88 SMITHSONIA CNONTRIBUTION TS POALEOBIOLOGY Diagnostic Characters. —Test wall microperforate; aper¬ Stable Isotopes. —Biogeographic and stable isotopic data ture marked by a thin lip. Apertural position and height suggest an open-ocean, warm shallow-water habitat for W. somewhat variable. Biserial portion of test distinctly twisted, hornerstownensis ,similar to that of W .claytonensis (D’Hondt although less so than W claytonensis. Woodringina horner- and Keller, 1991; Liu and Olsson, 1992; D’Hondt and Zachos, stownensis distinguished from W. claytonensis by “the elon¬ 199 3. ) gate tapering test and the almost straight sutures” (Olsson, Stratigraphic Range. —Zone Pa to Zone P3b. 1960:29). Woodringina hornerstownensis often with six or Global Distribution. —Widespread in high and low more pairs of biserial chambers, whereas W claytonensis latitude s(Figur e34). usually limited to five or fewer. Origin of Species. —This species is generally considered to DISCUSSION .—The holotype illustration and description of have descended from Guembelitria cretacea via W .claytonen¬ Chiloguembelina taurica Morozova ,1961 ,closely resembles sis (Olsson, 1970, 1982; Smit, 1977, 1982; D’Hondt, 1991; Li W hornerstownsis Olsson ,1960 .Chiloguembelina taurica was and Radford, 1991; Olsson et al., 1992; Liu and Olsson, 1992). originally described as being characterized by a “high narrow Repository. —Holotype (USNM 626457) deposited in the test, weakly compressed bilaterally, its height two to three Cushman Collection, National Museum of Natural History. times the width. Lateral outlines at first subtriangular, later Unfigured paratypes deposited at Princeton University (No. almost parallel” (Morozova, 1961:18). The test of C. taurica is 81038) and Rutgers University (No. 5026). All specimens formed of 10-12 spheroidal chambers, and its intercameral examined by SD, CL, and RKO. sutures are almos tstraight .Although no tvisible in the holotype illustrations, the aperture of C. taurica was described as semicircular and basal (Morozova, 1961). Based on its type Family Chiloguembelinidae Reiss, 1963 illustration and description, Chiloguembelina taurica Mo¬ rozova ,1961 ,should be considered a possible junior synonym (by S. D’Hondt and B.T. Huber) o fWoodringina hornerstownensis Olsson ,1960 .The holotype Original Description. —“Trochospirally coiled with two illustrations and descriptions o fHeterohelix gradata Khalilov, chambers per coil arranged around an elongated axis. Test 1967, and Heterohelix gradata normalis Khalilov, 1967, also usuall ytwisted A. perture single a, n interiomargina al symmetri¬ closel yresemble Woodringina hornerstownensi sOlsson 1, 961. cal low to high arch, bordered by an asymmetrically situated Heterohelix gradata normalis was originally described as being characterized by an elongate “wedge-shaped [test], flap which is often protruding and platelike, or terminal, graduall ybroadening toward th eobliquel ytrimmed-of fapertu¬ situated on a shor tneck .No distinc ttoothplates .Ornamentation ra lend .. .chambers biserially arranged ,in each offset row there if present consisting of inflational papillae or short spines.” are 6-8 spherical chambers. ... Aperture semilunate, much (Rues s1,963:55.) shifted from the median frontal position and shielded on one Diagnostic Characters. —Small test comprised of biseri¬ side by a moderately protruding lip” (Khalilov, 1967:173). ally arranged chambers, often with a slightly twisted coiling From this description H .gradata normalis is indistinguishable axis. Intercameral