstream of Cumanda (1°27'S, 78°08'W), USNM 340984, 10 (6, 38.9-72.5; 2 speci- mens cleared and counterstained for cartilage and bone). Zamora Chincipe: Rio Zamora, near city of Zamora (4°04'S, 78°08'W), MEPN 4637, 1 (57.0); MEPN 4638, 1 (53.3). Rio Nangaritza, near village of Guayzimi (4°02'S, 78°40'W), MEPN 4636, 2 (48.2-78.0) . Rio Nangaritza (3°45'S, 78°36'W), MEPN 6195, 10. Rio Zamora above mouth of Rio Jamboe (approximately 4°04'S, 78°56'W), USNM 340983, 4 (60.0-108.3; 1 specimen cleared and counterstained for carti- lage and bone). Creagrutus occidaneus, new species FIGURES 67, 70, TABLE 40 DIAGNOSIS.—The combination of the possession of premax- illary dentition arranged in the three components generalized for most of the species of Creagrutus and Piabina without a distinctly larger gap between the first and second teeth of the primary series, 3 or 4 teeth on the maxilla, 6, rarely 5, teeth in the primary tooth row of the premaxilla, 4 or 5 dentary teeth, 38 to 43 lateral line scales without a lamellar process over each pore, 9 or 10 predorsal median scales, 3 or 4 scale rows be- tween the dorsal-fin origin and the lateral line, 37 to 39 verte- brae, 10 or 11 branched anal-fin rays, 2 post-anal median scales to the anal-fin origin, 6 to 8 gill rakers on the upper limb of the first gill arch, 11 to 13 gill rakers on the lower limb of the first gill arch, the bony orbital diameter (32.6%-37.9% of HL), the anal-fin length (15.9%-19.5% of SL), the distance from the dorsal-fin origin to the anal-fin origin (30.3%-36.0% of SL), the distance from the dorsal-fin origin to the pelvic-fin inser- tion (25.4%-30.8% of SL), the distance from the dorsal-fin ori- gin to the pectoral-fin insertion (30.9%-35.8% of SL), the cau- dal peduncle depth (10.9%-12.8% of SL), the head length (24.1%-27.7% of SL), the postorbital length (41.0%-46.1% of HL), the interorbital width (29.9%-32.9% of HL), the well-de- veloped third infraorbital approaching, or in some specimens contacting, the horizontal limb of the preopercle, the lack of a series of dark midlateral spots on the body, the vertically elon- gate, ventrally tapering humeral mark, the lack of a large spot of pigmentation on the basal portions of the middle caudal-fin rays, and the absence of a discrete patch of dark pigmentation on the middle portion of the anterior dorsal-fin rays distin- guishes Creagrutus occidaneus within the clade compose of Creagrutus and Piabina. 168 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY TABLE 40.—Morphometrics and meristics of Creagrutus occidaneus, new spe- cies: (A) holotype of C. occidaneus. MUSM 8869; and (B) paratypes of C. oc- cidaneus (n=27). Standard length is expressed in mm; measurements 1 to 14= percentages of standard length; 15 to 18=percentages of head length. Characters Standard length 1. Snout to anal-fin origin 2. Snout to pelvic-fin insertion 3. Snout to pectoral-fm insertion 4. Snout to dorsal-fin origin 5. Dorsal-fin origin to hypural joint 6. Dorsal-fin origin to anal-fin origin 7. Dorsal-fin origin to pelvic-fin insertion 8. Dorsal-fin origin to pectoral-fin insertion 9. Caudal peduncle depth 10. Pectoral-fin length 11. Pelvic-fin length 12. Dorsal-fin length 13. Anal-fin length 14. Head length 15. Postorbital head length 16. Snout length 17. Bony orbital diameter 18. Interorbital width Lateral line scales Scale rows between dorsal-fin origin and lateral line Scale rows between anal-fin origin and lateral line Predorsal median scales Branched dorsal-fin rays Branched anal-fin rays Branched pelvic-fin rays Pectoral-fin rays Vertebrae A B Morphometrics 60.4 62.9 45.5 24.2 44.2 60.4 32.3 27.6 31.3 11.1 19.3 15.9 21.2 17.1 26.2 45.6 26.6 33.4 30.0 26.8-65.9 61.8-69.2 44.3-51.0 23.0-26.8 44.1-49.5 55.3-60.7 30.3-36.0 25.4-30.8 30.9-35.8 10.9-12.8 19.0-22.2 13.6-17.0 20.1-25.7 15.9-19.5 24.1-27.7 41.0-46.1 25.5-30.9 32.6-37.9 29.9-32.9 Meristics 42 4 3 10 8 11 6 13 39 38-43 3-41 3 9-10 8 10-11 6 12-13 37-39 Three scales between anal-fin origin and lateral line present in only 1 of 27 paratypes. DESCRIPTION.—Morphometric and meristic data for Crea- grutus occidaneus in Table 40. Head moderately robust, body- ranging from moderately elongate in some mature males to rel- atively robust in gravid females. Greatest body depth typically at dorsal-fin origin, but shifted anterior of that point in some gravid females. Dorsal profile of head gently convex from tip of snout to vertical through posterior nostril, straight from that point to tip of supraoccipital spine. Interorbital region slightly convex transversely. Predorsal profile straight and continuous with dorsal profile of body in smaller individuals, becoming slightly convex, with variably distinct change in alignment rel- ative to profile of head in larger specimens. Dorsal surface of body with distinct median ridge extending anteriorly from dor- sal-fin insertion approximately one-half of distance to tip of su- praoccipital spine. Ventral profile of head with obvious obtuse angle at anteroventral corner of dentary, nearly straight from that angle to rear of isthmus. Ventral profile of body ranging from nearly straight in smaller specimens and mature males to distinctly convex in gravid females. Prepelvic region of body obtusely flattened transversely. Head somewhat pointed in lateral view, more so in dorsal view. Upper jaw not very fleshy, longer than, and distinctly overhanging, lower jaw. Snout not very fleshy, with scattered papillae anteromedially; papillae concentrated along upper lip and on folds and plicae extending between outer and medial premaxillary teeth. Lower jaw fleshy, more so anteriorly, with numerous papillae on dorsal margin of lip and scattered papil- lae on anterior surface of jaw. Infraorbital series moderately well developed. Anterior one- half of ventral margin of third infraorbital falling slightly short of or, more rarely, contacting horizontal limb of preopercle. Posterior margins of third through fifth infraorbitals falling dis- tinctly short of vertical limb of preopercle. Premaxillary dentition in three series: primary row typically consisting of 6, sometimes 5, teeth arranged in nearly straight to slightly sigmoid series without pronounced gap between first and second tooth of series; triangular cluster of slightly larger teeth with posterolateral tooth largest; and typically single tooth of form similar to that of primary series lying lateral to fourth tooth of primary premaxillary series, or lateral to area of contact of third and fourth teeth of primary series; few speci- mens with 2 teeth lying lateral to area of contact of fourth tooth with third and fifth teeth respectively. Maxilla with 3 or 4 tri- cuspidate teeth. Dentary with 4 or 5 tricuspidate teeth; first and second teeth distinctly larger than remaining teeth in series, with second tooth somewhat larger than first tooth; third tooth only approximately one-third vertical extent of second tooth, but about 3 times height of fourth tooth. Fifth tooth, when present, smaller than fourth tooth. Dorsal-fin rays ii,8 in all examined specimens. Dorsal-fin or- igin at, or slightly anterior to, vertical through pelvic-fin inser- tion. Profile of distal margin of dorsal fin slightly concave. Anal-fin rays ii, 10-11. Profile of distal margin of anal fin nearly straight in smaller individuals, increasingly concave in larger specimens. Mature males with hooks occasionally present on last unbranched anal-fin ray and anterior 2 to 4 branched anal-fin rays. Pectoral-fin rays i, 11-12. Tip of pecto- ral fin extending posteriorly slightly over three-fourths of dis- tance to pelvic-fin insertion. Pelvic-fin rays i,6,i. Tip of pelvic fin extending posteriorly to, or falling slightly short of, anus. Hooks present on all branched pelvic-fin rays in mature males. Gill rakers 6-8+11-13. COLORATION IN ALCOHOL.—Ground color of specimens in alcohol tan. Dorsal surface of head with scattered field of small superficial dark chromatophores and obscure field of deep-ly- ing, very dark chromatophores overlying membranes of brain. Chromatophore field more concentrated anteriorly on head, over snout, and on portions of upper lip. Region of snout ante- rior to nostrils with concentrated chromatophores forming dark, crescent-shaped patch continuous posteroventrally with narrow band of dark chromatophores extending along ventral and posterior margins of orbit. Dorsal portions of opercle and NUMBER 613 169 FIGURE 70.—Creagrutus occidaneus, new species, holotype, MUSM 8869, 60.4 mm SL; Peru, Madre de Dios, Provincia Manu, Parque Nacional Manu, Pakitza, beach along Rio Manu close to mouth of Quebrada Pachija (approximately 11 °57'S, 71 ° 17'W). all infraorbitals posterior to orbit with scattered, dark chro- matophores. Dark pigmentation on head obscured by surface guanine layer in many specimens. Scales of dorsal portion of body with diffuse chromatophore field on basal portions of exposed field and some scattered chromatophores along distal margin resulting in dark, reticulate pigmentation pattern on those portions of body. Humeral mark prominent, distinctly tapering ventrally, extending ventrally ap- proximately one-half of scale below lateral line and dorsally about two scales above lateral line. Margins of humeral mark somewhat variable, but distinct dorsally. Diffuse midlateral band formed of small, dark chromatophores extending from slightly posterior of humeral mark to middle of caudal pedun- cle. Dorsal fin with anterior margin of last unbranched ray and basal portions of branched fin rays outlined by dark chromato- phores. Membranes of anterior rays with scattered, dark chro- matophores, extent of chromatophore field more extensive an- teriorly. Anal fin with scattered, dark chromatophores on membranes in some individuals. Caudal fin with scattered, light brown chromatophores over membranes and rays. Pecto- ral and pelvic fins hyaline. ETYMOLOGY.—The specific name, occidaneus, from the Latin for western, refers to the distribution of the species along the western lowlands of the Amazon basin. ECOLOGY.—The type locality was a white-water rainforest stream with a sandy bottom at an elevation of approximately 325 m. Other Peruvian localities for which habitat data is avail- able had similar water conditions with substrates of mixed rub- ble, silt, sand, gravel, and clay. These localities ranged between 190 and 290 m elevation. SEXUAL DIMORPHISM.—The examined samples of Creagru- tus occidaneus apparently do not demonstrate the distinct size difference between mature males and females found in many members of the genus. Mature males, as shown by the presence of well-developed hooks on the anal and pelvic fins, ranged from 38.6 to 61.1 mm SL, whereas females measured up to only 65.9 mm SL. DISTRIBUTION.