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SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY • NUMBER 240

On the Troglobitic Shrimps of the Yucatan Peninsula, Mexico (Decapoda: Atyidae and Palaemonidae)

H. H. Hobbs III
and Horton H. Hobbs, Jr.

SMITHSONIAN INSTITUTION PRESS

City of Washington

1976

A B S T R A C T

Hobbs, H. H., III, and Horton H. Hobbs, Jr. On the Troglobitic Shrimps of the Yucatan Peninsula, Mexico (Decapoda: Atyidae and Palaemonidae). Smithsonian Contributions to Zoology, number 240, 23 pages, 8 figures, 2 maps, 1976—Four troglobitic shrimps are reported to frequent the subterranean waters of the Yucatán Peninsula. Three are members of the family Atyidae: Typhlatya mitchelli, new species, and Typhlatya campecheae, new species, are described herein, and Typhlatya pearsei Creaser is redescribed. The fourth shrimp, Creaseria morleyi (Creaser), is a member of the family Palaemonidae. Illustrations as well as all known locality records are included for the four, and a key to all of the members of the genus Typhlatya is followed by a discussion of their interrelationships. A summary of the distribution of the four shrimps and maps indicating the localities where they were collected conclude the report.

OFFICIAL PUBLICATION DATE is handstamped in a limited number of initial copies and is recorded in the Institution’s annual report, Smithsonian Year. SERIES COVER DESIGN: The coral Montastrea cavernosa (Linnaeus).

Library of Congress Cataloging in Publication Data

Hobbs, H H

On the troglobitic shrimps of the Yucatan Peninsula, Mexico (Decapoda—Atyidae and Palaemonidae)

(Smithsonian contributions to zoology ; no. 240)

Supt. of Docs, no.: SI 1.27:240

Bibliography: p.

1. Typhlatya. 2. Creaseria morleyi. S. Crustacea—Mexico—Yucatan Peninsula. I. Hobbs, Horton Holcombe, 1914– joint author. II. Title. III. Series: Smithsonian Institution. Smithsonian contributions to zoology ; no. 240.

QLl.S54 no. 240 [QL444.M33] 591′.08s [595′.3843] 76–608123

On the Troglobitic Shrimps of the Yucatan Peninsula, Mexico (Decapoda: Atyidae and Palaemonidae)

H. H. Hobbs III
and Horton H. Hobbs, Jr.

____________

H. H. Hobbs III, Department of Biology, George Mason University, Fairfax, Virginia 22040. Horton H. Hobbs, Jr., Department of Invertebrate Zoology, National Museum of Natural History, Smithsonian Institution, Washington, D.C. 20560.

Introduction

As a result of extensive collections made in the Yucatán Peninsula by James R. Reddell, Texas Tech University, and associates, two atyid shrimps have been added to the known troglobitic fauna, and the distributions of the two previously reported shrimps (Atyidae and Palaemonidae) are much better known. Most of the specimens on which this report is based were obtained during two expeditions in the area during 1973.

Included here are descriptions of the two new species and a key to the members of the genus Typhlatya, together with a synonymy, redescription, summary of distribution, and illustrations of T. pearsei Creaser, 1936. The monotypic Creaseria morelyi (Creaser, 1936) is similarly treated although not redescribed, the description offered by Holthuis (1952) being entirely adequate.

Our knowledge of the troglobitic shrimp fauna of the Peninsula had its inception in Creaser’s reports (1936, 1938) of the crustaceans found by him and colleagues during the 1932 University of Michigan Yucatán Expedition. In the former publication, he described Palaemon morleyi from “San Isidro Cave” and Typhlatya pearsei from “Balam Canche Cave” and recorded both species from additional localities (see below). No further data on these animals appeared until 1950 when Cárdenas (p. 156) noted the occurrence of both species in “las cuevas de Hoctum [sic] y el Pachote,” and Holthuis erected the monotypic genus Creaseria to receive Creaser’s Palaemon morleyi. The latter shrimp was redescribed by Holthuis in 1952.

Typhlatya pearsei was reported from a presumably additional locality, “El Ponte Cave,” by Nicholas (1962:173). In personal communication, Mr. Reddell suggested that the cave name is probably an erroneous transcription of “Cueva del Pachote.” On the basis of a study of the eyes of C. morleyi and three Yucatán teleosts, Wilkens (1973c:58) concluded that the troglobitic adaptations of these animals probably began during “der letzten pleistozänen Kaltzeit begonnen.” Monod and Cals (1970), while describing Typhlatya galapagensis, conducted a morphological investigation of representatives of several atyid genera. Their conclusions were expressed in the recognition of four groups (séries) in the family. In addition, they proposed a terminology for setal classification, which insofar as seems appropriate, we have employed in the descriptions that follow.

The remaining references cited herein are to illustrations, keys, and notes on distribution.

We acknowledge with thanks the opportunity to examine the materials collected by James R. Reddell and colleagues. (See “Specimens Examined” under each of the species treated.) We are also grateful to Mr. Reddell for assisting us in spotting previously recorded localities. For their assistance in the preparation of the manuscript and/or their criticisms, we are indebted to Fenner A. Chace, Jr., Margaret A. Daniel, Carolyn B. Gast, and Isabel Pérez Farfante.

Family ATYIDAE

Genus Typhlatya

Typhlatya mitchelli, new species

FIGURES1, 2; MAP 1

DESCRIPTION.—Carapace lacking spines. Rostrum (Figure 1a,b) subspiniform, not extending anteriorly beyond eyes. Anterior margin of carapace produced in distinct rounded antennal lobe; pterygostomian lobe not well defined. Faint, premarginal transverse suture on posterodorsal region of carapace. Hepatic-branchiocardiac groove prominent (Figure 1a) and extending almost entire length of carapace.

Pleura of first five abdominal somites rounded, that of fifth broadly so and not at all suggestive of being angular (Figure 1a). Median portion of first abdominal sternite only slightly produced anteroventrally. Sixth abdominal somite (Figure 1a) approximately twice as long as fifth, and with rounded lobe at lateral base of telson; posteroventral margin of sternum produced in form of slender triangle.

Telson (Figure 1a,l,m) about 0.8 as long as sixth abdominal segment; 2 pairs of spiniform setae (“spines” of most authors) present dorsally, anterior pair situated at base of posterior third and posterior pair approximately midway between anterior pair and mid-posterior margin; posterior margin broadly rounded and bearing short pair of smooth lateral spiniform setae flanked mesially by longer (3.7 times longer than lateral pair) pair of spiniform setae bearing barbules proximomesially; between latter setae, 2 pairs of plumose setae present; 2 mesial pairs of setae somewhat equally spaced but of variable length, either pair being longer or shorter than longer lateral pair.

Eye (Figure 1a,b) subcorneal, proximomesial part covered by basal portion of rostrum but more than distal half clearly evident in dorsal aspect; facets and pigment lacking.

Antennule (Figure 1a,b,c) with peduncle reaching base of distal third or fourth of antennal scale, almost or quite approximating level of lateral spine of latter. Stylocerite acute, its apex almost reaching or slightly exceeding distal extremity of proximal podomere of peduncle. Distal segment of peduncle with dorsodistal plate bearing 18 to 20 setae. Antennular flagella subequal in length and at least 3 times as long as carapace, sometimes almost as much as 4 times as long; lateral ramus with proximal 15 to 17 articles broader than more distal ones, and ventral surface of fourth, fifth, or sixth through tenth to sixteenth articles with distal pair of lanceolate setae; additional single or paired setae occasionally present at midlength of eleventh through thirteenth articles.