sutures distinct, depressed, and often from W .hornerstownensi sin genera ltes tmorphology .Further¬ somewhat oblique .Wal lcalcareous and microperforate with more ,it appears to share the asymmetry o fapertura lshape and smooth to pustulous surface texture .Aperture arched ,rimmed position that is diagnostic of Woodringina and related taxa. by narrow lip, and generally infolded on one side of ultimate Heterohelix gradata sensu stricto was distinguished from H. chamber .Many Chiloguembelina species with well-developed gradata normalis by its last 4-10 chambers being much larger flap or flange bordering aperture along infolded side. than the preceding chambers (Khalilov ,1967). It also appears Discussion. —As noted in the discussion of the Guembe- to share the chamber shape ,adult chamber arrangement ,and litriidae ,the Chiloguembelinidae appears to be a monophyletic apertural asymmetry of W. hornerstownensis. Given the or paraphyletic family descended from Guembelitria cretacea genera lcongruence of their origina lillustrations and descrip¬ via Woodringina claytonensis (Olsson, 1970, 1982; Premoli tions with W .hornerstownensis ,Heterohelix gradata Khalilov Silva, 1977; Smit, 1982; D’Hondt, 1991; Li and Radford, 1991; and H. gradata normalis Khalilov should be considered Liu and Olsson, 1992; Olsson et al., 1992). It is generally possible junior synonyms of W. hornerstownensis Olsson, believed that this family was monophyletic throughout the 1960. The original descriptions of H. gradata and H. gradata Paleocene. It’s post-Paleocene status is less clear, as the normalis stated that the tests of these taxa are covered with relationships of Chiloguembelina to such late Paleogene and large pores (Khalilov, 1967). If so, these taxa are distinguish¬ Neogene taxa as Streptochilus Bronnimann and Resig, 1971, able from W. hornerstownensis on the basis of wall structure. and Cassigerinella Pokorny ,1955 ,is presently uncertain. Close examination of wall structure and other relevant Reiss (1963) originally assigned both Chiloguembelina and characters (i.e. ,the presence or absence of initia ltriseriality) in Zeauvigerina to the Chiloguembelinidae. Given the Late type populations of H. gradata and H. gradata normalis are Cretaceous occurrence of Zeauvigerina (Huber and Boersma, necessary to conclusively define the taxonomic status of these 1994 )and the earlies tPaleocene derivation o fChiloguembelina taxa relative to W .hornerstownensis. from a guembelitriid ancestor, retention of this assignment NUMBE 8R5 89 180°W 135°W 90°W 45°W 45°E 90°E FIGU R3E4.—Paleobiogeograph mic asphowi ndgistributi oWnfoodringi nhaornerstownen sOislss Zoionnes P tI oP3. would rende rthe Chiloguembelinidae a polyphyletic group .On midwayensis and closely related taxa (C .morse iand C .crinita). these grounds ,Zeauvigerina should no longer be assigned to This flap is located on the apertural side that is not infolded and tChheiloguembelinidae. results from extension of the apertural lip (and its trailing chamber wall) over the preceding chamber. The apertural infolding and opposing flap render the chiloguembelinid Genus Chiloguembelina Loeblich and Tappan, 1956 aperture distinctly asymmetric with respect to the plane of biserial symmetry. This apertural asymmetry and twisting of TYPE Species .