—Creagrutus occidaneus is distributed across the foothills and lowlands of eastern Peru in the Rio Manu ba- sin of the Department of Madre de Dios and in the upper Rio Purus basin in the states of Acre and Amazonas, Brazil, and the Department of Ucayali, Peru (Figure 67, dots). REMARKS.—The majority of the specimens of Creagrutus occidaneus, including all larger individuals, were collected in the upper portions of the Madre de Dios basin in southeastern Peru. Several lots of mostly juvenile specimens from the states of Acre and Amazonas, Brazil, and the Department of Ucayali in the western portions of the Rio Purus basin in Peru (see "Nontype Specimens," below) were not found to differ from juveniles collected in Rio Madre de Dios basin of Peru. Sam- ples of adults from these Brazilian and eastern Peruvian rivers are necessary to confirm whether those populations and that in the Rio Madre de Dios basin are indeed conspecific. MATERIAL EXAMINED.—183 specimens (33, 26.8-65.9). HOLOTYPE.—PERU. Madre de Dios: Provincia Manu, Parque Nacional Manu, Pakitza, beach along Rio Manu close to mouth of Quebrada Pachija (approximately 11°57'S, 71°17'W), collected by H. Ortega and F. Pinares, 9 Oct 1991, MUSM 8869, 1 (60.4). PARATYPES.—27 specimens (27, 26.8-65.9). PERU. Madre de Dios: Provincia Manu, Parque Nacional Manu, Pakitza, beach along Rio Manu close to mouth of Que- brada Pachija (approximately 11°57'S, 71°17'W), collected with holotype, MUSM 8870, 4 (26.8-63.9); USNM 326920, 7 (38.3-65.9; 2 specimens cleared and counterstained for carti- lage and bone). Provincia Manu, mouth of Rio Pinquen, near Boca Manu (12°10'S, 71°01'W), collected by R. Horwitz, 4 Aug 1977, ANSP 143765, 1 (61.3). Provincia Manu, Rio Manu, approximately 2 hours by boat upstream from Boca Manu, collected by H. Ortega et al., 7 Sep 1988, USNM 303065, 1 (50.7). Provincia Manu, Parque Nacional Manu, Pa- 170 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY kitza and vicinity (approximately 11°57'S, 71°17'W), collected by H. Ortega, Oct 1987, USNM 295621, 9 (49.0-61.8); MUSM 8871, 5 (29.9-56.1). NONTYPE SPECIMENS.—155 specimens (5,46.8-60.5). PERU. Madre de Dios: Provincia Manu, Parque Nacional Manu, Pakitza and vicinity (approximately 11°57'S, 71°17'W), USNM 295571, 5 (46.8-60.5). Provincia Manu, Parque Nacio- nal Manu, Rio Manu, near mouth of Quebrada Fortaleza, USNM 319661, 1. Provincia Manu, Parque Nacional Manu, Pakitza, Quebrada Fortaleza, USNM 326875, 2. Provincia Manu, Parque Nacional Manu, Rio Manu, Quebrada Fortaleza, 15 m above mouth, USNM 319657, 1. Provincia Manu, Parque Nacional Manu, Rio Manu at Pakitza, USNM 302789, 3; USNM 302787, 4. Provincia Manu, Parque Nacional Manu, Pakitza, Quebrada Pachija (approximately 11°57', 71°17'W), USNM 326818, 5. Provincia Manu, Rio Manu, approximately 2 hours by boat upstream from Boca Manu, USNM 303064, 2. Provincia Manu, Boca Panahua, where Quebrada Panahua en- ters Rio Manu, USNM 302790, 1. Provincia Manu, Rio Manu, approximately 3 hours upriver by boat from Romero, USNM 302784, 3. Provincia Manu, cocha off Rio Alto Madre de Dios, 2 km below Erika (latter locality at approximately 12°53'S, 71°12'W), USNM 302786,2. Provincia Manu, Rio Alto Madre de Dios, 15 km upstream from Boca Manu (12°19'30"S, 70°58'W), ANSP 143768, 1. Ucayali: Provincia Purus, Rio Curanja basin, Caserio Grau (9°58'S, 71°02'W), MUSM 9986, 2. Provincia Purus, Rio Purus (9°50'S, 70°55'W), MUSM 10440, 6. Provincia Purus, Esperanza, Quebrada Esperancillo (9°42'S, 70°40'W), MUSM 10032, 15. Atalaya, Sepahua, Que- brada Shamboyacu, USNM 358016, 13. Atalaya, Sepahua, Nuevo Horizonte, Rio Bajo Urubamba, USNM 358017,21. BRAZIL. Acre: Rio Acre between Seringal Paraiso and Lago Amapa, MZUSP 49760,2. Municipio de Rio Branco, Rio Acre, Coloacao do Chale, 6 hours below Rio Branco (latter lo- cality at 9°58'S, 67°48'W), MZUSP 49625, 5. Amazonas: Rio Acre, Seringal Floresta, 10 minutes above Boca do Acre (latter locality at 8°45'S, 67°23'W), MZUSP 49600,44. Rio Purus, at mouth of Rio Acre (8°45'S, 67°23'W), MZUSP 49708, 10. Municipio de Porto Acre, Rio Acre, Seringal Bom Destino, 1 hour above Porto Acre (latter locality at 9°34'S, 67°31'W), MZUSP 49688,7. Creagrutus ortegai, new species FIGURES 67,71, TABLE 41 DIAGNOSIS.—The combination of the possession of premax- illary dentition arranged in the three components generalized for most of the species of Creagrutus and Piabina without a distinctly larger gap between the first and second teeth of the primary series, 3 or 4 teeth on the maxilla, 6, less commonly 5, teeth in the primary tooth row of the premaxilla, 6 dentary teeth, 37 to 39 lateral line scales without a lamellar process over each pore, 11 or 12 predorsal median scales, 4 or 5 scale rows between the dorsal-fin origin and the lateral line, 36 to 38 TABLE 41.—Morphometrics and meristics of Creagrutus ortegai, new species; (A) holotype of C. ortegai. MUSM 7498; and (B) paratypes of C. ortegai (n= 39). Standard length is expressed in mm; measurements 1 to 14=percentages of standard length; IS to 18=percentages of head length. Characters Standard length 1. Snout to anal-fin origin 2. Snout to pelvic-fin insertion 3. Snout to pectoral-fin insertion 4. Snout to dorsal-fin origin S. Dorsal-fin origin to hypural joint 6. Dorsal-fin origin to anal-fin origin 7. Dorsal-fin origin to pelvic-fin insertion 8. Dorsal-fin origin to pectoral-fin insertion 9. Caudal peduncle depth 10. Pectoral-fin length 11. Pelvic-fin length 12. Dorsal-fm length 13. Anal-fin length 14. Head length IS. Postorbital head length 16. Snout length 17. Bony orbital diameter 18. lnterorbital width Lateral line scales Scale rows between dorsal-fin origin and lateral line Scale rows between anal-fin origin and lateral line Predorsal median scales Branched dorsal-fm rays Branched anal-fin rays Branched pelvic-fin rays Pectoral-fin rays Vertebrae A B Morphometrics 66.5 63.2 47.6 24.5 48.1 55.6 32.0 28.4 33.9 13.2 20.5 15.8 22.0 19.0 26.0 47.9 28.9 30.6 30.6 28.0-71.1 61.0-65.1 44.4--48.S 22.0-25.1 46.4-^*9.7 54.7-59.4 29.4-34.7 25.1-28.0 31.7-33.8 11.5-13.7 19.1-20.7 14.9-17.9 21.7-24.8 17.9-19.1 24.1-27.3 44.4-48.8 24.2-29.1 28.8-33.3 28.3-31.6 Meristics 38 4 3 11 8 10 6 13 38 37-39 4-5 3 11-12 7-81 9-12 5-62 12-14 36-38 'Seven branched dorsal-fin rays present in only 1 of 39 paratypes. 2Five branched pelvic-fin rays present in only 1 of 39 paratypes. vertebrae, 9 to 12 branched anal-fin rays, 2 post-anal median scales to the anal-fin origin, 9 to 11 gill rakers on the lower limb of the first gill arch, the postorbital head length (44.4%-^8.8% of HL), the snout length (24.2%-29.1% of HL), the bony orbital diameter (28.8%-33.3% of HL), the interor- bital width (28.3%-31.6% of HL), the moderately developed third infraorbital with its ventral margin approaching or con- tacting the horizontal limb of the preopercle, the lack of a se- ries of dark midlateral spots on the body, the presence of a rhomboidal humeral mark centered above the lateral line with- out an associated, slightly more dorsally located, secondary pigment mark, the lack of a distinct spot of pigmentation on the basal portions of the middle caudal-fin rays, and the absence of a discrete patch of dark pigmentation on the middle portion of the anterior dorsal-fin rays distinguishes Creagrutus ortegai within the clade composed of Creagrutus and Piabina. DESCRIPTION.—Morphometric and meristic data for Crea- grutus ortegai in Table 41. Head and body relatively robust, more so in specimens larger than 30 mm SL. Greatest body NUMBER 613 171 FIGURE 71.—Creagrutus ortegai, new species, holotype, MUSM 7498, 66.5 mm SL; Peni, San Martin, Provin- cia San Martin, Banda de Shilcayo, upper portions of Quebrada Choclin, tributary to Rio Huallaga, near Shapaja (latter locality is at 6°36'S, 76°16'W). depth at dorsal-fin origin in specimens of approximately 30 mm SL, located at that point or shifted variably anteriorly in larger individuals, and lying approximately midway between dorsal- fin origin and tip of supraoccipital spine in some of largest ex- amined specimens. Dorsal profile of head distinctly convex from margin of upper lip to vertical through posterior nostril in all specimens larger than 30 mm SL, straight from that point to rear of supraoccipital spine in smaller individuals, slightly con- vex in that region in larger specimens. Dorsal profile of body convex from rear of supraoccipital spine to dorsal-fin origin, convexity more pronounced in larger specimens; profile angled at dorsal-fin base. Ventral profile of head and body typically smoothly rounded from tip of lower jaw to pelvic-fin insertion. Obtuse angle at anteroventral corner of dentary found in many Creagrutus species either absent, or barely evident. Prepelvic region of body broadly rounded transversely. Head obtusely rounded in lateral view and more compressed in dorsal view. Upper jaw distinctly longer than, and overhang- ing, lower jaw. Anterior portion of snout fleshy, with scattered papillae; papillae more concentrated on fleshy upper lip, albeit with papillae less well developed than in many congeners. Lower lip fleshy anteriorly, with numerous papillae on dorsal margin and anterior surface. Infraorbital series moderately developed, ventral margin of third infraorbital approaching horizontal limb of preopercle in smaller specimens, ventrally in contact with preopercle in larger individuals. Posterior margins of third through fifth in- fraorbitals distinctly separated from vertical limb of preopercle. Premaxillary dentition in three series: primary row slightly curved, typically consisting of 6 teeth, although only 5 teeth present in about 5% of examined specimens, without pro- nounced gap between first and second tooth of series; triangu- lar cluster of 3 larger teeth; and single tooth of form similar to that of primary series located lateral to fourth tooth of primary premaxillary series, or sometimes lateral to area of contact of third and fourth teeth of primary series. Maxilla with 3, or rarely 4, tricuspidate teeth. Dentary with 6 tricuspidate teeth; first and second teeth distinctly larger than other teeth, sub- equal, approximately 1.7 times height of third tooth; fourth through sixth teeth much smaller and compressed. Dorsal-fin rays typically ii,8, iii,8 in one specimen, ii,7 in one specimen. Dorsal-fin origin located approximately at verti- cal through pelvic-fin insertion. Profile of distal margin of dor- sal fin slightly concave in all specimens larger than 30 mm SL. Anal-fin rays ii,9-12, both 9 and 12 branched rays rare. Hooks typically present on anal-fin rays in mature males of many Cre- agrutus species not present in examined specimens. Profile of distal margin of anal fin with slight anterior lobe and distinctly concave distal margin. Pectoral-fin rays i,11-13. Tip of pecto- ral fin extending posteriorly approximately three-fourths of distance to pelvic-fin insertion. Pelvic-fin rays typically i,6,i, i,5,i in one specimen. Tip of pelvic fin extending posteriorly to anal-fin origin. Hooks typically present on pelvic-fin rays in mature males of many Creagrutus species not present in exam- ined specimens. Gill rakers 6-7 + 9-11. COLORATION IN ALCOHOL.