Antennal scale (Figure 1a,b,d) approximately 2.5 times longer than greatest width, lateral margin provided with small spine at about base of distal fifth.

Mandible (Figure 1e) with 5 or 6 teeth on incisor area; prominent tuft of setae present at distal base of broad molar lobe.

Maxillae as illustrated (Figure 1f,g). First maxilliped (Figure 1h) with flagellum represented by elongate unsegmented process, here termed “flagellar lobule” (fl). Second maxilliped (Figure 1i) with well developed podobranch but lacking suture delimiting propodus and dactyl.

Third maxilliped (Figure 2a,b) surpassing antennal peduncle by entire length of ultimate podomere; exopod extending distally only slightly beyond base of penultimate podomore; ultimate podomore of endopod 1.2 to 1.4 times longer than penultimate. Flexor surface of ultimate podomore provided with 11 to 14 rows of plumose, distally spatulate setae (“soies cochléaires,” Monod and Cals, 1970:67, 86) (number in rows from proximal to distal end in one specimen: 2, 10, 12, 12, 10, 10, 9, 9, 7, 5, 2, 2, 2, 1); these setae followed by marginal row of 9 to 11 short, smooth spiniform setae (“spines” or “teeth” of most authors) flanked by submarginal row of 4 or 5 similar setae; more distal members of latter row smaller than those of marginal row; distal extremity spiniform but lacking articulated claw.

All pereiopods with exopods, that of fifth reduced, varying in length from barely exceeding distal extremity of basis to reaching distal end of basal fifth of merus. First pereiopod (Figure 2c) not reaching (if chela robust) or reaching (if chela slender) almost to distal end of antennal scale; carpus, including distal lobe, subequal to combined length of ischium and merus and 1.1 times as long as chela. Second pereiopod (Figure 2d,i,j) highly variable both in length and in relative degree of development of chela. In individuals with comparatively slender cheliped (Figure 2j), chela reaching slightly beyond distal extremity of antennal scale; in those with comparatively heavy cheliped (Figure 2i), chela reaching, at most, base of antennal scale; carpus in holotype divided with distal part slightly more than twice as long as proximal one, and combined podomeres twice as long as chela and about five-sixths combined length of ischium and merus; carpus in animals with slender chelae also about twice as long as chela, that in individuals with robust chelae often subequal in length to chela. Third pereiopod (Figure 2e) overreaching antennal scale by dactyl and three-fourths length of propodus; dactyl with 5 spiniform setae on flexor surface; propodus about 2.7 times longer than dactyl and about 1.5 times longer than carpus; ischiummerus slightly greater than 1.5 times as long as propodus, and bearing 5 submarginal spiniform setae. Fourth pereiopod (Figure 2f) overreaching antennal scale by half to total length of dactyl; dactyl with 3 spiniform setae on flexor margin; propodus about 2.7 times length of dactyl and about 1.5 times as long as carpus; ischiummerus subequal in length to carpus and propodus combined and bearing 4 somewhat evenly spaced submarginal spiniform setae; carpus with 1 such seta near distal end. Fifth pereiopod (Figure 2g,h) overreaching antennal scale by half length of dactyl; dactyl about 2.5 times as long as ischium, flexor margin bearing approximately 40 denticulate spiniform setae; propodus about twice as long as dactyl, 1.8 times as long as carpus, and bearing 2 submarginal spiniform setae near midlength, 1 subdistal and 2 distal ones; merus, bearing 1 submarginal spiniform seta distal to midlength, 1.3 times as long as propodus; ischium about 0.2 length of merus and lacking spiniform setae laterally.

FIGURE 1.—Typhlatya mitchelli, new species (holotypic female; all appendages from right side): a, lateral view; b, dorsal view of anterior region; r, antennule; d, amennal scale; e, mandible; f, first maxilla; g, second maxilla; h, first maxilliped; i, second maxilliped; j, first pleopod: k, second pleopod; l, telson and uropods; m, posterior region of telson. (fl = flagellar lobule; scales in mm.)

Endopod of first pleopod of female (Figure 1j) small, length 0.3 that of exopod and slightly less than 0.5 that of protopodite. Second pleopod of female (Figure 1k) with exopod only slightly longer than endopod and about 1.5 times as long as protopodite.

Lateral ramus of uropod with prominent movable lateral spiniform setae situated immediately mesial to very small fixed spiniform projection.

Branchial series composed of 5 pleurobranchs on pereiopodial somites, arthrobranch at base of third maxilliped, and podobranch on second maxilliped; epipods present on third maxilliped and all but fifth pereiopods, and coxal setae borne on all pereiopods.

SIZE.—Carapace length of females, 3.4 to 4.8 mm (holotype, 4.8 mm); juveniles 1.4 to 2.9 mm. Males and ovigerous females unknown.

COLOR.—Preserved specimens translucent to white.

TYPE-LOCALITY.—Cenote Kabahchen, Maní, Yucatán, Mexico. 1 August 1973, R. W. Mitchell, collector.

DISPOSITION OF TYPES.—The holotypic female (USNM 151904) and 10 paratypic females are deposited in the National Museum of Natural History, Smithsonian Institution under the catalog designation USNM (= former United States National Museum). Of the remaining paratypes, 12 females are in The Museum, Texas Tech University, Lubbock, Texas; and 2 females are in the Instituto de Biología, Universidad Nacional Autónoma de Mexico.

SPECIMENS EXAMINED.—Twenty-five females, constituting the type series, were obtained in the State of Yucatán, Mexico, as follows (those specimens marked by an asterisk are in the Smithsonian Institution, those bearing two asterisks in the Instituto de Biología, and all others in The Museum, Texas Tech University; locality numbers in parentheses correspond to the locality numbers in appendix table and on Map 1). (1) Cenote de la Culebra, 1art, 1 juvenile, 27 Mar 1973, James R. Reddell, coll. (2) Grutas de Tzab-Nah, 2 km S Tecoh, 3art, 6 Aug 1973, Deborah Denson, R. W. Mitchell, S. A. Mitchell, and S. R. Mitchell, coll. (3) Cenote Ch’en Mul, Ruinas de Mayapán, 2art, 26 Apr 1973, J. R. R., David McKenzie, Martha H. McKenzie, and Mary Butterwick, coll. (4) Type-locality, 5art* + holotype. 1 Aug 1973, R. W. M., coll. (5) Cenote de Sodzil, 5 km W Sucopo, 5art*, 31 Mar 1973, J. R. R., coll. (6) Cenote (=Cueva) de Orizaba, 8 km S Buenaventura, 1art, 1 Apr 1973, J. R. R., coll. (7) Cenote Aká Chen, 1 km NE Tixcancal, 3art, 2 Apr 1973, J. R. R., D. M., M. H. M., M. B., and S. M., coll. (8) Cenote de la Paca, 7 km E Tikuch, 2art, 11 Apr 1973, Stuart Murphy, coll. (9) Cenote de Xtacabihá, 1 km SW Xalau, 2art**, 11 Apr 1973, J. R. R., M. H. M., and S. M., coll. (See Map 1 and appendix table for distribution and shrimp associates.)