—Chiloguembelina midwayensis (Cushman, the coiling axis are much reduced in the late Paleocene taxa 1940). Chiloguembelina trinitatensis (Cushman and Renz ,1942) and Original Description. —“Test free, flaring; inflated cham¬ Chiloguembelina wilcoxensis (Cushman and Ponton, 1932). bers biserially arranged ,with a tendency to become somewhat Apertural asymmetry is variably expressed in C. wilcoxensis; twisted; sutures distinct, depressed; wall calcareous, finely although apertural asymmetry occurs in early ontogeny, the perforate ,radia lin structure ,surface smooth to hispid ;aperture apertures o ftermina lchambers appear to be symmetric in some a broad low arch bordered with a pronounced neck-like C. wilcoxensis specimens and asymmetric in others (Plate 70: extension of the chamber; commonly this forms a more Figures 11, 12, 16, 17). strongly developed flap a tone side ,so tha tthe aperture appears DISCUSSION —. Th emicroperforat esurfac etexture a, pertural to be directed toward one of the flat sides of the test.” (Loeblich asymmetry, and twisted coiling axis are the primary features an dTappan 1, 956:340.) that unite Chiloguembelina species with woodringinids and Diagnostic Characters. —The original description is other Paleocene descendants of Guembelitria cretacea. The diagnostic o fmany Chiloguembelina species (i.e. ,Chiloguem¬ biserial first whorl of Chiloguembelina species distinguishes belina midwayensis (Cushman, 1940), C. crinita (Glaessner, them from Woodringin aspecies. 1937b), and C. morsei (Kline, 1943)). The diagnostic charac¬ Beckmann (1957) proposed that Giimbelina trinitatensis ters of Chiloguembelina species include the microperforate Cushman and Renz and Giimbelina wilcoxensis Cushman and surface texture ,slight twisting of the coiling axis ,and infolding Ponton descended from Chiloguembelina crinita (Glaessner). of the apertural lip on one side. The apertural flap noted by On this basis, Beckmann (1957) assigned trinitatensis and Loeblich and Tappan (1956) and Reiss (1963) characterizes C. wilcoxensi sto the genu sChiloguembelina. 90 SMITHSONIA CNONTRIBUTION TS POALEOBIOLOGY Chiloguembelina crinita (Glaessner ,1937) Chiloguembelina midwayensis (Cushman ,1940) Plate 69 :figure s1-8 Figure 35 ;Plate 13 :figures 9 ,10 ,12 ,13 ;Plate 69 :figures 16-22 Giimbelin acrinit aGlaessne r1,937b:38 3p, 4i .f:ig 3.4a, b[Paleocene b,eds Giimbelin ma idwayens Cisushma n1,940:6 5p 1,i .1fi: g1 [-5Paleocen eS,umter fr oGmoijatsc Khlijjutsch]. Co A., labama].—Cushma nan dTodd 1,946:5 8p, 1i.0 f:ig 1. 5[Paleocene, Chiloguembeli ncarin i(tGalaessner).—Beckman 1n9,57:8 t9e,xt-fig 1s4. Arkansas],—Cushman 1,951:37 p, 1i.1 f:ig s7 .8[,Paleocene A, labama, (1-4 )p, i2.1 f:ig 4.a, bG[ loborotali apseudomenard iain dGloborotalia Arkans a Tnse,dxas], velascoensis Zones (Zones P4 and P5) ,lowe rLizard Springs Fm., Chiloguembel imnaidwayen (sCisushman).—Loeb lai cTnhadpp a1n95, 71a7:9, Trinidad].—Loeblich and Tappan ,1957a :178 ,pi .49 :fig .1 [upper p i4. 1 f:ig 3.[Danian C, layton Fm .A, labama] p, i4. 3 f:ig 7. a,b [Will sPoint Paleocene H, omerstow nFm N., e wJersey ]p, 5i.1 f:ig sla, - 3[Vincentown Fm .T,exas ]p, i4.5 f:ig 9.a, b[Porter sCree kClay A, labama].—D’Hondt, Fm. ,New Jersey] ,pi .56 :fig .la,b [Aquia Fm. ,Maryland] ,pi .60 :fig .6 1991:173 p, i2. f:ig 1. 3[Zon ePa D, SDP Sit e528/31/CC 1: 4-1 5cm W; alvis [Nanafal iFam A.,labama p] ,6i. 2f:i g[1V. elasc Fom M., exico],—MacLeod, Ridge S,out hAtlanti cOcean ]f,ig 1. 4[Zon ePa D, SD PSit e577/12/5 3:4-36 1993:66 p, i6. f:igs 1. ,2 5, 6,[lowe rZon eP6 O, DP Hol e738C/10R/4 3: 4-36 cm S;hatsk Ryis en,orthwester Pnacif iOc cean []N, o Ot lsso n1,970:60 1p,i. cm K;erguele Pnlatea us,outher Inndia Oncean []N, o Htube 1r,99 b1:44 8p,i. 91 f:ig 8..—MacLeod 1,993:66 p, i6 .f:igs 3 .4 ,7,-10.