—More recently collected speci- mens retaining guanine on scales and head with silvery head and body. Guanine on body somewhat masking dark midlateral body stripe and humeral mark. Ground coloration yellow in rel- atively recently collected specimens not retaining guanine on body. Specimens preserved in alcohol for longer periods light brown. Dorsal surface of head with dense field of dark chro- matophores; chromatophore field not as pronounced on dorsal surface of snout, particularly in smaller individuals, and fading out along anterior margin of upper lip. Denser crescent-shaped patch of dark pigmentation present immediately anterior to nares. Curved band of dark pigmentation extending from pos- teroventral portion of pigmented region anterior to nares to around ventral and posterior margins of orbit, band widest an- 172 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY teroventral to orbit. Region of head posterior to orbit with scat- tered, dark chromatophores on infraorbitals and opercle; pig- mentation somewhat more concentrated on opercle in many specimens. Scales of dorsal portion of body with dark chromatophores concentrated over center of exposed portion and along poste- rior margin of scales; these more highly pigmented regions on each scale separated by hyaline arch. Pigmentation on scales less prominent on dorsolateral portion of body. Dark humeral mark apparent in all examined specimens. Mark with densely pigmented middle region centered above lateral line at all available body sizes. Less heavily pigmented, variably shaped extensions continue dorsally and ventrally from main body of mark. Midlateral body stripe consisting of deep-lying and dark surface pigmentation. Stripe relatively darkest posteriorly and becoming more diffuse anteriorly. Stripe not obvious anterior to vertical through dorsal-fin origin in specimens less than 40 mm SL, denser and more elongate horizontally in larger indi- viduals with stripe extending anteriorly to posterior margin of humeral mark. Dorsal fin with membranes and fin-ray margins covered with small dark chromatophores, particularly on distal two-thirds of rays; intensity of pigmentation increasing ontogenetically, with number of rays bearing such pigmentation also increasing with body size, albeit not forming black spot even in largest speci- mens. Central portions of anal-fin rays overlain with dark chro- matophores, forming faint longitudinal stripe along fin. Caudal fin with midlateral stripe along body extending very slightly onto extreme basal portion of middle caudal-fin rays. Caudal- fin rays and membranes overlain by dark chromatophores. Pec- toral and pelvic fins hyaline. ETYMOLOGY.—The specific name, ortegai, in honor of our colleague and co-author in other papers, Hernan Ortega of the Museu de Historia Natural, Lima Peru, who collected nearly all known specimens of the species and in recognition of his many contributions to our knowledge of Peruvian freshwater fishes. ECOLOGY.—At the end of the dry season, the type locality of Creagrutus ortegai is a clear water, moderately swiftly flowing stream about 3 m wide and 40-60 cm deep, with a substrate of stones, pebbles, sand, and debris, with dense vegetation along its banks, and a water temperature of approximately 20-22°C (H. Ortega, pers. comm., 1996). During the rainy season the water volume and flow increase significantly with increased sediment load, making it a white-water stream. The Quebrada Ahuashiyacu, from which some paratypes originated, is slightly larger than, but otherwise similar to, the holotype lo- cality. The Rio Cumbaza, another site of origin for some of the paratype series, is significantly larger than the other type local- ities, being approximately 25 to 30 m wide during the dry sea- son, but with conditions otherwise comparable to the holotype locality. Stomach contents of two specimens of Creagrutus ortegai prepared for clearing and staining in this study consisted mostly of insect parts and occasional small intact and chopped- up seeds. DISTRIBUTION.—Creagrutus ortegai is known primarily from the rivers near Tarapoto, Department of San Martin, Peru (Figure 67, filled stars), but the species also occurs further up- stream in the Rio Huallaga basin and in the headwaters of the Rio Aguaytia (see comments under "Remarks," below). REMARKS.—Creagrutus ortegai is the only member of the genus know from the Rio Huallaga valley. Nearly all speci- mens of C. ortegai were collected in the region of Tarapoto, a city in the central portion of that river basin, which is one of the few regions in the Rio Huallaga basin that has been the subject of intense ichthyological sampling efforts. As a consequence, samples are not available to determine the actual range of the species with any certainty. Three lots of the species came from distinctly further upstream within the Huallaga basin in the re- gion of Tingo Maria (AN SP 136832, 136912, 136914). In addi- tion to the samples from the Rio Huallaga basin, three lots (MUSM 2949, 5675, 6572) originated outside of that river sys- tem in the upper reaches of the Rio Aguaytia, a left bank tribu- tary of the Rio Ucayali in the western portions of the Depart- ment of Ucayali. Headwaters of the Rio Aguaytia approach some of the right bank tributaries of the central portions of the Rio Huallaga (see Isbriicker and Nijssen, 1983, fig. 5). One of these lots (MUSM 6572) originated in the Boqueron del Padre Abad, the gap between the Rio Huallaga and Rio Aguaytia ba- sins. The other two lots (MUSM 2949, 5675) were collected in the same general area in the Rio Huacamayo, a right-bank trib- utary of the upper Rio Aguaytia. MATERIAL EXAMINED.—107 specimens (44,28.0-71.1). HOLOTYPE.—PERU. San Martin: Provincia San Martin, Banda de Shilcayo, upper portions of Quebrada Choclin, tribu- tary to Rio Huallaga, near town of Shapaja (latter locality at 6°36'S, 76°16'W), collected by H. Ortega, 15 Nov 1991, MUSM 7498, 1 (66.5). PARATYPES.—39 specimens (39,28.0-71.1). PERU. San Martin: Provincia San Martin, Banda de Shil- cayo, upper portions of Quebrada Choclin, tributary to Rio Huallaga, near town of Shapaja (latter locality at 6°36'S, 76°16 'W), collected with holotype , MUSM 7499, 2 (42.0-49.8); USNM 340969, 2 (44.3-49.3). Provincia San Martin, Tarapoto, Quebrada Ahuashiyacu (approximately 6°30'S, 76°25'W), collected by H. Ortega, 13 Nov 1991, MUSM 7538, 2 (28.9-52.8). Provincia San Martin, Tarapoto, Morales, Rio Cumbaza (6°28'S, 76°28'W), collected by H. Or- tega, 14 Nov 1991, MUSM 7539, 3 (35.4-55.3); MUSM 2948, 1 (45.5). Provincia San Martin, Tarapoto, Rio Shilcayo (ap- proximately 6°30'S, 76°25'W), collected by H. Ortega, 15 Nov 1991, USNM 340970, 3 (42.5-54.0). Provincia San Martin, Tarapoto, stream tributary to Rio Shilcayo (approximately 6°30'S, 76°25'W), collected by H. Ortega, 15 Nov 1991, MUSM 5678, 4 (37.9-64.0); USNM 340971, 4 (35.4-67.0). Provincia San Martin, km 6 along road to Juanjui, Quebrada Pucayacu, collected by H. Ortega and C. Canas, 18 Dec 1994, NUMBER 613 173 MUSM 6571, 2 (39.2-47.5). Provincia San Martin, km 30 along road to Yurimaguas, Rio Cainarachi, collected by H. Or- tega and C. Canas, MUSM 6552, 8 (28.0-71.1); USNM 340972, 8 (29.0-55.0; 2 specimens cleared and counterstained for cartilage and bone). NONTYPE SPECIMENS.—67 specimens (4,42.5-49.8). PERU. San Martin: Provincia San Martin, Rio Ahuashiyacu (6°30'S, 76°25'W), MUSM 1626, 4; MUSM 5676, 4 (2, 49.0-49.8); USNM 340968, 2 (42.5^9.7). Provincia San Mar- tin, Tarapoto, Rio Shilcayo, MUSM 5677, 4. Provincia Lamas, stream tributary to Rio Cainarachi, km 33 on road from Tarapoto to Yurimaguas, MUSM 7540, 3. Provincia Moy- obamba, Puerto Juan Antonio, upper Rio Mayo, MUSM 1631, 6. Huanuco: Provincia Leoncio Prado, vicinity of Tingo Maria, Cueva de Pavos near Puente Perez, approximately 0.15 km above Rio Huallaga (town at 9°19'S, 75°56'W), ANSP 136832, 1; ANSP 136912, 16. Vicinity of Tingo Maria, Rio Monzon ba- sin, Rio Rondos (=Rio Patay Rondos; mouth approximately 9°15'S, 76°05'W), ANSP 136914, 1. Pucallpa: Provincia Pa- dre Abad, Rio Aguaytia, Bogueron del Padre Abad, Velo de Novia, MUSM 6572, 3. Provincia Padre Abad, Aguaytia, Rio Huacamayo, MUSM 2949, 3. Rio Chio, 80 km from Pucallpa on road to Tingo Maria, MUSM 5675, 20. Creagrutus ouranonastes, new species FIGURES 67, 72, TABLE 42 DIAGNOSIS.—The possession of premaxillary dentition with the three components generalized for the species of Creagru- tus, but with a distinct gap between the first and second teeth of primary tooth row and a forward position of the triangular clus- ter of three posteromedial teeth distinguishes C. ouranonastes from all members of the clade formed by Creagrutus and Pia- bina with the exception of Creagrutus maracaiboensis, C. melanzonus, C. muelleri, C. nigrostigmatus, C. peruanus, C. runa, and Piabina argentea. Creagrutus ouranonastes can be distinguished from these seven species by the combination of 7 dentary teeth, 41 to 45 lateral line scales, 13 to 15 predorsal median scales, 6 scale rows between the dorsal-fin origin and the lateral line, 4 scale rows between the anal-fin origin and the lateral line, 40 to 43 vertebrae, 10 or 11 branched anal-fin rays, the distance from the snout to the anal-fin origin (62.7%- 65.6% of SL), the caudal peduncle depth (12.4%-14.1% of SL), the bony orbital diameter (25.7%-29.4% of HL), and the possession of two small, discrete spots of dark pigmentation on the basal portions of the middle caudal-fin rays, a pigmentation pattern that is an autapomorphy for the species. DESCRIPTION.—Morphometric and meristic data for Crea- grutus ouranonastes in Table 42. Head and body quite robust, increasingly so in larger specimens. Greatest body depth at ver- tical through dorsal-fin origin in smaller specimens, shifting distinctly anterior of that point in larger, more robust individu- als (e.g., holotype, Figure 72). Dorsal profile of head distinctly convex from margin of upper lip to vertical through posterior TABLE 42.