FIGURE 2.—Typhlatya mitchelli, new species (a–h, holotypic female; all appendages from right side): a, third maxilliped; b, distal portion of same; c–g, first through fifth pereiopods, respectively; h, distal end of dactyl of fifth pereiopod; i, second pereiopod of female from Cenote Ch’en Mul, Yucatán; j, same of female from Grutas de Tzab-Nah, Yucatán. (Scales in mm.)

REMARKS.—Unfortunately, few specimens are available from any of the nine localities from which this species is known; the largest series consists of six individuals from Cenote Kabahchen, the type-locality. Moreover, no male was obtained in any of the caves.

Among the most conspicuous variations noted in Typhlatya mitchelli is the relative length of the exopod of the fifth pereiopod. In some specimens it scarcely reaches the ischiomeral articulation, while in most it ranges from the base to the distal end of the basal fifth of the merus.

Slight differences occur in the disposition of setae along the flexor margin of the distal podomere of the third maxilliped. The proximal series of plumose distally spatulate setae consists of 11, rarely 12, rows, followed distally by a single row of 9 to 11, occasionally 12 smooth spiniform setae.

Worthy of note are variations that exist in the proportions of the 3 distal podomeres of the second pereiopod. In those individuals in which the carpus is subequal in length to the chela, the latter is robust, appearing swollen. Furthermore, the merus and exopod are correspondingly short (Figure 2i). In those chelipeds in which the length of the chela is only approximately one-half that of the carpus, the chela is slender; also the merus and exopod are elongate (Figure 2j). The structure of the carpus of the second pereiopod of the holotype (Figure 2d) is unusual; it is divided, the two articles together proportionately almost as long as that in Figure 2j.

None of the variations mentioned have been correlated with specific localities or limited portions of the range.

ETYMOLOGY.—This shrimp is named in honor of our friend, Robert W. Mitchell, who collected part of the type series and who has contributed much to our knowledge of the troglobitic fauna of Mexico.

Typhlatya campecheae, new species

FIGURES 3, 4; MAP 1

DESCRIPTION.—Carapace lacking spines. Rostrum (Figure 3a,c) triangular, extending anteriorly beyond eyes, and sometimes almost reaching distal end of proximal podomere of antennular peduncle. Anterior margin of carapace produced in broadly rounded antennal lobe and much less prominent pterygostomian lobe (Figure 3a). Posterodorsal surface of carapace marked by faint premarginal transverse suture, lateral surface bearing conspicuous hepatic-branchiocardiac groove extending almost entire length of carapace.

Pleura of first 3 abdominal somites rounded, those of fourth subacute posteroventrally, and those of fifth virtually acute (Figure 3a,b). Median portion of first abdominal sternite only slightly produced anteroventrally. Sixth abdominal somite approximately twice as long as fifth and with lobe at lateral base of telson rounded; posteroventral margin of sternum produced in short projection in form of isosceles triangle.

Telson (Figure 3a,b,n,o) subequal in length to sixth somite, provided with 2 pairs of spiniform setae dorsally, anterior pair situated slightly anterior to base of posterior third, and posterior pair midway between anterior pair and posterolateral extremity; posterior margin rounded and bearing 2 pairs of smooth spiniform setae laterally (lateral pair only about one-fourth as long as mesial pair) and 4, occasionally 5, equally spaced, plumose, spiniform setae between long smooth setae; plumose setae highly variable in length, extending posteriorly as far as, exceeding, or not reaching level of distal extremity of longest pair of smooth setae.

Eye (Figure 3a,c) globular, proximomesial portion covered by rostrum but more distolateral portion clearly visible in dorsal aspect; facets and pigment lacking.

Antennule (Figure 3a,c,d) with peduncle reaching beyond lateral spine on antennal scale, often to distal margin of latter. Stylocerite acute, falling short of, or slightly, if at all, exceeding distolateral margin of proximal segment of peduncle. Distal podomere of peduncle with dorsodistal plate bearing about 10 setae. Antennular flagella subequal in length and slightly more than 3 times as long as carapace; lateral ramus with 11 to 13 proximal articles broader than more distal ones; ventral surface of second, third, or fourth through tenth articles each with row of 2 to 5 lanceolate setae borne on distal margin and also often at midlength on all but proximal 2 or 3.

FIGURE 3.—Typhlatya campecheae, new species (appendages from right side of holotypic male): a, lateral view of holotype; b, lateral view of abdomen of ovigerous female; c, dorsal view of anterior region of holotype; d, antennule; e, antennal scale; f, mandible; g, first maxilla; h, second maxilla; i, first maxilliped; j, second maxilliped; k, first pleopod; l, second pleopod; m, appendices interna and masculina; n, telson and uropods; o, posterior region of telson. (fl = flagellar lobule; scales in mm.)

Antennal scale (Figure 3a,c,e) approximately 2.3 times as long as broad, lateral border provided with small spine at base of distal fourth.

Mandible (Figure 3f) with 4 or 5 teeth on incisor lobe; molar lobe broadly separated from incisor lobe, area between bearing prominent tuft of setae adjacent to former, and 2 bent setae situated between tuft and proximalmost tooth.

Maxillae as illustrated (Figure 3g,h). First maxilliped (Figure 3i) with flagellar lobule (fl) strongly produced distomesially. Second maxilliped (Figure 3j) with well developed podobranch, and with clearly defined suture delimiting propodus and dactyl.

Third maxilliped (Figure 4a,b) overreaching antennal scale by one-fourth to one-half length of ultimate podomere; exopod extending distally between midlength and distal extremity of penultimate podomere; ultimate podomere 1.3 to 1.6 times as long as penultimate. Flexor surface of ultimate podomere provided with 10 or 11 transverse rows of plumose, distally spatulate setae along proximal two-thirds, followed distally by marginal row of 4 to 6 short, smooth, spiniform setae; distal extremity spiniform but lacking articulated claw.

All pereiopods provided with exopods; that of fifth highly variable in degree of development, ranging from exceedingly small and scarcely surpassing midlength of ischium to moderately robust and almost reaching distal end of merus. First pereiopod (Figure 4c) attaining proximal fourth of antennal scale; carpus, including distal lobe, subequal in length to combined length of ischium and merus, and slightly longer than chela. Second pereiopod (Figure 4d) reaching midlength of antennal scale; carpus 1.2 times as long as either chela or merus. Third pereiopod (Figure 4e) overreaching antennal scale by length of dactyl and one-fourth of propodus; dactyl with 8 spiniform setae on flexor margin; propodus 4 times as long as dactyl and about 1.8 times length of carpus; merus 0.8 to subequal in length to propodus and bearing 3 spiniform setae laterally; ischium subequal in length to dactyl and armed with 1 spiniform seta. Fourth pereiopod (Figure 4f) overreaching antennal scale by no more, usually less, than length of dactyl, latter bearing 8 spiniform setae on flexor margin; propodus about twice length of dactyl and about 1.8 times length of carpus; merus almost twice as long as carpus, about 1.2 times length of propodus, and bearing 2 submarginal spiniform setae on distolateral half; carpus without lateral spine; ischium distinctly longer than dactyl with 1 lateral spiniform seta slightly distal to midlength. Fifth pereiopod (Figure 4g,h) extending anteriorly to about same level as fourth; dactyl subequal in length to ischium, flexor margin bearing 45 to 50 denticulate spiniform setae; propodus slightly less than twice length of dactyl and about twice as long as carpus; merus about 0.8 length of propodus and bearing 2 spiniform setae laterally, one slightly distal to midlength, and other near base of distal fifth of podomere; ischium slightly more than half length of merus and lacking spiniform setae laterally.