—Hube arn dBoersma, 6 :figs .2 ,3 ;1991c:461 ,pi .2 :figs .3 ,4.] 1994:282 p, i3 .f:ig 3.a-d.] Chiloguembe mliniadwaye nmsidswaye n(Csiusshman).—Beckmann, Original Description. —“Test small, built up with about 1957:90 t,ext-fig 1. 4(24-27 )p, i2.1 f:ig l.a, bG[ loborotali atrinidadensis 10-15 spherica lor oval-shaped ,distinct ,separated chambers. throug hGloborotali avelascoens iZsone slo, we Lrizar dSpring Fsm., The spire of the initial chambers in existing specimens is not Trinidad]. distinctly recognizable. The ratio of chamber width to the Chiloguembel imnaidwayen stirsombiform Biesckma n1n9,57: 9te0x, t- f1ig4. length varies strongly .The largest diameter o fthe last chamber (28-31 p) ,2i. 1fi: g6.a -[cGloborotal ipaseudomenard aiin Gdloborotalia is offse tfrom the biseria lplane .Consequently ,the las tchamber velascoens Zisone lso,w eLriza rSdprin gFsm T.r, inidad]. diagonally overlies the previous one ,the median suture on both Original Description. —“Test small, compressed, usually sides are not opposite each other and the test appears thereby twice as long as broad, rapidly tapering, with the greatest somewhat distorted .The aperture opens not in the usua lcase breadth formed by the las tpair o fchambers ,periphery rounded towards the edge of the test, but in a direction which lies throughout ,lobulate ;chambers with breadth and heigh tabout between the edge and the side of the test .In extreme cases ,it is equal, slightly overlapping, inflated, increasing rapidly in directed even along the suture of the last chamber in side view. height as added; sutures distinct, depressed, very slightly The aperture is moderate in width ,but high ,half rounded and curved ,wal lfinely spinose ;aperture high ,arched ,with distinct enclosed along the margin .The test surface in many specimens lateral flanges [sic]. Length 0.18-0.22 mm.; breadth 0.10-0.12 is covered by fine granulations ,but in spite of their minuteness mm. ;thickness 0.05 mm.” (Cushman ,1940:65.) especially on the periphery ,[there are] distinctly visible sharp Diagnostic Characters. —Test small, compressed in t ipnryotuberances. thickness (depth), and rapidly tapering. Early chambers “Measurements.—length 0.17-0.22 mm.; width 0.10-0.15 subspherical, successive chambers increase more rapidly in mm.; thickness 0.05-0.1 mm.” (Glaessner, 1937b:383; trans¬ breadth than in height .Late-stage chambers cross the coiling late dfrom German.) axis and overlap immediately preceding chamber .In holotype, Diagnostic Characters. —Test biserial throughout, overlap so pronounced tha tmaximum breadth o ffina lchamber exhibiting characteristi chiloguembelinid apertura al symme¬ nearly equal to maximum breadth of test (Plate 13: Figures 9, try; aperture marked by narrow lip, infolded on one side, and 10) .Holotype’s surface covered with numerous smal lpustules; expanded into distinct apertural flange on opposite side. As however ,last two chambers contain few pustules .Contrary to noted by Beckmann (1957) and Loeblich and Tappan (1957a), the original description, aperture of each chamber with only later chambers subglobular .Sutures distinct and depressed. one distinct lateral flange (the chiloguembelinid “flap” of Tes tmicroperforate and las tchambers finely hispid. Loeblich and Tappan, 1956) (Plate 69: Figures 16-22). DISCUSSION .—The late rchamber so fChiloguembelina crin¬ DISCUSSION .