—Morphometrics and meristics of Creagrutus ouranonastes. new species: (A) holotype of C. ouranonastes, MUSM 8872; and (B) paratypes of C. ouranonastes (n=24). Standard length is expressed in mm; measurements 1 to 14=percentages of standard length; 15 to 18=percentages of head length. Characters Standard length 1. Snout to anal-fin origin 2. Snout to pelvic-fin insertion 3. Snout to pectoral-fin insertion 4. Snout to dorsal-fin origin 5. Dorsal-fin origin to hypural joint 6. Dorsal-fin origin to anal-fin origin 7. Dorsal-fin origin to pelvic-fin insertion 8. Dorsal-fin origin to pectoral-fin insertion 9. Caudal peduncle depth 10. Pectoral-fin length 11. Pelvic-fin length 12. Dorsal-fm length 13. Anal-fin length 14. Head length 15. Postorbital head length 16. Snout length 17. Bony orbital diameter 18. Interorbital width Lateral line scales Scale rows between dorsal-fm origin and lateral line Scale rows between anal-fin origin and lateral line Predorsal median scales Branched dorsal-fin rays Branched anal-fin rays Branched pelvic-fin rays Pectoral-fin rays Vertebrae A B Morphometrics 100.1 62.4 46.2 22.2 48.7 56.0 31.7 28.2 36.0 13.4 20.5 15.3 21.3 18.6 23.8 52.1 28.2 27.3 34.8 38.2-91.2 62.7-65.6 45.4-49.6 21.5-25.3 46.4-51.4 52.1-57.9 27.4-32.3 25.6-30.0 33.3-37.2 12.4-14.1 20.0-21.0 14.9-16.7 20.6-23.6 15.7-18.7 22.7-25.9 46.7-54.5 24.0-29.0 25.7-29.4 30.0-35.7 Meristics 45 6 4 14 8 10 7 12 42 41^*5 6 4 13-15 8 10-11 6-7 13-14 40-43 margin of posterior nares, nearly straight from that point to rear of head in specimens of all sizes. Dorsal profile of body smoothly continuous with profile of head in smaller individu- als, more convex with distinct change in slope relative to align- ment of dorsal profile of head in larger specimens; nearly straight from dorsal-fin origin to caudal peduncle in specimens of all sizes. Ventral profile of head somewhat more convex at anteroventral corner of dentary or somewhat posterior of that point, nearly straight from convex region to rear of isthmus. Ventral profile of body gently convex in smaller individuals, convexity more pronounced in larger specimens. Head obtusely pointed in both lateral and dorsal views. Upper jaw slightly longer than, and overhanging, lower jaw. Anterior of snout only slightly fleshy compared to many congeners, with papillae only obvious along anteromedial portion of snout, along margin of upper lip and on folds and plicae extending between outer and medial premaxillary teeth. Lower lip relatively fleshy anteriorly, with numerous papillae on dorsal surface of lip. Infraorbital series moderately developed, without notable variation in degree of development across available body size range. Ventral margin of third infraorbital falling distinctly 174 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY FIGURE 72.—Creagrutus ouranonastes, new species, holotype, MUSM 8872, 100.1 mm SL; Peru, Apurimac, Aymaraes, Rio Chalhuanca (approximately 14°01'S, 73°1 fW). short of horizontal limb of preopercle. Posterior margins of third through fifth infraorbitals falling distinctly short of verti- cal limb of preopercle. Premaxillary dentition in three series: primary row curved, consisting of 6, rarely 5, teeth, with distinct gap between first and second tooth in row, and between medial teeth of contralat- eral series; triangular cluster of three teeth with anterior tooth approximately same size as teeth of primary row and slightly medial to pronounced gap between first and second teeth of primary row, two other teeth of triangular cluster, particularly posteromedial tooth larger than remaining teeth in jaw; and sin- gle tooth of form similar to that of primary series lying lateral to fourth tooth of primary premaxillary tooth row. Maxilla with 3 or 4 tricuspidate teeth. Dentary with 7 teeth; first and second teeth distinctly larger than others, subequal and tricuspidate; third tooth tricuspidate, about two-thirds height of second tooth; fourth through seventh teeth unicuspidate, distinctly smaller than third tooth, and gradually decreasing in size poste- riorly. Dorsal-fin rays ii,8. Dorsal-fin origin slightly behind vertical though pelvic-fin insertion. Profile of distal margin of dorsal fin slightly concave. Anal-fin rays ii, 10— 11. Profile of distal margin of anal fin distinctively concave. Hooks typically present on anal-fin rays in mature males of many Creagrutus species not present in examined specimens. Pectoral-fin rays i, 11-13. Tip of pectoral fin extending posteriorly slightly more than three-fourths of distance to vertical through pelvic-fin in- sertion. Pelvic-fin rays i,6,i in smaller examined specimens, i,7 in larger individuals. Hooks typically present on pelvic-fin rays in mature males of many Creagrutus species not found in ex- amined specimens. Tip of pelvic fin falling distinctly short of anal-fin origin. Gill rakers 7-8+10-11. COLORATION IN ALCOHOL.—Overall coloration of head and body relatively dark other than in specimens less than 30 mm SL. Dorsal surface of head with dense field of small, dark, stel- late chromatophores. Chromatophore field extending over snout, upper lip, and continuing posteriorly under and posterior to orbit. No intense patch of crescent-shaped pigmentation an- terior to nares as present in many other Creagrutus species. Pigmentation ventral and posterior of orbit not forming discrete band present in many congeners. Pigmented regions on head becoming progressively more intense in larger specimens. Pig- mentation on infraorbitals posterior of orbit concentrated into dark irregular spots in some individuals. Deep-lying patch of dark pigmentation located medial to posterior portion of fifth infraorbital and central portion of opercle; pigmentation in lat- ter region more intense in larger specimens and forming dis- tinct patch of dark coloration on opercle. Dorsolateral surface of body with scale margins marked by bands of dark pigmentation forming overall reticulate pattern. Humeral mark vertically elongate, overall form that of inverted comma; particularly dark portion of humeral mark located im- mediately dorsal of lateral line, and less intensely pigmented curved portion of mark extending anterodorsally from that re- gion for distance of about two scales. Midlateral dark pigmen- tation on body composed of two components: deep-lying band of chromatophores extending somewhat obliquely from behind humeral mark to center of caudal peduncle and narrower, irreg- ular band of darker surface pigmentation. Dorsal fin with small dark chromatophores on rays and membranes, particularly on anterior rays and distal portions of middle dorsal-fin rays. Anal fin with scattered, dark chromato- phores on rays and membranes. Caudal fin with dark chromato- phores outlining rays. Basal portion of middle rays of caudal fin flanked by two discrete, horizontally elongate patches of particularly dark pigmentation. Pectoral and pelvic fins with scattered, dark chromatophores on membranes. ETYMOLOGY.—The specific name, ouranonastes, from the Greek, ouranos, heaven or sky, and nastes, inhabitant, refers to the relatively high elevation localities where the species has been collected. NUMBER 613 175 ECOLOGY.—Nothing is known about the life history of Crea- grutus ouranonastes, but it is found at a notable elevation for a Creagrutus species. Some of the localities at which specimens were collected are at approximately 1900 m altitude, the great- est elevation recorded for any member of the genus. Stomach contents of the single specimen prepared for clear- ing and counter staining consisted of parts of larval insects. DISTRIBUTION.—Creagrutus ouranonastes is known only from the uplands of the Rio Apurimac basin in the southern highlands of Peru (Figure 67, open star) where it is the only member of the genus collected to date. MATERIAL EXAMINED.—25 specimens (25,38.2-100.1). HOLOTYPE.—PERU. Apurimac: Provincia Aymaraes, Rio Chalhuanca (approximately 14°01'S, 73°1 l'W), collected by E. Estacio, 25 Dec 1989, MUSM 8872, 1 (100.1). PARATYPES.—24 specimens (24, 38.2-91.2). PERU. Apurimac: Provincia Aymaraes, Rio Chalhuanca (approximately 14°01'S, 73°11'W), collected with holotype, USNM 340989, 1 (91.2). Provincia Abancay, Hacienda Mat- ara, Quebrada Matara, Rio Matara system (mouth of river at 13°44'S, 72°55'W), 6200 ft (=1890 m) elevation, collected by C. Sanborn, Dec 1941, FMNH 41801, 14 (38.2-86.1). Cusco: Provincia Anta, Rio Apurimac, Conocc (13°33'S, 72°37'W), collected by E. Estacio, 9 Nov 1992, MUSM 6574, 5 (41.8-82.0); USNM 340988, 4 (57.2-84.6; 1 specimen cleared and counterstained for cartilage and bone). Creagrutus paraguayensis Mahnert and Gery, 1988 FIGURES 73, 74, TABLE 43 Creagrutus paraguayensis Mahnert and Gery, 1988:5, figs. 4, 5, pi. 3 [type lo- cality: Rio Azotey a Cororo pres de l'embouche du Rio Ypane, prov. Concep- cion, Paraguay (= Paraguay, Conception Province, Rio Azotey at Cororo, near mouth of Rio Ypane)]. DIAGNOSIS.—The combination of the possession of premax- illary dentition arranged in the three components generalized for most of the species of Creagrutus and Piabina without a distinctly larger gap between the first and second teeth of the primary series, 2 or 3 teeth on the maxilla, 6, less commonly 5, teeth in the primary tooth row of the premaxilla, 5 or 6 dentary teeth, 37 to 41 lateral line scales without a lamellar process over each pore, 11 to 13 predorsal median scales, 5 scale rows between the dorsal-fin origin and the lateral line, 37 to 39 ver- tebrae, 13 to 15 branched anal-fin rays, 2 post-anal median scales to the anal-fin origin, the distance from the snout to the anal-fin origin (55.3%-61.0% of SL), the distance from the snout to the dorsal-fin origin (47.2%-51.8% of SL), the dis- tance from the dorsal-fin origin to the anal-fin origin (28.2%-33.8% of SL), the distance from the dorsal-fin origin to the hypural joint (52.5%-57.8% of SL), the distance from the dorsal-fin origin to the pectoral-fin insertion (32.8%-38.3% of SL), the anal-fin length (17.6%-20.7% of SL), the interor- bital width (32.0%-38.8% of HL), the lack of a series of dark midlateral spots on the body, the moderately developed third infraorbital with its ventral margin falling distinctly short of the TABLE 43.