Endopod of first pleopod of male (Figure 3k) with conspicuous marginal setae, about one-third as long as exopod, and about half length of protopodite. Second pleopod of male (Figure 3l,m) with appendix masculina much longer than appendix interna and bearing about 12 apical and subapical spines.

Length of endopod of first pleopod of female about two-thirds that of exopod and approximately two-thirds that of protopodite. Length of endopod of second pleopod of female (Figure 3b) about three-fourths that of exopod and subequal to that of protopodite.

Lateral ramus of uropod with small, although prominent, movable spiniform seta laterally at about base of distal fifth.

Branchial series composed of 5 pleurobranchs on pereiopodial somites, arthrobranch at base of third maxilliped, and podobranch on second maxilliped; epipods on third maxilliped and on all pereiopods except fifth; and coxal setae on all pereiopods.

SIZE.—Carapace length of males, 3.0 to 3.9 mm (holotype 3.8 mm); of females, 3.1 to 4.5 mm. Two ovigerous females (carrying 9 and 11 eggs, 2 additional unattached eggs in container), each with carapace length of 3.9 mm; eggs approximately 0.8 by 1.1 mm. Carapace length of juveniles ranging from 1.4 to 2.7 mm.

COLOR.—Preserved specimens translucent to white; cephalothorax with yellowish orange mass (preservation too poor to determine whether ovary or hepatopancreas) internally.

TYPE-LOCALITY.—Grutas de Xtacumbilxunam, Bolonchenticul, Campeche, Mexico. The shrimp were described by James R. Reddell as occurring “in vast numbers in small pool containing amphipods and ostracods.”

FIGURE 4.—Typhlatya campecheae, new species (appendages from right side of holotypic male): a, third maxilliped; b, distal portion of same; c–g, first through fifth pereiopods, respectively; h, distal end of dactyl of fifth pereiopod. (Scales in mm.)

DISPOSITION OF TYPES.—The holotypic male (USNM 151903), 6 paratypic males, and 10 paratypic females are deposited in the National Museum of Natural History, Smithsonian Institution. Twenty-nine male, 100 female, and 21 juvenile paratypes are in The Museum, Texas Tech University, Lubbock, Texas; and 5 paratypes of each sex are in the Instituto de Biología, Universidad Nacional Autónoma de Mexico.

SPECIMENS EXAMINED.—Known only from the type-locality: 1art, 4art, 2 ovigerous art, 19 Apr 1973. and 40art. 109 art, and 21 juveniles, 13 May 1973, J. R. R., D. M., M. H. M., S. M., and M. B., coll.

REMARKS.—Typhlatya campecheae is known only from the type-locality, thus variations cited below represent differences occurring in the single population. This is the only population of shrimp examined during the present study that is represented by adequate numbers to reflect its composition. The sample of 13 May 1973 consists of 40 males, 109 females, and 21 juveniles.

The exopod of the fifth pereiopod ranges in length from barely reaching the midlength of the ischium to almost attaining the middle third of the merus. In contrasting “short” and “long” exopods, those in 28 males and 90 females reached no farther than the base of the distal fourth of the ischium, whereas in 12 males and 19 females, they extend beyond that level—79.2% of the population sample have “short” exopods and 20.8% have “long” ones.

Unlike that of T. mitchelli, the setal complement along the flexor margin of the distal podomere of the third maxilliped of all of the specimens examined consists of 11 rows of plumose, distally spatulate setae, followed by a row of 5 or 6 smooth spiniform ones.

The rostrum reaches anteriorly to between midlength and the distal extremity of the proximal podomere of the antennular peduncle.

The same variations pointed out in the second pereiopod of T. mitchelli (which see) obtain in T. campecheae and T. pearsei. No differences were noted in the forms of this appendage in males and females of the latter two species.

ETYMOLOGY.—This shrimp (found in Campeche) is unique in being the only Mexican member of the genus known from beyond the limits of the state of Yucatán.

Typhlatya pearsei Creaser

FIGURES 5, 6; MAP 1

Typhlatya pearsei Creaser, 1936:128–130, 131, figs. 31–41 [type-locality, “Balam Canche Cave, 4.8 km E, 0.8 km S Chichen Itza.” Yucatán. Mexico]; 1938:162–164.—Pearse, 1936:24; 1945:169, 170, figs. 31–41.—Chace, 1942:100; 1943:30, 32: 1954:319, 323; 1972:15.—Cárdenas, 1950:156.—Villalobos, 1951:215.—Rioja, 1953:286, 292; 1971:524.—Holthuis, 1955:26; 1956:52; 1974:141.—Balss, 1955:1310.—Nicholas. 1962:173.—Chace and Hobbs, 1969:20–21.—Straskraba, 1969:25.—Botosaneanu and Holthuis, 1970:122, 123, 127.—Monod and Cals, 1970:69, 73, 78, 82, 84, 85, 93, 94.—Reddell, 1971:25.—Chace and Manning, 1972:17—Croizat et al., 1974:275. fig. 2.—Silva Taboada, 1974:45.—Monod, 1975:99, fig. 1.

Typhlatya.—Creaser, 1938:159.—Pearse, 1938:13, 15; 1945:167.—Argano, 1972:33.—Croizat et al., 1974:276 [in part].

Typhlata Cárdenas, 1950:157 [erroneous spelling].

Typhlatya pearsi Rioja, 1953:293.—Vandel, 1964:178; 1965:139.—Peck, 1974:21 [erroneous spelling].

Typhlatya pearsii Cendrero, 1971:1150 [erroneous spelling].

DESCRIPTION.—Carapace lacking spines. Rostrum (Figure 5a,b) acuminate, reaching midlength to slightly beyond penultimate podomere of antennular peduncle. Anterior margin of carapace produced in prominent broad to narrow and tapering antennal lobe (lobe never acute), followed ventrally by long shallow excavation obliterating dorsal limit of pterygostomian lobe (Figure 5a). Posterodorsal surface of carapace lacking shallow premarginal transverse suture, lateral surface bearing conspicuous, sinuous, hepatic-branchiocardiac groove extending almost entire length of carapace.

Pleura of first 3 abdominal somites rounded, those of fourth subacute, and those of fifth acute to narrowly rounded (Figure 5a). First abdominal sternite somewhat broadly produced anteroventrally. Sixth abdominal somite little less than twice as long as fifth and with rounded lobe at lateral base of telson; posteroventral margin of sternum produced in short equilateral triangle forming preanal plate.

Telson (Figure 5a,o,p) subequal in length to sixth abdominal somite and provided with 2 pairs of spiniform setae dorsally; anterior pair situated slightly anterior to base of posterior third, and posterior pair midway between anterior pair and posterolateral extremity of telson (asymmetry and double anterosinistral spines in Figure 5o,p atypical); posterior margin rounded and bearing 2 pairs of smooth lateral spiniform setae (lateralmost pair only about one-fourth as long as more mesial pair) and 2 pairs of subequally spaced plumose setae, their length variable but mesialmost pair frequently longest of 4 pairs.