— Chiloguembelina midwayensis strombi¬ ita specimens are much higher and more inflated than those of formis Beckman ,1957 ,was erected as a Paleocene subspecies C. midwayensis and C. morsei. These differences are readily of Chiloguembelina midwayensis (Cushman, 1940). The observable, as late-stage chambers of C. crinita appear chambers o fthe C .midwayensis strombiformis holotype (Plate subglobular in edge and plan views. 13: Figures 12, 13) expand much more rapidly in depth Stable Isotopes.—-N o data available. (thickness) than do those of C. midwayensis sensu stricto; in Stratigraphic Range. —Lower Zone P4 to lower Zone P6. late-stage chambers o fC .midwayensis sensu stricto ,chamber Global Distribution. —Cosmopolitan. breadt hconsistentl yexceed schambe rdepth. ORIGIN OF Species.— Chiloguembelina crinita is believed to Stable Isotopes. —The stable isotopic signature of C. have evolved from C .midwayensis (Beckmann ,1957). midwayensis suggests that this species inhabited a deeper- Repository. —Holotype deposited in the Collections of the water or cooler-season habitat than most co-occurring taxa Institute for Fuel-Research of the Academy of the Sciences of (Boersma and Premoli Silva, 1983; D’Hondt and Zachos, Russia (Paleontology Division) ,Moscow. 1993). NUMBE 8R5 91 FIGU R3E5.—Paleobiogeograph mic asphowi ndgistribut i Conhf iloguembeli nmaidwayen s(Cisushm a tinh)e Danian “.s.l .r”efer ts osens ulat oform fsoun da htig hlatitud esites. Stratigraphic Range. —Zone Pa (D’Hondt, 1991) to as broad ,regularly tapering ,with greatest breadth at apertural Zone P5 (Beckman ,1957; Boersma ,1984b). end ,periphery rounded and lobulate; chambers with breadth GLOBAL Distribution. —Chiloguembelina midwayensis greater than height, inflated, increasing rapidly in size, occurred at low and middle latitudes (Beckmann, 1957; especially in breadth; sutures distinct, depressed; wall finely Boersma, 1984b; D’Hondt and Keller, 1991; Liu and Olsson, but distinctly spinose; aperture high, arched, with distinct 1992 )(Figure 35). lateral flanges [sic].” (Kline, 1943:44.) ORIGIN of Species. —Chiloguembelina midwayensis Diagnostic Characters. —Test biserial throughout. Su¬ evolved from C. morsei (Kline) (D’Hondt, 1991). tures distinct and depressed ;basa lsutures separating earliest Repository. —Holotype (USNM CC35715) deposited in chambers subhorizontal, those separating later chambers the Cushman Collection ,Nationa lMuseum of Natura lHistory. oblique. Successive chambers overlap, particularly in late Examined by SD, BTH, CL, and RKO. ontogeny. Initial chambers subspherical. Chamber breadth increases more rapidly than chamber depth, with successive Chiloguembelina morsei (Kline, 1943) chambers exhibiting a greater breadth to depth ratio than predecessor, consequently, maximum breadth of each late- Plate 13 :figures 14 ,15 ;Plate 69 :figures 9-15 stage chamber greater than its maximum depth. Surface of Gumbelin amorse Ki line 1,943:44 p, i7 .f:ig 1. 2[Danian P, orter sCree kClay, holotype tes tmarked by numerous smal lpustules ;pustules less Cl aC yoM.,ississippi]. abundant on final chambers. Aperture of each chamber Chiloguembelin ma ors e(Ki line).—Loeblic ahn Tdappa n1,957 a1:7 9p 4,i.0: exhibiting only one distinct latera lflange. fig .2a,b [Danian ,Erslev ,Mors ,Denmark] ,pi .41 :fig .4 [Clayton Fm., Alabama ]p, i4.2 f:ig l.a, b[Brightsea Ftm .M, aryland ]p, i4.3 f:ig 2[.Kincaid DISCUSSION .—The gross morphology o fChiloguembelina Fm. ,Texas] ,pi .43 :fig .6a,b [Wills Point Fm. ,Texas] .[Not Huber, morse iis very similar to that of Chiloguembelina midwayensis. 1991a:448 p, i6. f:igs 6. 7, .] Loeblich and Tappan (1957a) suggested that C. morsei can be Chiloguembeli nmaidwayen s(iCsushman).