—Morphometrics and meristics of Creagrutus paraguayensis: (A) holotype of C. paraguayensis, MHNG 2386.1; and (B) all other specimens of C. paraguayensis from which counts and measurements were taken (n=29). Standard length is expressed in mm; measurements 1 to 14=percentages of standard length; IS to 18=percentages of head length. Characters Standard length 1. Snout to anal-fin origin 2. Snout to pelvic-fin insertion 3. Snout to pectoral-fin insertion 4. Snout to dorsal-fin origin 5. Dorsal-fin origin to hypural joint 6. Dorsal-fin origin to anal-fin origin 7. Dorsal-fin origin to pelvic-fin insertion 8. Dorsal-fin origin to pectoral-fin insertion 9. Caudal peduncle depth 10. Pectoral-fin length 11. Pelvic-fin length 12. Dorsal-fin length 13. Anal-fin length 14. Head length 15. Postorbital head length 16. Snout length 17. Bony orbital diameter 18. Interorbital width Lateral line scales Scale rows between dorsal-fin origin and lateral line Scale rows between anal-fin origin and lateral line Predorsal median scales Branched dorsal-fin rays Branched anal-fin rays Branched pelvic-fin rays Pectoral-fin rays Vertebrae A B Morphometrics 32.9 58.7 43.5 23.7 49.0 53.8 28.7 26.5 33.4 12.2 20.7 15.2 24.0 20.4 24.6 45.2 30.0 35.8 34.6 30.1-57.5 55.3-61.0 42.6-^6.8 22.8-25.1 47.2-51.8 52.5-57.8 28.2-33.8 26.4-31.7 32.8-38.3 10.5-12.5 19.5-22.3 15.0-17.7 21.9-24.8 17.6-20.7 23.0-26.7 37.3-^5.7 26.3-30.1 31.5-37.6 32.0-38.8 Meristics 38 5 4 13 8 15 6 12 39 37-41 5 3-4 11-13 8 13-15 6-7 11-13 37-39 horizontal limb of the preopercle, the vertically elongate hu- meral mark, and the absence of a discrete patch of dark pig- mentation on the middle portion of the anterior dorsal-fin rays distinguishes Creagrutus paraguayensis within the clade com- posed of Creagrutus and Piabina. DESCRIPTION.—Morphometric and meristic data for Crea- grutus paraguayensis in Table 43. Overall form of head and body moderately elongate in smaller individuals up to approxi- mately 35 mm SL, becoming relatively deeper ontogenetically, with larger examined individuals having proportionately deeper bodies than majority of congeners. Greatest body depth at dorsal-fin origin in smaller individuals and at, or slightly an- terior to, that point in larger specimens. Dorsal profile of head distinctly convex anteriorly from margin of upper lip posteri- orly to approximately vertical through anterior margin of ante- rior nares; straight to slightly convex from that point to rear of supraoccipital spine. Predorsal profile of body slightly convex and smoothly continuous with that of head in smaller speci- mens, somewhat more convex, with associated change in align- ment of dorsal profile of body relative to that of rear of head in 176 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY FIGURE 73.—Creagrutus paraguayensis. UMMZ 206266, 57.2 mm SL; Paraguay, Caaguazu, Arroyo Tapiracuai (tributary to Arroyo Tabatiry, Rio Manduvira basin) at boundary between Departamento Caaguazu and Departa- mento San Pedro, 17.7 km ENE of Mbutuy (23°53'24"S, 56°09'0 65°57'W), collected by B. Chemoff et al., 21 Mar 1987, ANSP 161238, 1 (38.5). PARATYPES.—18 specimens (16, 25.4-39.8). VENEZUELA. Amazonas: Rio Casiquiare from mouth of Rio Pamoni to 4 km below mouth (02°48'N, 65°57'W), collected by B. Chernoff et al., 17 Mar 1987, ANSP 161236, 10 (25.4-39.8). Rio Orinoco at sand playa just upstream from Quiratare (02°59'N, 66°04'W), collected by B. Chernoff et al., 10 Mar 1987, ANSP 161237, 6 (25.7-32.5). Rio Casiquiare main channel, near Rio Orinoco confluence, ANSP 177829, 2. Genus Piabina Reinhardt, 1867 Piabina Reinhardt, 1867:49 [type species Piabina argentea Reinhardt, 1867:50, by monotypy. Gender feminine; volume dated 1866 but actual date of publication was 1867 according to Nielsen, 1974:45, 112].—Eigenmann and Eigenmann, 1891:56 [Piabina placed as a synonym of Creagrutus Giinther].—Eigenmann, 1910:435 [Piabina resurrected from synonymy of Creagrutus].—Mahnert and Gery, 1988:7 [Piabina returned to the synonymy of Creagrutus]. DIAGNOSIS.—Piabina is phylogenetically diagnosed by the possession of the synapomorphies listed under "Monophyly of Piabina," above. Piabina is externally distinguished within the clade formed by Piabina and Creagrutus by the posteriorly at- tenuating, triangular fourth infraorbital, which is excluded in larger specimens of the genus from the posterior margin of the infraorbital series as a consequence of the contact of the proxi- mate posterior portions of the third and fifth infraorbitals. REMARKS.—Reinhardt's description of Piabina (1867:49) followed soon after Giinther's (1864:339) paper proposing Creagrutus. Reinhardt (1867) did not cite Gunther's genus, Creagrutus, and in light of the relatively brief interval between the publication of the two papers, Reinhardt may have been un- aware of Gunther's paper. Alternately, the relatively brief, and somewhat confusing, description of the premaxillary dentition in Creagrutus provided by Giinther may have made it difficult for Reinhardt to recognize the similarity between the two nom- inal genera. Regardless of the cause, the original description of Piabina did not distinguish that genus from Creagrutus, nor did Liitken (1875:224) address that question in his subsequent publication dealing with Piabina. Eigenmann and Eigenmann (1891:56) first noted the similar- ity of the two genera by placing Piabina into the synonymy of Creagrutus, albeit without commenting on the basis for their action. Eigenmann (1910:435) resurrected Piabina from the synonymy of Creagrutus, but neither commented on this rever- sal of the previous synonymy of these genera by Eigenmann and Eigenmann (1891) nor identified the features that he con- sidered served to distinguish the two genera. In their descrip- tion of Piabina analis, a species subsequently transferred to Pi- abarchus (Myers, 1928:90), Eigenmann et al. (1914:8) noted that the species had a "mouth as in Creagrutus" and that the species had the "anal long" presumably identifying the differ- ence in the length of the anal fin (= number of anal-fin rays) as distinguishing Piabina from Creagrutus. Although not com- menting on the diagnostic features for Piabina, Pearson (1924:45) described a second species, P. beni (=Creagrutus pearsoni of this paper), which also was characterized by a rela- tively high number of anal-fin rays in comparison to most members of the Creagrutus-Piabina clade. The number of anal-fin rays was explicitly put forward by Eigenmann (1927:429) as diagnostic for Piabina versus Creagrutus. In their description of Creagrutus paraguayensis Mahnert and Gery (1988:7) noted that the number of anal-fin rays in the 224 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY two nominal genera failed to separate Piabina from Creagrutus when all species in the two genera were considered. Those au- thors consequently returned Piabina to the synonymy of Crea- grutus. Those authors did not explore the phylogenetic rela- tionships of Piabina within such a more inclusive Creagrutus. Our analysis of information from a series of body systems has shown that Piabina argentea, the type species of that ge- nus, forms the sister group to Creagrutus rather than constitut- ing a clade within the latter genus, or even being closely related phylogenetically to the species of Creagrutus (in the sense of this study), which also have relatively high anal-fin ray counts. Creagrutus, in turn, is defined by a large series of derived fea- tures unique in some cases to that genus among characiforms. We recognize Piabina as distinct from Creagrutus to highlight the differences between the clades, and we use the generic- level taxonomy as a vehicle to reflect the sister-group relation- ship between these taxa. As noted above, Eigenmann et al. (1914:8) added a second species to Piabina with their description off! analis, a species subsequently transferred to Piabarchus (Myers, 1928:90). Al- though the phylogenetic relationships of Piabarchus remain unresolved, the genus lacks the synapomorphies for Piabina and for the clade formed by Piabina plus Creagrutus. Piabina analis of Eigenmann et al. (1914:8) is consequently not in- cluded in this study. The third nominal species originally described in Piabina is P. beni (the Creagrutus pearsoni of this paper), which was de- scribed by Pearson (1924:45). The available evidence indicates that this is a member of the Creagrutus clade as defined by a series of derived features rather than being closely aligned phy- logenetically with Piabina. Piabina argentea Reinhardt, 1867 FIGURES 90,95-97, TABLE 60 Piabina argentea Reinhardt, 1867:50, pi. 1: figs. I, 2 [Brazil (Minas Gerais), Lagoa Santa].—Lutken, 1874:141 [Brazil (Minas Gerais), Rio das Velhas]; 1875:226, fig. [Brazil (Minas Gerais), Rio das Velhas].—Eigenmann, 1910:434 [Brazil (Minas Gerais), Rio das Velhas basin].—Eigenmann and Myers, 1929:430, pi. 35: figs. 3-3a; pi. 97: fig. 9 [Brazil (Bahia), Rio San (= Sao) Francisco, Rio Itapicum, upper (Rio) Parana].—Amaral-Campos, 1945:433, fig. 2 [Brazil, Sao Paulo, Rio Mogi-Guacu].—Fowler, 1948:162 [literature summary].—Gomes and Monteiro, 1955:105-106 [Brazil, Sao Paulo, Pirassununga].—Travassos, 1960:27 [Brazil, Rio Sao Francisco; com- mon name].—Gomes and Azevedo, 1960:136 [Brazil, Sao Paulo, Rio Ca- manducaia, Monte Algre do Sul].—Britski, 1972:87 [Brazil, Sao Paulo, upper Rio Parana].—Nielsen, 1974:45 [depository of syntypes].—de Godoy, 1975:122 [Brazil, Sao Paulo: Rio Mogi Guassu, Cachoeira de Emas; life his- tory].—Ringuelet, 1975:58 [Rio Parana basin].—Britski et al., 1984:44, 109, fig. 30 [Brazil, Minas Gerais, Sao Francisco basin, Tres Marias].—Britski et al., 1986:20, 44, 96, fig. 30 [Brazil, Minas Gerais, Sao Francisco basin, Tres Marias].—Mahnert and Gery, 1988:5 [synonymy of Piabina (including P. ar- gentea) into Creagrutus].—Barrella and Petrere, 1994:164 (Brazil, Sao Pau- lo, Rio Tiete basin, Rio Jacare Pepira].—Araujo, 1996:16 [Brazil, Rio de Jan- eiro, Rio Paraiba do Sul].—Evers, 1997:11, unnumbered fig. on p. 8 [Brazil, Minas Gerais].—Agostinho et al., 1997:184 [Brazil, upper Rio Parana ba- sin].—Alves and Vono, 1999:36 [Brazil, Minas Gerais, Rio Parapeba]. Creagrutus argentea.—Eigenmann and Eigenmann, 1891:56 [Brazil, Minas Gerais, Rio das Velhas; species shifted from Piabina to Creagrutus].—Mah- nert and Gery, 1988:5 [synonymy of Piabina. including P. argentea. into Cre- agrutus]. Piabina piquira.—Eigenmann, 1910:434 [Brazil (Sao Paulo), Piracicaba; nomen nudum in listing of species].—Eigenmann and Myers 1929:430 [list- ed as synonym of Piabina argentea].—de Godoy, 1975:122 [in synonymy of Piabina argentea]. DIAGNOSIS.