Eyes (Figure 5a,b) globular, sometimes with slight tuberculiform prominence anterolaterally; posteromesial portion covered by rostrum but much of eye clearly evident in dorsal aspect; facets and pigment lacking.

FIGURE 5.—Typhlatya pearsei (all appendages from right side; a, male from Cenote ( = Cueva) de Hoctún, Yucatán; b–l,o,p, male from Cenote de las Abejas, Yucatán; m,n, female from latter): a, lateral view; b, dorsal view of anterior region; c, antennule; d, antennal scale; e, mandible; f, first maxilla; g, second maxilla; h, first maxilliped; i, second maxilliped; j, first pleopod; k, second pleopod; l, appendices interna and masculina; m, first pleopod; n, second pleopod; o, telson and uropods; p, posterior region of telson. (fl = flagellar lobule; scales in mm.)

Antennule (Figure 5a,b,c) with peduncle rarely surpassing level of lateral spine of antennal scale. Stylocerite acute, and usually slightly overreaching distal extremity of proximal podomere. Distal podomere of peduncle with dorsodistal plate bearing about 16 plumose setae. Antennular flagella subequal in length and approximately twice length of carapace; lateral ramus with 12 or 13 proximal articles broader than more distal ones, and ventral surface of third through sixteenth articles bearing transverse rows of 2 to 4 lanceolate setae, all except third and sixteenth with 2 rows at midlength and along distal margin.

Antennal scale (Figure 5a,b,d) about twice as long as broad, lateral border provided with spine at approximately two-thirds length from base.

Mandible (Figure 5e) with incisor lobe bearing 7 or 8 teeth and 2 small setae at opposable base of lobe; prominent tuft of plumose setae present between 2 setae and molar lobe.

Maxillae as illustrated (Figure 5f,g). First maxilliped (Figure 5h) with flagellar lobule (fl) strongly produced distomesially. Second maxilliped (Figure 5i) with well developed podobranch and with suture delimiting propodus and dactyl.

Third maxilliped (Figure 6a,b) overreaching antennal scale by as much as half length of ultimate podomere; exopod extending distally slightly beyond proximal third of antepenultimate podomere; ultimate podomere about 1.2 times as long as penultimate. Flexor surface of ultimate podomere provided with 10 or 11 transverse rows of plumose, distally-spatulate setae along proximal two-thirds, followed distally by marginal row of 4 to 6, short smooth spiniform setae; distal extremity acute but usually lacking claw.

All pereiopods provided with exopods; that of fifth very much reduced, barely surpassing distal end of basis. First pereiopod (Figure 6c) reaching end of proximal third of antennal scale; carpus, including distal lobe, about 0.8 as long as ischiomeral podomere and subequal in length to chela. Second pereiopod (Figure 6d) reaching base of distal third of antennal scale; carpus almost 1.5 times as long as either chela or merus. Third pereiopod (Figure 6e) overreaching antennal scale by at least length of dactyl and sometimes by as much as additional one-fourth of propodus; dactyl with 9 spiniform setae on flexor surface; propodus almost 2.5 times as long as dactyl; carpus about half as long as propodus and with single spiniform seta laterodistally; merus approximately 1.2 times length of propodus and bearing 4 spines laterally; ischium about half as long as dactyl and lacking spiniform setae. Fourth pereiopod (Figure 6f) overreaching antennal scale by half to total length of dactyl; dactyl shorter or subequal in length to ischium, its flexor margin armed with 8 spiniform setae; remaining podomeres with setae as on third. Fifth pereiopod (Figure 6g,h) reaching distal end of antennal scale; dactyl about twice as long as ischium, its flexor margin bearing 40 or more denticulate spiniform setae; propodus slightly less than twice length of dactyl, almost twice as long as carpus, and bearing row of 3 marginal slender spiniform setae; merus little less than 1.5 times length of propodus and bearing as many as 3 lateral spiniform setae; ischium about one-sixth as long as merus and lacking spiniform setae.

Endopod of first pleopod of male (Figure 5j) with conspicuous marginal setae and slightly more than one-third as long as exopod and little more than two-thirds length of protopodite. Second pleopod of male (Figure 5k,l) with appendix masculina much longer than appendix interna and bearing about 16 apical and subapical spines.

Length of endopod of first pleopod of female (Figure 5m) about one-fourth that of exopod and little less than one-half length of protopodite. Second pleopod of female (Figure 5n) with endopod 0.8 as long as exopod and about two-thirds as long as protopodite.

Lateral ramus of uropod with small movable spiniform seta situated in lateral angular excision at base of distal fifth.

Branchial series composed of 5 pleurobranchs on pereiopodial somites, arthrobranch at base of third maxilliped, and podobranch on second maxilliped; epipods on third maxilliped and on all (except fifth) pereiopods; and coxal setae on all pereiopods.

SIZE.—Carapace length of males, 3.6 to 3.8 mm; of females, 3.3 to 5.2 mm. Carapace length of juveniles ranging from 1.3 to 2.3 mm. Creaser’s holotypic female (USNM 98364) has a carapace length of 3.9 mm. The measurement cited by him of a cephalothoracic length of 5.0 mm included the rostrum. We obtained a corresponding measurement of 4.7 mm.

FIGURE 6.—Typhlatya pearsei (appendages from right side of male from Cenote de las Abejas, Yucatán): a, third maxilliped; b, distal portion of same; c–g, first through fifth pereiopods, respectively; h, distal end of dactyl of fifth pereiopod. (Scales in mm.)

COLOR.—Preserved specimens translucent to white.

SPECIMENS EXAMINED.—In addition to the type series from Cueva Balaam Canché, we have examined the following, all from previously reported localities in Yucatán (those specimens marked by an asterisk are in the Smithsonian Institution; all others are in The Museum, Texas Tech University; locality numbers in parentheses correspond to locality numbers in appendix table and on Map 1). (2) Grutas de Tzab-Nah, 2 km S Tecoh, 4art, 4 juveniles, 22 Apr 1973, J. R. R. and D. M., coll. (4) Cenote Kabahchen, Maní, 5art, 1 Aug 1973, J. R. R., D. M., and S. M., coll. (9) Cenote de Xtacabihá, 1 km SW Xalau, 8art, 11 Apr 1973, J. R. R., M. H. M., and S. M., coll. (12) Cenote Calchum, 3 km E San Barnardo, 1art, 16 Apr 1973, J. R. R., D. M., and S. M., coll. (13) Cenote de las Abejas, 1art, 2art*, 16 Apr 1973, D. M. and S. M., coll. (14) Cueva de San Isidro, Mérida, 1art, 21 Mar 1973, J. R. R. and S. M., coll. (15) Cueva de Santa Elena (=Cueva de los Camarones), 5 km S Telchac Puerto, 3art, 24art, 6 juveniles, 22 Mar 1973, J. R. R. coll. (17) Cenote (=Cueva) de Hoctún, 7art*, 16 Mar 1973, J. R. R., S. M., D. M., M. H. M., and M. B., coll. (20) Gruta de Chac, S of Kabah, 1art*, 24 Nov 1962, E. W. Andrews, coll.