—MacLeo 1d9,93:6 pf6igi: ,.3s,. distinguished from C. midwayensis sensu stricto by the 4[Danian D, SD PHol e577A/12/2 4:4-4 6cm S;hatsk Ryise n,orthwestern former’s narrower test, more globular chambers, and more Pa Ocicfiecan], deeply constricted sutures. The two taxa are most readily Original Description. —“Test small, about twice as long distinguished by the narrowness of their tests ;the chambers of 92 SMITHSONIA CNONTRIBUTION TS POALEOBIOLOGY C. morsei expand less rapidly in breadth than those of C. deposited in the Cushman Collection, National Museum of midwayensis. Consequently, the periphery of the former Natural History. Examined by SD and BTH. defines a more acute angle (~50°) than that of the latter (~60°). Forms intermediate between C. morsei and C. midwayensis have been illustrated as C. midwayensis by D’Hondt Chiloguembelina trinitatensis (Cushman and Renz, 1942) (1991:173, pi. 2: figs. 13, 15). Plate 13 :figures 11 ,16 ;Plate 70 :figures 8-10 ,14 Stable Isotopes .—-No data available. Gumbelin atrinitatens iCsushma nan dRen z1,942: 8p, 2 if.:ig [8.Paleocene, Stratigraphic Range. —Zone Pa (D’Hondt, 1991) to Solda Fd mTor.i,nidad]. Subzone Pic (Boersma ,1984b). Chiloguembel itnrainitaten (sCisushm a Rnednz).—Beckma n1n9,57:91, Global Distribution. —Low and middle latitudes text-fig 1. 5(43-45) p, i2. 1 f:ig 7. a,b [Globorotali avelascoensi sZone, (Boersma, 1984b; D’Hondt and Keller, 1991). Liza rSdprin gFsm T.r,inidad]. ORIGIN o fSpecies.— Chiloguembelian morse ievolved from Original Description. —“Test slightly longer than broad, a Woodringina species in Zone Pa (D’Hondt, 1991; Liu and moderately compressed, rapidly tapering, greatest breadth Olsson 1,992). formed by the last-formed pai ro fchambers ,periphery rounded, Repository. —Holotype (USNM 487301) deposited in the lobulate; chambers with breadth and height about equal ,the Cushman Collection, National Museum of Natural History. last-formed pair in the adult usually much larger than the Examined by SD, BTH, and RKO. remainder of the test; sutures distinct, depressed, straight, nearly at right angles to the elongate axis; wall smooth or slightly hispid ,aperture high ,arched .Length of holotype 0.27 Chiloguembelina subtriangularis Beckmann ,1957 mm; breadth 0.20 mm; thickness 0.15 mm.” (Cushman and Plate 13 :figures 17 ,18 ;Plate 70 :figures 1-7 Renz 1,942:8.) Diagnostic Characters. —Distinguished by biserial test Chiloguembeli nsaubtriangula rBiseckman 1n9,57:9 t1e,xt-f i1(g35.9-4 2p)i,. 21 f:ig 5.a, b[Paleocene G, loborotali apusill apusill aZone l,owe Lrizard with chambers increasing uniformly in breadth and height ,and Springs Fm. ,Trinidad].—Said and Kerdany ,1961:331 ,pi .2 :fig .6 symmetrically centered ,low-arched aperture surrounded by [Paleocen elo, we pra ro tEfsn Sahal eF,arafr Oa asi sE,gypt], narrow e,quidimensiona lilp. Discussion. —The holotype of this species differs from C. Original Description. —“Test small, subtriangular, crinita by having an aperture that is symmetrically positioned pointed at the base ,compressed ,with a subangular periphery. Chambers biserial, very slightly inflated. Sutures nearly on the chamber face, and it differs from C. wilcoxensis by itssmaller size and slower, more continuous chamber-size horizontal ,slightly depressed ,at least in the later stages. Wall smooth .Aperture commonly slightly eccentric ,semicircula rto increase .The holotype has been extensively recrystallized sothe primary wall texture is difficult to discern. subquadrangular, may have a slight collar.” (Beckmann, Stable Isotopes.