—Piabina argentea is unique within the Crea- grutus-Piabina clade in the possession of a posteriorly tapering fourth infraorbital, which in adults is excluded posteriorly from the posterior margin of the infraorbital ring by the contact of the proximate posterior portions of the third and fifth infraor- bitals. In addition to that autapomorphic feature, the possession of the form of premaxillary dentition with the three compo- nents generalized for the species of Creagrutus and Piabina, but with a distinct gap between the first and second teeth of the primary tooth row and a forward position of the triangular clus- ter of three posteromedial teeth distinguishes Piabina argentea from all members of the clade formed by Creagrutus and Pia- bina with the exception of Creagrutus maracaiboensis, C. melanzonus, C. muelleri, C. nigrostigmatus, C. ouranonastes, C. peruanus, and C. runa. Piabina argentea can be distin- guished from these seven Creagrutus species by the combina- tion of its possession of 4 or 5 rows of scales between the lat- eral line and the dorsal-fin origin, 15 to 18 branched anal-fin rays, 36 to 39 vertebrae, the caudal-peduncle depth (9.0%- 10.9% of SL), and the distance from the dorsal-fin origin to the hypural joint (48.5%-52.7% of SL). DESCRIPTION.—Morphometric and meristic data for the pop- ulations of Piabina argentea in Table 60. Greatest body depth in region between vertical through pelvic-fin insertion and ver- tical through dorsal-fin origin, typically located more anteriorly in ripe females and in both sexes in populations with propor- tionally deeper bodies. Anterior profile of snout distinctly rounded. Dorsal profile of head somewhat variable. At one ex- treme profiles of snout and remainder of head meeting in ob- tuse angle near vertical immediately anterior to nares, whereas at other extreme specimens with smoothly continuous profile between upper lip and tip of supraoccipital spine. Dorsal pro- file of head posterior of vertical through nares and predorsal re- gion of body ranging from nearly straight to noticeably convex. Dorsal profile of body nearly straight between dorsal-fin origin and adipose fin in all populations and not demonstrating change in alignment relative to head profile. Ventral profile of head with distinct, but rounded, obtuse angle delimiting an- teroventral of dentary. Ventral profile of head posterior of that angle and profile of anterior portion of body smoothly convex to pelvic-fin insertion; convexity more pronounced in some rel- atively deep-bodied populations, typically those from lacus- trine habitats. Upper jaw longer than, and overhanging, lower jaw. Anterior surface of snout fleshy, particularly anteroventrally, and cov- ered with minute papillae. Papillae most concentrated on upper lip, margin of upper and lower jaws, and in mouth on fleshy, NUMBER 613 225 TABLE 60.—Morphometrics and meristics of Piabina argentea: (A) lectotype of P. argentea, ZMUC 253; and (B) all specimens of P. argentea from which counts and measurements were taken (n=69). Standard length is expressed in mm; measurements 1 to 14=percentages of standard length; 15 to 18=percent- ages of head length. Dash indicates value for the damaged lectotype that could not be accurately measured. Characters Standard length 1. Snout to anal-fin origin 2. Snout to pelvic-fin insertion 3. Snout to pectoral-fin insertion 4. Snout to dorsal-fin origin 5. Dorsal-fin origin to hypural joint 6. Dorsal-fin origin to anal-fin origin 7. Dorsal-fin origin to pelvic-fin insertion 8. Dorsal-fin origin to pectoral-fin insertion 9. Caudal peduncle depth 10. Pectoral-fin length 11. Pelvic-fin length 12. Dorsal-fin length 13. Anal-fin length 14. Head length 15. Postorbital head length 16. Snout length 17. Bony orbital diameter 18. lnterorbital width Lateral line scales Scale rows between dorsal-fin origin and lateral line Scale rows between anal-fin origin and lateral line Predorsal median scales Branched dorsal-fin rays Branched anal-fin rays Branched pelvic-fin rays Pectoral-fin rays Vertebrae A B Morphometrics 59.2 63.1 46.9 24.8 51.5 52.9 29.4 27.0 35.1 9.4 19.4 14.4 22.8 16.7 26.4 47.1 27.3 32.7 28.2 27.4-68.0 59.0-63.7 44.6-47.3 22.5-27.0 48.5-52.7 48.5-52.7 25.8-30.7 23.4-30.0 32.5-38.3 9.0-10.9 18.6-21.0 14.2-15.9 21.4-25.4 15.6-18.8 24.5-28.3 39.0-47.5 26.8-31.2 29.4-36.2 27.3-33.3 Meristics 40 5 4 12 8 18 6 - 38 39^t2' 4-5 4 11-13 8 15-18 6 12-13 36-39 'Forty-two lateral line scales present in only 1 specimen. plicate folds between premaxillary teeth. Lower lip very fleshy, particularly anteriorly. Infraorbital series well developed. Ventral margin of third in- fraorbital approaching horizontal limb of preopercle; antero- ventral portion of bone sometimes contacting horizontal limb of preopercle in larger specimens. Posterior portion of fourth infraorbital attenuated, barely reaching posterior margin of in- fraorbital ring in smaller individuals, excluded from the poste- rior margin of infraorbital series as consequence of contact of proximate posterior portions of the third and fifth infraorbitals. Posterior margins of third and fifth infraorbitals slightly sepa- rated from vertical limb of preopercle even in larger specimens. Premaxillary dentition in three series: primary series sigmoid with 5 teeth; contralateral medial teeth distinctly separated from each other and somewhat less separated from second tooth of each series, but nonetheless with distinct gap between those teeth; triangular cluster of 3 larger teeth with medial teeth in contact and anterior tooth of triangular cluster partially occu- pying pronounced gap between first and second teeth of main series; and single tooth of form similar to that of primary series lying lateral to fourth tooth of primary series. Maxilla with 2, rarely 3, tricuspidate teeth. Dentary with 6 or 7 teeth; 3 anterior teeth tricuspidate and distinctly larger than other teeth in the se- ries, with first and second teeth subequal in size and larger than third tooth. Remaining dentary teeth gradually decreasing in size posteriorly; either all tricuspidate (when 6 teeth present) or last tooth nearly conical (when 7 teeth present). Dorsal-fin rays ii,8. Dorsal-fin origin located slightly poste- rior to vertical through pelvic-fin insertion. Distal margin of dorsal fin nearly straight. Anal-fin rays iii,15-18. Distal margin of anal fin distinctly concave, with last unbranched and anterior branched rays longest. Single hooks present on last unbranched and anterior 4 to 7 branched anal-fin rays of mature males; hooks restricted to posterolateral surface of main shaft of un- branched ray and posterior secondary branch of branched rays. Pectoral-fin rays i,l 1-12. Tip of pectoral fin extending posteri- orly nearly to pelvic-fin insertion in smaller specimens, falling distinctly short of that point in larger individuals. Pelvic-fin rays i,6,i. Tip of pelvic fin extending posteriorly approximately to anus. Mature males with hooks on all branched pelvic-fin rays; hooks extending from basal unsegmented portion of ray distally onto all but distal portions of rays. Two lateralmost, branched rays with hooks only on medial margin of medial portion of ray, whereas other branched rays with hooks along medial margin of all major branches. Gill rakers 6-7+ 9-11. COLORATION IN LIFE (based on a transparency of a live spec- imen from the Rio Vermelho, Minas Gerais, Brazil, provided by Hans-Georg Evers and published in Evers, 1997).—Overall coloration of head and body silvery. Midlateral portion of body, fin rays, and basal portions of each caudal-fin lobe iridescent. Posterolateral portion of head iridescent dorsally. Eye along with lateral and ventral portions of head silvery. Humeral mark and reticulate pattern on body, particularly on dorsal portion of body, quite obvious. Dark midlateral stripe somewhat masked by overlying guanine deposits. Abdominal region silvery. Oth- erwise dark pigmentation as in preserved specimens (see "Col- oration in Alcohol," following). COLORATION IN ALCOHOL.—Dorsal surface of head with both shallow and deep-lying dark chromatophores. Large stel- late chromatophores on membranes of brain obvious in smaller individuals, but masked by pigmentation on surface of head in larger specimens. Variably dense field of dark chromatophores over dorsal surface of head, snout, and upper lip. Chromato- phores more concentrated in irregular band running from ante- rior of nares posterodorsally along ventral margin of adipose eyelid to near anteroventral margin of eye. Band continued as narrow series of chromatophores around ventral and posterior border of orbit. Dorsal portions of opercle and infraorbitals posterior to orbit with scattered, large chromatophores. Dorsal portion of body with small dark chromatophores con- centrated on posterior portion of scales, forming overall reticu- 226 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY late pattern. Form of humeral mark somewhat variable both on- togenetically and among similar-sized specimens within many population samples. Specimens of approximately 20 mm SL with mark formed by rotund patch of large, dark chromato- phores entirely dorsal of lateral line. Individuals of approxi- mately 40 mm retaining central patch of dense chromato- phores, but often with sparse fields of dark chromatophores extending dorsal and ventral of main pigmentation patch and giving humeral mark overall vertically elongate appearance. Degree of vertical elongation variable, with some individuals having only slightly vertically elongate rotund mark and others with humeral mark approaching form of vertical bar. Speci- mens with distinctly vertically elongate mark, usually with por- tion of chromatophore field dorsal of main body of mark better developed than ventral of main portion of mark. Some individ- uals with ventral portion of mark forming ventrally attenuating bar. Dark midlateral body stripe diffuse anteriorly at all sizes but with distinct dorsal and ventral margins. Stripe limited to cau- dal peduncle and posterior portion of body in specimens of ap- proximately 20 mm SL, stripe extending progressively further anteriorly with increasing body size, and nearly extending to posterior margin of humeral mark in largest examined individ- uals. Dorsal fin with series of small dark chromatophores along margins of distal one-half of anterior rays. Caudal and anal fins with small, dark chromatophores scattered over membranes and delimiting fin-ray margins. Pectoral and pelvic fins either hyaline or with scattered, dark chromatophores. ECOLOGY.—de Godoy (1975:125-126) reported that in the upper Rio Parana basin Piabina argentea matures sexually be- ginning in late September. In the same region, that author re- ports that this species feeds primarily on phytoplankton and various life stages of diverse groups of aquatic insects (Chi- ronomidae, Ephemeroptera, Odonata, Simulidae, and Tri- choptera). Examination of a series of stomach contents during this study revealed primarily insect remains, small intact seeds, chopped-up seeds, and lesser amounts of phytoplankton. COMMON NAME.