We have not seen specimens from (11) Cueva del Pochote (Cárdenas, 1950:156), or (19) Cueva del Ponte (Nicholas, 1962:173). The record, “Caverna Chichén Itzá,” cited by Pearse (1945:169), is almost certainly an error of transcription from Creaser’s (1938:162) list of localities in which he included “Balaam Canche Cave” (= (18) Cueva Balaam Canché). 4.8 km E, 0.8 km S of Chichén Itzá, Yucatán . (See Map 1 and appendix table for distribution and shrimp associates.)

REMARKS.—In all of the specimens from the type-locality, Gruta de Chac, Cenote de Hoctún, and Cenote de las Abejas, the rostrum reaches the distal extremity of the penultimate podomere of the antennular peduncle. In those specimens from the other localities cited above, it does not extend quite so far anteriorly, terminating between midlength and base of distal four-fifths of penultimate podomere.

In comparison with the two species previously discussed, there is remarkable uniformity in the development of the exopod of the fifth pereiopod. In all of the specimens examined it is exceedingly small, extending at most, half to two-thirds its length beyond the distal end of basis (Figure 1g).

The distribution of setae on the flexor margin of the distal podomere of the third maxilliped is relatively uniform. The proximal rows of plumose, distally spatulate setae number 10 or 11 and these are followed distally by a single series of 5 or 6 smooth spiniform ones.

The rostrum extends anteriorly to between midlength and the distal end of the penultimate article of the antennular peduncle.

The conspicuous dimorphism noted in the second pereiopods of the females of T. mitchelli (see “Remarks” under species description) and in both sexes of T. campecheae also occurs in both males and females of T. pearsei.

Notes on Relationships

The reader is referred to Monod and Cals (1970) in which both inter- and intrageneric relationships are discussed in some detail. The following observations, however, seem appropriate in view of the discovery of four additional species of the genus that were unknown to these authors. Pertinent also are the “Remarks” by Chace and Manning (1972:16–17), as well as the zoogeographic discussions by Croizat, Nelson, and Rosen (1974) and Monod (1975).

Except for Typhlatya rogersi, which was reported by Chace and Manning (1972) to occur in saltwater pools with subterranean marine passages on Ascension Island, and T. galapagensis, which occurs in brackish or slightly brackish water on Isla de Santa Cruz, all of the other species of the genus frequent freshwater habitats.

In considering the affinities of the eight species assigned to the genus, various groupings are possible depending upon which characters are considered. For example, the structure of the first maxilliped is remarkably uniform among all of them except T. galapagensis and T. rogersi. That in each, however, is unique in that the caridean lobe of the former is unusually large and lacks a distinct flagellar lobule, whereas in T. rogersi the caridean lobe is not enlarged and the flagellar lobule is vestigial.

A comparison of the relative length of the rostrum provides another grouping: T. rogersi resembles T. pearsei, T. consobrina, and T. campecheae in that the apex overreaches the eyes; in contrast, in the other four species, the rostrum does not attain the distal extremity of the eyes.

On the basis of the presence or absence of pigment in the eye, only T. garciai and T. monae possess a pigment spot; in the other species, the eyes are as colorless as the integument.

The shortest, stockiest pereiopods, particularly the first and second pairs, occur in T. rogersi, and it is of interest that in T. mitchelli, T. campecheae, and T. pearsei there exists an apparent dimorphism in which some members possess short, more stocky first and second pereiopods than do others; in the latter two species, this dimorphic condition occurs in members of both sexes.

Key to the Species

The flexor margin of the dactyl of the fifth pereiopod of T. consobrina and T. galapagensis, and at least sometimes in T. mitchelli and T. rogersi, bears no more than four denticles, whereas that of the other four species supports five or more.

A consideration of the relative development of the exopod of the fifth pereiopod regiments yet another grouping, for only in T. monae and T. pearsei is it greatly reduced; in all of the other species it is comparatively well developed.

In the proportions of the telson, only in T. garciai is it as much as three times longer than broad, and only in T. galapagensis, and occasionally in T. campecheae and T. pearsei, is it less than twice as long as broad.

Data on the distribution of setae on the flexor surface of the distal podomere of the third maxilliped are limited to six species. Expressed by “number of rows of plumose, distally spatulate setae” / “number of spiniform setae in distal row,” the following have been noted: T. campecheae 10–11/4–6; T. galapagensis 6/5; T. mitchelli 11–14/9–11; T. monae 10/5; T. pearsei 10–11/4–6; and T. rogersi 12/5. Again, T. galapagensis and T. mitchelli stand out as being different from one another and each distinct from the others.

Unfortunately, males of T. monae, T. mitchelli, and T. galapagensis are unknown, and information relative to the appendix masculina is available for only T. campecheae, T. consobrina, T. pearsei, and T. rogersi. The appendix masculina of T. consobrina is much shorter than the appendix interna and is devoid of setae (Botosaneanu and Holthuis, 1970). In T. rogersi, it is likewise shorter than the appendix interna, but it is armed with about 7 setae. In T. campecheae and T. pearsei, the appendix masculina is distinctly longer than the appendix interna and bears 12 to 14 setae.

Seemingly, the most divergent species are the saltwater inhabitants of Ascension Island (T. rogersi) and Isla de Santa Cruz (T. galapagensis). Rather closely allied to one another are T. garciai and T. monae, and these insular forms are linked, through the Cuban T. consobrina, to T. campecheae and T. pearsei, which inhabit the Yucatán Peninsula. At least in some respects, T. mitchelli stands intermediate, both in morphology and in geographic position, between the Caribbean species with a short rostrum, T. garciai and T. monae, and the seemingly disjunct T. galapagensis from Isla de Santa Cruz in the Galapagos Islands.

Family PALAEMONIDAE

Genus Creaseria

Creaseria morleyi (Creaser)

FIGURES 7, 8; MAP 2

Palaemon morleyi Creaser. 1936:126–128, 131, figs. 25–30 [type-locality, San Isidro Cave, Salar Colony, Mérida, Yucatán, Mexico]; 1938:163–164.—Pearse, 1936:24; 1945:169, figs. 25–30.—Chace, 1943:31, 33.—Anonymous, 1947:128.—Cárdenas. 1950:156—Villalobos, 1951:215—Rioja, 1953:293, 294.—Holthuis. 1955:44.

Palaemon.—Pearse, 1938:13, 15; 1945:167.—Cárdenas, 1950:157.

Palaemon Morleyi.—Carreño, 1950:24.

Creaseria morleyi.—Holthuis, 1950:6 [by implication]; 1952:153–154, 356, pl. 40; 1955:44 [by implication], fig. 22a; 1956:56–57: 1974:141.—Chace, 1954:323.—Maccagno and Cucchiari, 1957:207 [by implication].—Nicholas, 1962:174.—Rioja. 1962:38. 40; 1971:522.—Vandel, 1964:179: 1965:140.—Rodríguez de la Cruz, 1965:76, 97–98, pl. 4:fig. A.—Andrews, 1970:4.—Reddell, 1971:25.—Parzefall and Wilkens, 1972:66.—Wilkens, 1973a:327, 328, 330, fig. 3; 1973b:205; 1973c:50–54. 56, 58, 59, figs. 1–3.

Creaseria.—Holthuis, 1952:2, 152–153; 1956:69.—Chace, 1972:17.—Argano, 1972:33.

Palaemon morley.—Rioja, 1953:286 [lapsus calami].