—N o data available. 1957:91.) Stratigraphic Range. —Zone P5 to lower Zone P6a. In Diagnostic Characters. —Test small, biserial with a subangular periphery ,subtriangular in side view. Chambers Trinidad ,Beckman (1957) recorded C. trinitatensis only in theMorozovella velascoensis Zone (= Zone P5) ,but observations increasing nearly twice as rapidly in breadth than in height, by BTH suggest it ranges from Zone P5 to Zone P6a at DSDP slightly inflated, successive chambers slightly overlapping Sit e152. previous chambers ,sutures somewhat depressed and nearly straight, forming a low angle with the growth axis. Aperture a Global Distribution. —Reported primarily from low-latitude n, ear-shor emarin esections. low, asymmetrically positioned, interiomarginal arch sur¬ rounded by a lip that narrows toward center o fchamber .Length Origin of Species. —Beckmann (1957) suggested that C. 140-22 0pm. trinitatensis descended from C. crinita during the Paleocene,bu tsee discussion under C .wilcoxensis. DISCUSSION. —This species is easily distinguished from other chiloguembelinids by its subtriangular test with a Repository. —Holotype (USNM CC38198) deposited in subangu plaerriphery. the Cushman Collection ,Nationa lMuseum of Natura lHistory. Stable Isotopes.—N o data available. Examined by BTH. Stratigraphic Range. —Zone Pic to Zone P3. Global Distribution. —Reported from the low to middle Chiloguembelina wilcoxensis (Cushman and Ponton, 1932) latitud ewsorldwide. Plate 13 :figures 19 ,20 ;Plate 70 :figures 11-13,15-18 ORIGIN of Species. —Beckmann (1957) suggested that C. subtriangularis descended from C. midwayensis during the Giimbelin awilcoxensi sCushma nan dPonton 1, 932:66 p, i8. f:igs 1. 6 1, 7 Paleocene. [low eErocen eW, ilco Fxm O.,zar kA,labama],Chiloguembe lwinialcoxen (sCius shm a aPnnodnton).—Beckma n19n5, 7:92, REPOSITORY .—Holotype (USNM P5783) ,figured paratypes text-fig .15 (49-58) ,pi .21 :figs .10 ,12 ,13 [uppe rPaleocene to lower (USNM P5784A-D), and unfigured paratypes (USNM P5785) Eocene L,izar dSpring sFm .T,rinidad].—Hube r1,99 1b:440 p, i6 .f:igs 4 .5, NUMBE 8R5 93 [Zon eAP6a e,arl yEocene O, D PHol e738C/8R 2:64.3 5mbs fK; erguelen from C. trinitatensis during the late Paleocene because C. Plate asuo,uthe Irnnd iOancean]. wilcoxensis and C. trinitatensis are more similar morphologi¬ Original Description. —“Test biserial, periphery broadly cally, and the study of Caribbean DSDP Site 152 indicates that rounded; chambers distinct, much inflated, increasing very the first occurrence of C. trinitatensis is older than that of C. rapidly in the adult so that the last four chambers make up a wilcoxensis (B. Huber, pers. observ., 1995). Both species have very considerable amount of the entire test; sutures distinct, a similar pustulose wall texture suggesting that they are depressed ;wal ldistinctly papillate throughout ;aperture a low phylogenetically related (Plate 70 ,compare Figures 14 and 18). opening at the base of the last-formed chamber in the median REPOSITORY. —Holotype (USNM 16218) deposited in the line. Length 0.45 mm; breadth 0.35 mm; thickness 0.25 mm.” Cushman Collection, National Museum of Natural History. (Cushman and Ponton ,1932:66.) Examined by BTH. Diagnostic Characters. —Distinguished by large test size ,broadly rounded periphery ,rapid chamber-size increase in Family Heterohelicidae Cushman, 1927 initia lportion of test ,and symmetrically centered ,low-arched to semicircula raperture surrounded by an equidimensiona lip. (by B.T .Huber) DISCUSSION .