—Brazil , Rio Sao Francisco: "Piaba" (Travassos, 1960:27); upper Rio Parana: "Piquira" (de Godoy, 1975:122). DISTRIBUTION.—Piabina argentea occurs in the upper Rio Parana basin in northeastern Paraguay and southern Brazil above the Salto de Guaira and in the Rio Sao Francisco, Rio Itapicuru, Rio Paraiba, and Rio Itapemirim basins of eastern Brazil (Figure 90, stars). COMPARISONS.—Piabina argentea is allopatric to the Crea- grutus clade and is readily distinguished from all Creagrutus species by its posteriorly attenuating, triangular fourth infraor- bital, which is excluded from the posterior infraorbital margin in larger specimens by the contact of the proximate posterior portions of the third and fifth infraorbitals. GEOGRAPHIC VARIATION.—Piabina argentea has a unusu- ally broad distribution compared with the members of it sister clade, the species of Creagrutus, ranging from the central por- tions the Rio Parana basin to the area slightly north of the lower portions of the main channel of the Rio Sao Francisco. Al- though different population samples demonstrate modally dif- fering variation in some features, there is, nonetheless, broad overlap between samples of different populations that have similar overall appearance (Figures 96, 97). In light of the de- gree of this overlap, we consider these populations to be con- specific. The most notable feature that varies geographically between the Rio Parana populations and samples from the more northerly portions of the species' range is the number of vertebrae, although this feature has broad overlap between these major river basins. Populations samples from the Rio Parana basin have 36 to 39 vertebrae, with a mean of 37.65 (n= 26), whereas those from the Sao Francisco basin have 37 to 39 vertebrae with a mean of 38.11 (n=53). REMARKS.—Piabina argentea was described by Reinhardt (1867:49), who based the description on specimens collected in Lagoa Santa in the upper Rio Sao Francisco basin of the state of Minas Gerais, Brazil. Two syntypes are known to be extant (Nielsen, 1974: 45). Although the single syntype examined in the course of this study (Figure 95) is in somewhat poor condi- tion, it demonstrates the form of the posterior infraorbitals syn- apomorphic for the genus along with the other features that in combination discriminate Piabina from Creagrutus. This syn- type (ZMUC 253) is designated as the lectotype, and the other syntype (ZMUC 254, not examined in this study) consequently becomes a paralectotype. In his listing of the then-known freshwater fishes of South America, Eigenmann (1910:434) listed Piabina piquira with a stated locality of Piracicaba, in the upper Rio Parana basin of the state of Sao Paulo, Brazil. That species was not, however, ever formally described, and Eigenmann and Myers (1929:430) listed it in the synonymy of Piabina argentea. MATERIAL EXAMINED.—1462 specimens (69, 27.4-68.0). BRAZIL. Bahia: Queimadas, Rio Itapicuru basin (10°58'S, 39°38'W), CAS 70952 (formerly IU 13370), 5. Rio Itapicuru, FMNH 54322 (formerly CM 54322), 6. Rio Verde Pequeno, tributary to Rio Verde Grande, on road between Urandi and Es- pinosa (14°50'44"S, 42°45'36"W), ANSP 171966, 8. Distrito Federal: Ribeirao Santana, at road crossing approximately 30 air km S of Barragem do Paranoa (Rio Bartolomeu of Rio Parana basin; 15°55'S, 47°46'W), USNM 292220, 76 (10, 33.8-65.5; 1 specimen cleared and counterstained). Ribeirao Santana (Rio Parana basin, 16°01'S, 47°49'W), UF 78195, 67 (10, 44.8-61.5). Rio Piripau, near Planaltina (approximately 15°37'S, 47°40'W), MZUSP 28040, 20 (5, 53.2-58.3); MZUSP 48361, 1. Espirito Santo: Rio de Frade e da Freira, Cachoeiro de Itapemirim (20°51'S, 41°06'W), MZUSP 17058, 1. Goids: Goiana, Rio Meia Ponte basin, Ribeirao Joao Leite (16°39'S, 49°16'W), MZUSP 47750, 1. Minas Gerais: Lagoa Santa (19°38'S, 43°53'W), ZMUC 253, 1 (59.2, lectotype of Piabina argentea). Corrego do Jacque, Campinho, near Lagoa Santa, MZUSP 18922, 5. Rio das Velhas, FMNH 54579,6 (for- NUMBER 613 227 FIGURE 95.—Piabina argentea, lectotype, ZMUC 253, 59.2 mm SL; Brazil, Minas Gerais, Lagoa Santa (I9°38'S, 43°53'W). FIGURE 96.—Piabina argentea, MZUSP 38001, 57.4 mm SL; Brazil, Minas Gerais, Rio das Velhas basin, Ribeirao Jaboticatubas (19°26'S, 43°55'W). FIGURE 97.—Piabina argentea. UF 78195, 61.0 mm SL; Brazil, Distrito Federal, Ribeirao Santana (Rio Parana basin, 16°01'S,47°49'W). merly CM 4765). Corrego Chumbo, Rio Abaete basin (approx- imately 18°37'S, 46°12'W), MZUSP 39650, 14. Major Porto, Rio Abaete, Corrego Agua Limpa, MZUSP 39595, 54 (20, 27.4-39.8). Major Porto, Rio Abaete, Corrego Capivara, MZUSP 39625, 21. Corrego Espraiado, Rio Abaete, MZUSP 39681, 7. Rio Sao Francisco, Piraporinha (Buriti), opposite Pi- rapora (17°21'S, 44°56'W), USNM 100955, 3. Piraporinha, corrego tributary to Rio Sao Francisco, UMMZ 216283, 12. Corrego de Juliao, along road to Tabuticatubas and Jabutica- tuba, N of Lagoa Santa, USNM 311172, 10(5,35.6-52.0; 1 228 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY specimen cleared and counterstained for cartilage and bone). Rio das Velhas basin, Ribeirao Jaboticatubas (19°26'S, 43°55'W), MZUSP 38001, 66 (10,44.3-56.3); MZUSP 37944, 23. Tributary to Rio Grande, 1.5 km W of Possos on highway between Possos and Itau de Minas, USNM 342929, 10. Cor- rego do Juliao, along road to Jabuticatuhas (19°23'S, 49°01'W), MZUSP 18925, 22. Sao Joao del Rei, Rio das Mortes, upper Rio Parana basin (21°09'S, 44°16'W), CAS 70953, 3 (formerly 1U 13299, in part); USNM 167822, 1 (for- merly 1U 13299, in part); FMNH 54582, 10 (formerly CM 3767). Riacho dos Pocoes, tributary of Rio Coxa-Rio Carin- hanha, approximately 11 km S of Montalvania (14°31'S, 44°24'W), ANSP 171965, 60. Rio Meleno at Cachoeira de Me- leno, approximately 23 km SE of Felixlandia, Rio Paraopeba drainage (18O51'43"S, 44°45'14"W), ANSP 171963, 14. Rio Pandeiras at the Rio Pandeiras campground, 48 km WSW of Januaria (15°30'43"S, 44°45'12"W), ANSP 171964, 1. Rio Grande basin, Repressa de Camargo, MZUSP 18578, 11. Rio Grande, Repressa de Furnas, Boa Esperanca, MZUSP 18598, 3. Rio Grande, Repressa de Furnas, Alfonas, MZUSP 18575, 131. Rio Jequitai basin, along BR-135 between Buenopolis and Engenheiro Dolabela, MZUSP 47318, 1. Fortaleza de Minas, Riacho tributary to Rio Sao Joao, MZUSP 35394, 23. Fortaleza de Minas, along road from Fortaleza de Minas to Jacui, MZUSP 35384, 28. Ribeirao da Prata, along road from Sao Joao del Rei to Itutinga, MZUSP 17835, 5. Ribeirao tributary to Rio Paraopeba, Municipio de Moeda, MZUSP 37153, 100. Corrego Jenipapo, Rio Sao Francisco basin, MZUSP 39538, 1. Tres Lagoas, Ilha de Mandioca, Rio Sucuriii, MZUSP 16976, 3. Rio Sao Francisco, Tres Marias, MZUSP 17091, 64. Rio Sao Francisco, mouth of Rio Formosa (approximately 17°25'S, 44°58'W), MZUSP 39455, 6. Rio Sao Francisco basin, Rio Formoso, MZUSP 39359, 1. Ribeirao do Gado, tributary of Rio Sao Francisco, MZUSP 39174, 44. Corrego Braco Grande, tributary of Rio Sao Francisco, MZUSP 39227, 1. Pernam- buco: 350 km W of Recife, ZMH 5717, 4. Sao Paulo: Rio Pardo, Barragem de Itaipava, near Santa Rosa de Viterbo (21°25'S, 47°20'W), USNM 302510, 4. Ribeirao da Boiada, Fazenda Santa Carlota, Municipio de Cajuru (21°27'S, 47° 1 4 ^ ) , USNM 322478, 15 (5, 52.7-68.0). Piracicaba, CAS 70951, 2 (formerly IU 11630); FMNH 54584, 1 (formerly CM 3215a). Upper Rio Piracicaba basin, near Jaguariuna, USNM 342928, 10. Rio Corumbatai, Municipio de Corumbatai (22°14'S, 47°38'W), USNM 322095, 10; MZUSP 16756, 66 (3, 49.3-54.2); MZUSP 10745, 50; MZUSP 17034, 2. Corrego de Pinheiro, Corumbatai, MZUSP 16913, 1. Sao Paulo, Ipi- ranga, Rio Tamanduatei, MZUSP 17091, 64. Rio Mogi-Guacu, Emas (21°56'S, 47°22'W), MZUSP 16835, 1; MZUSP 16852, 12; MZUSP 16727, 1; MZUSP 16698, 2. Corrego de Abrigo, Barragem de Jupia (approximately 20°47'S, 51°37'W), MZUSP 17245, 50; MZUSP 17234, 93. Rio Santo Inacio, Par- dinho (23°06'S, 48°23'W), MZUSP 35190, 2. Rio Tiete, Itu, Fazenda Pau D'Alho (approximately 23°16'S, 47°19'W), MZUSP 17313, 1; MZUSP 16775, 5. Rio Tiete basin, Penapo- lis (21°24'S, 50°04'W), MZUSP 35712, 2. Rio Tiete basin, Municipio de Jose Bonifacio (21°03'S, 49°41'W), MZUSP 18457, 26. Campinas, Rio Atibaia, on road from Fortuna near Highway Dom Pedro I, MZUSP 45514, 10; MZUSP 45497, 5; MZUSP 49870, 4. Rio Jaguari, Pereira (22°43'S, 46°55'W), MZUSP 18794, 28. Rio Caligari, Botucatu, MZUSP 39874, 1. Pirassununga, MZUSP 16678, 8. Rio Parana, Ilha Psaltery, MZUSP 17161, 20. Rio de Janeiro: Sao Fidelis, Corrego Pedra D'Aqua (approximately 21 °39'S, 41°44'W), MZUSP 17054, 2. Rio Paraiba, Sao Fidelis, MZUSP 17109, 8. PARAGUAY. Canendiyu: Rio Parana basin, Rio Piratiy, at Balneario Municipal, 1 km S of bridge on road just W of Salto Del Guaira (24°03'S, 54°18'W), UMMZ 206400, 1. Rio Parana basin, Rio Piratiy just below bridge on readjust W of Salto Del Guaira (24°03'48"S, 54°19'12"W), UMMZ 206437, 1. Phylogenetic Biogeography of Creagrutus and Piabina The lack of resolution across much of the phylogeny for the Creagrutus-Piabina clade severely limits the historical biogeo- graphic information available for this group. The well-sup- ported clades, nonetheless, do demonstrate some informative patterns. The basal phylogenetic subdivision between Creagrutus and Piabina matches the noteworthy complete allopatry between the two genera (Figure 18), but with pronounced differences in the extent of areas of distribution of most species within the two clades. The known range for the single known species of Piabina {P. argentea; Figure 90) is much more extensive than that for most Creagrutus species (see distribution maps for var- ious species). Within Creagrutus a basal dichotomy exists be- tween two lowland Trans-Andean species (C nigrostigmatus of the Canos Pechilin and Zaragocilla, two small coastal rivers to the west of the mouth of the Rio Magdalena, and C. mara- caiboensis, a species endemic to Lago Maracaibo; Figure 17, Clade D) and the remaining species of the genus (Figure 17, Clade E), most of which occur in Cis-Andean South America. The distribution of the species in this basal dichotomy is con- gruent with a hypothesis of the existence of Creagrutus prior to the uplift of at least the northern portions of the Andean Cordil- leras. The Lago Maracaibo basin was mostly marine during the Late Tertiary up to approximately 10 million years before the present, but there was a progressive reduction of marine influ- ences in the next two million years (Lundberg et al., 1998), a period during which the major drainage systems on the conti- nent began to