PREVIOUSLY KNOWN LOCALITIES.—Insofar as known, this shrimp is confined to the state of Yucatán, Mexico. Creaser (1936:128) reported it from the following (numbers in parentheses correspond to locality numbers in appendix table and on Map 2): (14) Cueva de San Isidro, Mérida; (18) Cueva Balaam Canché, 4.8 km E, 0.8 km S Chichén Itzá; (22) Cenote (=Cueva) Amil on Hacienda Tixcacae, 14 km SE, 2 km E of Mérida: and questionably from (28) Cenote de Sambulhá (=Cueva San Bulha), Motul. The same author (1938:163) added the following: (17) Cenote (=Cueva) de Hoctún; (21) Cueva Xpukil (=Cuvea Spukil) at Calcehtok; (23) Cueva Yunchén at Libre Unión; (24) Cueva Chac Mol, near Tohil; (25) Cueva Góngora at Oxkutzcab; and (27) a questionable sight record at Cueva Xconsacab, Tizamin. The last recorded locality is that of Cárdenas (1950:156), (11) Cueva del Pochote, Muna.

ADDITIONAL LOCALITIES AND SPECIMENS EXAMINED.—Several lots of specimens examined in the present study were collected in two of the localities, (14) and (17), just cited. (Those specimens marked by an asterisk are in the National Museum of Natural History, Smithsonian Institution; all others are in The Museum, Texas Tech University.) (1) Cenote de la Culebra, 2art, 3 Aug 1973, R. W. M. and F. E. A., coll. (2) Grutas de Tzab-Nah, 2 km S Tecoh, 1art*, 2art*, 22 Apr 1973, J. R. R. and D. M., coll. (4) Cenote Kabahchen, Maní, 1art, 1art, 1 Aug 1973, R. W. M., coll. (5) Cueva de Sodzil, 5 km W Sucopo, 3art, 31 Mar 1973, J. R. R., D. M., M. M., and S. M., coll. (8) Cenote de la Paca, 7 km E Tikuch, 1art, 1art, 11 Apr 1973, S. M., coll. (11) Cueva del Pochote, 1art*, 2art*, 27 Mar 1947, M. Cárdenas and B. F. Osorio Tafall, coll. (13) Cenote de las Abejas, 1art, 16 Apr 1973, D. M. and S. M., coll. (14) Cueva de San Isidro, 4art*, 21 Mar 1973, J. R. R. and S. M., coll.; 1art, 29 Mar 1973, J. R. R., coll. (16) Pozo (=Cenote) de Santa Elena, 5 km S Telchac Puerto, 1art, 2art, 22 Mar 1973, S. M., coll. (17) Cenote de Hoctún, 29, Mar 1969, Terry Raines, coll.; 3art, 16 Mar 1973, J. R. R. et al., coll.; 1art, 29 Apr 1973, J. R. R. and R. W. M., coll; 2art*, 8 Aug 1973, Francis E. Abernethy, Deborah Denson, Masaharu Kawakatsu, R. W. M., R. W. Mitchell, Jr., S. A. M., and S. R. M., coll. (26) “Cenote X-ebiz, Hoctún,” 1art*, 26 Apr 1971, E. H. Sallee, coll. (See Map 2 and appendix table for distribution and shrimp associates.)

SIZE.—The largest male examined has a carapace length of 14.0 mm, that of the largest female is 18.6 mm.

REMARKS.—Holthuis (1956:57) reviewed available information on the biology of this species, indicating that it “lives in fresh subterranean waters. The temperature of the water of some of the caves varied between 23°8 and 26°8 C., the pH between 6.8 and 7.4, the contents of dissolved oxygen between 0.57 and 4.56 cc per liter, the salinity between 0.05 and 0.33 grams NaCl per liter.” He repeated the observations of Creaser (1936) that not only have they been observed crawling over the bottom but also they are “swift swimmers and are extremely sensitive to vibrations in the water.” The latter also indicated that in their stomachs were found chitinous elements, among which was a small claw of the same species.

FIGURE 7.—Creaseria morleyi (from Grutas de Tzab-Nah, 2 km S of Tecoh, Yucatán; all appendages from left side; a–o, male; p,q, female): a, dorsal view of anterior region; b, lateral view of carapace; c, lateral view of abdomen; d, antennule; e, antenna, basal portion and scale; f, mandible; g, first maxilla; h, second maxilla; i, first maxilliped; j, second maxilliped; k, first pleopod; l, second pleopod; m, appendices interna and masculina; n, telson and uropods; o, posterior region of telson; p, first pleopod; q, second pleopod. (Scales in mm.)

FIGURE 8.—Creaseria morleyi (from Grutas de Tzab-Nah, 2 km S of Tecoh, Yucatán; all appendages from left side of male); a, third maxilliped; b–f, first through fifth pereiopods, respectively; g, chela of first pereiopod; h, basal podomeres of fifth pereiopod with spermatophore emerging from base of coxa. (Scale in mm.)

Appendix

Summary of Distribution

Troglobitic shrimp fauna of the Yucatán Peninsula

MAP 1.—Range of the genus Typhlatya in Campeche and Yucatán. (Numbers adjacent to localities refer to caves listed in appendix table.)

MAP 2.—Range of Creaseria morleyi. (Numbers adjacent to localities refer to caves listed in appendix table.)

Literature Cited

Andrews, E. Wyllys, IV

1970. Balankanche, Throne of the Tiger Priest. xi + 182 pages, 60 figures, 2 plates. New Orleans: Tulane University, Middle American Research Institute.

Anonymous

1947. Expeditión Científica a Yucatán. Ciencia, 8(4–5):128–129.

Argano, Roberto

1972. On a Troglobitic Cyathura from Subterranean Waters of Mexico. (Crustacea, Isopoda). Quaderni Accademia Nazionale dei Lincei, 171:23–34, 3 figures.

Balss, Heinrich

1955. Decapoda, VI: Ökologie, Pages 1285–1367 in number 12 in book 7 in part I in volume 7 of H. G. Bronn’s Klassen und Ordnungen des Tierreichs, Figures 1043–1069.

Botosaneanu, L., and L. B. Holthuis

1970. Subterranean Shrimps from Cuba (Crustacea Decapoda Natantia). Travaux de L’Institut de Spéologie, “Emile Racovitza,” 9:121–133, 2 figures.

Cárdenas Figueroa, M.

1950. Informe Hidrobiológico y Faunístico de Yucatán. In Los Recursos Naturales de Yucatán. Boletin de la Sociedad Mexicana de Geografía y Estadística, 69(3):135–159, 5 figures.

Carreño, Alfonso de la O.

1950. Preámbulo. In Los Recursos Naturales de Yucatán. Boletin de la Sociedad Mexicana de Geografía y Estadística, 69(3):21–26.

Cendrero, Luis, editor

1971. Zoologia Hispanoamericana: Invertebrados. xxxi + 1151 pages. Mexico, D. F.: Editorial Porrúa, S.A.

Chace, Fenner A., Jr.

1942. A New Cave Shrimp from Cuba. Proceedings of the New England Zoological Club, 19:99–102, plate 29.

1943. Two New Blind Prawns from Cuba with a Synopsis of the Subterranean Caridea of America. Proceedings of the New England Zoological Club, 22:25–40, plates 5–7.

1954. Two New Subterranean Shrimps (Decapoda: Caridea) from Florida and the West Indies, with a Revised Key to the American Species. Journal of the Washington Academy of Sciences, 44(10):318–324, 2 figures.

1972. The Shrimps of the Smithsonian-Bredin Caribbean Expeditions with a Summary of the West Indian Shallow-water Species (Crustacea: Decapoda: Natantia). Smithsonian Contributions to Zoology, 98: x + 179 pages, 61 figures.

Chace, Fenner A., Jr., and Horton H. Hobbs, Jr.

1969. The Freshwater and Terrestrial Decapod Crustaceans of the West Indies with Special Reference to Dominica. United States National Museum Bulletin, 292: 258 pages, 76 figures.

Chace, Fenner A., Jr., and Raymond B. Manning

1972. Two New Caridean Shrimps, One Representing a New Family, from Marine Pools on Ascension Island (Crustacea: Decapoda: Natantia). Smithsonian Contributions to Zoology, 131: 18 pages, 11 figures.

Creaser, E. P.

1936. Crustaceans from Yucatan. In A. S. Pearse, E. P. Creaser, and F. G. Hall, The Cenotes of Yucatan: A Zoological and Hydrographic Survey. Carnegie Institution of Washington Publications, 457:117–132, 43 figures.

1938. Larger Cave Crustacea of the Yucatan Peninsula. In A. S. Pearse, editor, Fauna of the Caves of Yucatan. Carnegie Institution of Washington Publications, 491:159–164, 8 figures.

Croizat, Leon, Gareth Nelson, and Donn Eric Rosen

1974. Centers of Origin and Related Concepts. Systematic Zoology, 23(2):265–287, 2 figures.

Holthuis, L. B.

1950. Subfamily Palaemoninae, Part I in The Palaemonidae Collected by the Siboga and Snellius Expeditions with Remarks on Other Species, part X in The Decapoda of the Siboga Expedition, monograph 39a⁹ in Siboga-Expeditie. 268 pages, 52 figures.

1952. The Subfamily Palaemoninae. Part II in A General Revision of the Palaemonidae (Crustacea Decapoda Natantia) of the Americas. Allan Hancock Foundation Occasional Papers, 12:1–396. 1 figure, 55 plates.

1955. The Recent Genera of the Caridean and Stenopodidean Shrimps (Class Crustacea, Order Decapoda, Supersection Natantia) with Keys for Their Determination. Zoologische Verhandelingen Uitgegeven door het Rijksmuseum van Natuurlijke Historie te Leiden, 26:1–157, 105 figures.

1956. An Enumeration of the Crustacea Decapoda Natantia Inhabiting Subterranean Waters. Vie et Milieu, 7(1):43–76.

1974. Bithynops luscus, a New Genus and Species of Cavernicolous Shrimp from Mexico (Crustacea Decapoda, Palaemonidae). Quaderni Accademia Nazionale dei Lincei, 171:135–142, 2 figures.

Maccagno, T. Paulucci, and B. Cucchiari

1957. Revisione delle Palaemoninae del Museo di Torino. Bollettino dell’Instituto e Museo di Zoologia della Università di Torino, 5(11):201–369, 47 figures.

Monod, Théodore

1975. Sur la distribution de quelques crustacés malacostraces d’eau douce ou saumâtre. Mémoires du Muséum National d’Histoire Naturelle, series A (Zoologie), 88:98–105, 2 figures.

Monod, Théodore, and Philippe Cals

1970. Sur une espece nouvelle de crevette cavernicole: Typhlatya galapagensis (Decapoda Natantia; Atyidae). Mission Zoologique Belge aux Iles Galapagos et en Ecuador, 2:57–103, 67 figures.

Nicholas, Brother G.

1962. Checklist of Troglobitic Organisms of Middle America. American Midland Naturalist, 68:165–188.

Parzefall, Jakob, and Horst Wilkens

1972. Artbildung bei Höhlenfischen: Vergleichende Untersuchungen an zwei amerikanischen Synbranchiden (Pisces, Teleostei). Zeitschrift für Morphologie und Ökologie der Tiere, 73:63–79, 5 figures.

Pearse, A. S.

1936. Results of Survey of the Cenotes in Yucatan. Carnegie Institution of Washington Publications, 457:17–28, 2 plates.

1938. Introduction. In A. S. Pearse, editor, Fauna of the Caves of Yucatan. Carnegie Institution of Washington Publications, 491:1–17, 8 figures.

1945. La Fauna. Pages 109–271 in volume 1 of Enciclopedia Yucatanense. Illustrated.

Peck, Stewart B.

1974. The Invertebrate Fauna of Tropical American Caves, Part II: Puerto Rico, an Ecological and Zoogeographic Analysis. Biotropica, 6(1):14–51, 8 figures.

Reddell, James R.

1971. A Preliminary Biblography of Mexican Cave Biology with a Checklist of Published Records. Association for Mexican Cave Studies Bulletin, 3: 184 pages.

Rioja, Enrique

1953. Los Crustáceos Cavernícolas de México. Pages 285–298 in volume 7 (Ciencias Biológicas) of Memoria del Congreso Científico Mexicano. Mexico, D.F.: U.N.A.M.

1962. Caracteres Biogeográficos de México y de Centro America. Revista de la Sociedad Mexicana de Historia Natural, 23:27–50.

1971. Class IV: Los Crustáceos (Crustacea). Pages 470–554 in Luis Cendrero, editor, Zoología Hispanoamericana: Invertebrados. Mexico, D. F.: Editorial Porrúa, S. A.

Rodríguez de la Cruz R., M.

1965. I, Contribución al Conocimiento de los Palemonidos de México: II, Palemonidos del Atlántico y Vertiente Oriental de México con Descripción de dos Especies Nuevas. Anales del lnstituto Nacional de Investigaciones Biológico-Pesqueras, 1:73–112, 8 plates.

Silva Taboada, Gilberto

1974. Sinopsis de la Espeleofauna Cubana. Academia de Ciencias de Cuba, Serie Espeleológica y Carsológica, 43:1–65.

Straskraba, M.

1969. Lista de los Crustáceos Dulceacuícolas de Cuba y sus Relaciones Zoogeográficas. Academia de Ciencias de Cuba, Instituto de Biologia, Serie Biológica, 8:1–37.

Vandel, Albert

1964. Biospeologie: La Biologic des animaux cavernicoles. xviii + 619 pages, 80 figures, 11 plates. Paris: Gauthier-Villars.

1965. Biospeleology: The Biology of Cavernicolous Animals. Translated into English by B. E. Freeman. v–xxiv + 524 pages, 80 figures, 11 plates. New York: Pergamon Press.

Villalobos, Alejandro

1951. Un Nuevo Misidáceo de las Grutas de Quintero en el Estado de Tamaulipas. Anales del lnstituto de Biología, Universidad Nacional Autónoma de México, 22(1):191–218, 14 figures.

Wilkens, Horst

1973a. Ancienneté phylogénique et degrés de réduction chez les animaux cavernicoles. Annales de Spéléologie, 28(2):327–330, 3 figures.

1973b. Phylogenetic Age and Degree of Reduction of Cave Animals. Pages 203–206 in J. H. Schröder, Genetics and Mutagenesis of Fish. New York: Springer-Verlag, 356 pages.

1937c. Über das phylogenetische Alter von Hohlentieren. Untersuchungen über die cavernicole Süsswasserfauna Yucatans. Zeitschrift für zoologische Systematik und Evolutionsforschung, 11(1):49–60, 4 figures.

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