approximate their present forms. Thus, it seems likely that the division between the trans-Andean species pair (C nigrostigmatus and C. maracaiboensis) and the remainder of the genus dates back to at least eight million years before present. Evidence from the phylogeny indicates, however, that this is likely an underestimate. Although the lack of resolution in major portions of the phylogeny for Creagrutus precludes a definitive statement, it is noteworthy that the remainder of the Trans-Andean species occur at higher-nodes within the tree NUMBER 613 229 (Figure 17: Creagrutus affinis, Clade M; and various species in "remaining species"). Thus, the eight million year estimate for the minimum age for the Piabina-Creagrutus lineage actually applies to nodes higher in the phylogeny thereby extending the basal division between the clade consisting of C nigrostigma- tus and C. maracaiboensis and the remainder of the genus fur- ther back in time. The basal multitomy within Clade E (Figure 17) involves three western Amazonian upland species (C. muelleri, C. oura- nonastes, and C. peruanus), one of which, C ouranonastes, oc- curs at the highest known elevation for any member of the ge- nus. Regardless of the relationships between these three species, there appears to have been a speciation event between a western Amazonian component of Creagrutus and the re- mainder of the genus, with secondary sympatry at a later date given that both C. muelleri and C. peruanus occur sympatri- cally with congenerics within the Creagrutus species in Clade F (Figure 17). Four of the six clades within the assemblage delimited by Clade F (Figure 17) are based on characters with low retention indices and are poor bases for biogeographic hypotheses (see comments under "Intrageneric Relationships within Creagru- tus"). The two other clades within this multitomy are better supported and share an interesting pattern with distinct altitudi- nal difference between the sister groups within the clade. Crea- grutus kunturus, although occurring in many of the same rivers as its sister species, C. amoenus, inhabits higher portions of those western Amazonian systems. Although C. gephyrus is geographically separated from the known range of the species pair (C cracentis and C maxillaris), it also occurs at higher el- evations than do those two species. Comments on Creagrutus nigrostigmatus Creagrutus nigrostigmatus was described by Dahl (1960:353) on the basis of a series of specimens collected in Arroyo Pechilin, a small stream draining into the Caribbean Sea west of the mouth of the Rio Magdalena. Cala (1981; pers. comm., 1992) reported that the types of the species were lost and have not been located subsequently (Roman-Valencia and Cala, 1996:145). Harold and Vari (1994:10) consequently des- ignated a neotype for the species. Subsequent to that publica- tion a series of two specimens of C nigrostigmatus was discov- ered in the holdings of the California Academy of Sciences (CAS 149491; formerly SU 49491). Although not specifically noted as paratypes of C. nigrostigmatus, the evidently original label associated with the specimens contains the following in- formation: '''Creagrutus nigrostigmatus n. sp., Pechelin, July 14th 1955, Dahl." This information on the label matches the type locality for the species, and the date falls within the range of dates for the collection of the paratype series (1955-1957) cited by Dahl (1960:354). Dahl sent paratypes of various spe- cies that he described to GTS. Myers, then at Stanford Univer- sity (S.H. Weitzman, pers. comm., 1999), and these two speci- mens may, thus, represent the only portion of the type series known to be extant. RESUMO Creagrulus Giinther (1864) e Piabina Reinhardt (1867) sao diagnosticados como um grupo mono- filetico com base em uma serie de sinapomorfias de caracteres osteologicos e de anatomia de sistemas nao osseos. Subconjuntos destas sinapomorfias diagnosticam cada genero e resolvem parcialmente a filogenia intragenerica dentro de Creagrutus. Piabina, como previamente constituido, nao e monofiletico, sendo re- strito aqui para a especie-tipo P. argentea. Creagrudite Myers (1927) e Creagrutops Schultz (1944) com- partilham os caracteres diagnosticos de Creagrutus e sao considerados sinonimos juniores deste genero, a fim de tornar Creagrutus monofiletico. Piabarchus Myers (1928), proposto com base em uma especie de- scrita originalmente em Piabina, nao possui os caracteres derivados da linhagem Creagrutus-Piabina. Um total de 64 especies sao reconhecidas em Creagrutus, 56 das quais ocorrem a leste das Cordilheiras dos Andes. As especies cisandinas e suas distribuicoes sao: C. amoenus Fowler (1943a), Amazonas oeste; C. anary Fowler (1913), Rio Madeira; C. atratus, especie nova, bacia do Rio Meta; C. atrisignum Myers (1927), bacia do Rio Tocantins; C. barrigai, especie nova, leste do Equador e Peru; C. beni Eigenmann (1911), bacia do alto Rio Madeira; C. bolivari Schultz (1944), Rio Orinoco; C. britskii, especie nova, alto Rio Tocantins; C. calai, especie nova, Rio Meta; C. changae, especie nova, leste do Peru; C. cochui Gery (1964), Amazonas oeste; C. cracentis, especie nova, baixo Rio Tapajos; C. crenatus. especie nova, Rio Tocuyo, vertente do Caribe na Venezuela; C. ephippiatus, especie nova, Rio Siapa, bacia do alto Rio Ne- gro, Venezuela; C. figueiredoi, especie nova, alto Rio Tocantins e Rio Araguaia; C. flavescens, especie nova, leste do Equador; C. gephyrus Bohlke e Saul (1975), Amazonas oeste; C. gracilis, especie nova, nordeste do Peru e leste do Equador; C. gyrospilus, especie nova, oeste da bacia do Orinoco; C. holmi, es- pecie nova, nordeste do Peru; C. hysginus Harold et al. (1994), nordeste da Venezuela; C. ignotus, especie nova, alto Rio Tapajos; C. kunturus Vari et al. (1995), Oeste da Amazonia; C. lassoi, especie nova, vertente do Caribe na Venezuela; C. lepidus Vari et al. (1993), Rios Aroa e Urama, vertente do Caribe na Venezuela; C. machadoi, especie nova, Rio Caura, Venezuela; C. magoi, especie nova, bacia do Rio Orinoco; C. manu, especie nova, Rio Madre de Dios, Peru; C. maxillaris (Myers, 1927), alto Rio Orinoco, alto Rio Negro, e alto Rio Madeira; C. melanzonus Eigenmann (1909), Rio Cuyuni, leste da Venezuela ate Fleuve Sinnamary, French Guiana; C. melasma Vari et al. (1994), bacia do Rio Orinoco; C. menezesi, es- pecie nova, Rio Tocantins e tentativamente a bacia do Rio Negro; C. meridionalis, especie nova, Rio Par- aguay; C. molinus, especie nova, alto Rio Araguaia; C. mucipu, especie nova, Rio Tocantins; C. muelleri (Giinther, 1859), regiao amazonica do Equador; C. occidaneus, especie nova, Amazonas oeste; C. ortegai, especie nova, leste do Peru; C. ouranonastes, especie nova, terras altas no Peru; C. paraguayensis Mah- nert e Gery (1988), Rio Paraguay; C. pearsoni Mahnert e Gery (1988), bacia do alto Rio Madeira; C. peru- anus (Steindachner, 1875), bacia do Rio Ucayali; C. petilus, especie nova, tributarios a leste do Rio Ma- deira; C. phasma Myers (1927), alto Rio Negro e porcao sul do Rio Orinoco; C. pila, especie nova, Rio Aguaytia, leste do Peru; C. planquettei Gery e Renno (1989), Fleuve Approuague, French Guiana; C. provenzanoi, especie nova, Rio Cataniapo, Venezuela; C. runa, especie nova, alto Rio Negro; C. saxatilis, especie nova, bacia do Rio Tocantins; C. seductus, especie nova, alto Rio Araguaia; C. taphorni. especie nova, Rio Orinoco e vertente do Caribe do Rio Tuy; C. ungulus, especie nova, Rio Manu, sudeste do Peru; C. veruina, especie nova, Rio Cataniapo, Venezuela; C. vexillapinnus, especie nova, alto Rio Negro e Rio Orinoco; C. xiphos. especie nova, bacia do Rio Caura, Venezuela; e C. zephyrus, especie nova, alto Rio Negro no Brasil e Venezuela e alto Rio Orinoco. O numero de especies de Creagrutus reconhecidas aqui representa 337% do numero de especies consideradas validas anteriormente a Harold e Vari (1994). Ao contrario da pratica taxonomica recente, Piabina e reconhecido como um genero distinto, mas limi- tado a uma linica especie, P. argentea (Reinhardt, 1867), distribuida em varios rios do leste do Brasil. Chaves sao fornecidas para as especies de Creagrutus e Piabina nas maiores bacias hidrograficas da area de distribuicao destes generos. Creagrutus nasutus Giinther (1876) e considerado sinonimo de C. peruanus. Creagrutus boehlkei Gery (1972) e colocado na sinonimia de Creagrutus amoenus. Creagrutus pellegrini Puyo (1943) e assinalada para o genero Chalceus em Characidae. Lectotipos sao designados para Piabina argentea Reinhardt, Leporinus muelleri Giinther, Creagrutus nasutus Giinther, Creagrutus pearsoni Mahnert e Gery, Piabina peruana Steindachner, e Creagrutus phasma Myers. 230 Literature Cited Agostinho, A.A., H.F. Julio, Jr., L.C. 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Systematics, Osteology and Phylogenetic Relationships of Fishes of the Ostariophysan Subfamily Anostominae (Characoidei, Anosto- midae). Life Science Contributions, Royal Ontario Museum, 123:1-112. Index (Pages of principle discussions in italics) Acestrocephalus, 23 Acestrorhynchus, 19, 23 nasutus. 77 qffinis, Creagrutus, 2 Alestes lateralis, 21, 29 longipinnis, 21 amoenus. Creagrutus, 2,48, 58-62, 104,106, 107, 126, 167 analis. Piabarchus, 42, 224 Piabina. 42,224 anary, Creagrutus, 2,48, 63-65, 209 angulatus, Triportheus, 21, 29 Anodus, 23 Apareidon. 24 argentea, Creagrutus, 224 Piabina, 49, 224-228 Argonectes, 23 atratus, Creagrutus, 2,48, 66-/u. 42, 224 torrenticola, 42 Piabina, 4, 223-224 analis, 42,224 argentea, 49, 224-228 beni, 78, 178, 180 peruana, 181, 183 piquira, 3, 224, 226 Piabucus melanostomus, 29 Piaractus. 26 p/Va. Creagrutus, 3,48,92,189-191 piquira, Piabina, 3,224, 226 Pi tuna compacta, 103 planquettei, Creagrutus, 3,41,48,191-195 Poecilobrycon, 23 Potamorhina, 23 provenzanoi, Creagrutus, 3, 49, 100, 139, / P i - rn 213 Roeboides bouchellei, 27 dqyi, 27 dientonito, 27 //sea, 27 occidentalis, 27 /wia, Creagrutus, 3,49,198-200, 213 Saccodon, 24 Sartor 36 saxatilis, Creagrutus. 3,49, 102, 156,200-202 Schizodon. 23 seductus, Creagrutus, 3,49, 102, 202-205 Semaprochilodus squamilentis, 46 simus, Creagrutus. 3 spilurus. Xenocharax, 34 squamilentis, Semaprochilodus. 46 Stethaprion nasutus, 77 Synaptolaemus. 36 taphorni. Creagrutus. 3,49, 77, 116, 130, 205-209 Tetragonopterus, 29 torrenticola, Piabarchus, 42 Triportheus, 11,23, 25 angulatus. 21, 29 ungulus. Creagrutus, 3,49,209-213 veruina, Creagrutus. 3,41,49, 200, 213-215 vexillapinnus, Creagrutus, 3, 49, 215-218 Virilia pabrensis, 29 Xenocharax, 23 spilurus, 34 x/pfow, Creagrutus. 3, 41,49, 137,218-220. 222 xyrekes. 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