—The fina lchamber in adul tChiloguembelina Original Description. —“Test in the more primitive forms wilcoxensis may be normalform to strongly kummerform .The planospiral in the young, later becoming biserial, in the more aperture on the final chamber may be a symmetrical low to specialized genera the spiral stage and even the biserial stage moderately high semicircular arch, centered on the chamber may be wanting and the relationships shown by other face ,and bordered by an equidimensiona llip (Plate 70 :Figures characters ;wal lcalcareous ,perforate ,ornamentation in higher 11, 12), or they may be slightly asymmetrical, off-centered on genera bilaterally symmetrical ;aperture when simple ,usually the fina lchamber face ,and bordered by an inequidimensional large for the size of the test, without teeth, in some forms with lip that is slightly infolded on one side (Plate 70: Figure 16). apertura lneck and phialine lip.” (Cushman ,1927:59.) The symmetrica lshape and positioning of the aperture and Diagnostic Characters. —Test with biserial arrangement equidimensional bordering lip on adult specimens of C. of alternating chambers ,fina larrangement either multiple or wilcoxensis are reminiscen to fthe Cretaceous Heterohelicidae. uniserial; chambers ,globular to ovoid in shape; wal lsmooth or Dissection of adult tests with symmetrical apertures in the striated with fine to coarse parallel ridges; aperture, a low, center of the fina lchamber ,however ,revea lthat the apertures symmetrica larch ,usually at base of ultimate chamber ,may be on pre-adult chambers are asymmetrica lin position and shape terminal ,may have accessory sutura lapertures. and the bordering lip is infolded on one side (Plate 70: Figure DISCUSSION .—Only simple ,biseria lforms survived into the 12). Apertural asymmetry in early ontogeny is taken to Cenozoic .The latter portion of the test often becomes uniserial. represen ta primitive feature shared with the chiloguembelinid stock, whereas apertural symmetry in adult specimens is considered a derived character that first appeared in C. Genus Rectoguembelina Cushman ,1932 trinitatensis. Chiloguembelina wilcoxensis differs from this Type Species .— Rectoguembelina cretacea Cushman ,1932. species by its larger ,less tapering test. Original Description. —“Test with the early chambers Stable Isotopes.—-N o data available. arranged in a biserial manner similar to Guembelina, later Stratigraphic Range. —Zone P4 to Zone P6a. The FAD chambers uniseria land rounded in transverse section ;cham¬ of C .wilcoxensis is not well-constrained in published deep-sea bers all inflated, distinct; sutures distinct, depressed; wall records because many authors have not differentiated the calcareous, thin, very finely perforate; aperture in the early chiloguembelind species. In Trinidad, Beckmann (1957) stages similar to Guembelina in the adult terminal, rounded, recorded the FAD of C. wilcoxensis in the Globorotalia with a distinct neck.” (Cushman ,1932:6.) pseudomenardii Zone (= Zone P4), with an uncertain occur¬ Diagnostic Characters. —Transition from biserial to rence within the lower part of this zone, and the LAD at the top uniseria lportion of test very abrupt ,occurring after first four or of the Globorotalia velascoensis Zone (= Zone P5). Observa¬ more pairs o fbiseria lchambers ,withou tan intervening interval tions by BTH of high-latitude samples from ODP Sites 698, o fgradually increasing chamber overlap .Apertures on biserial 700, and 738 indicate that the FAD of this species is in the portion interiomargina lwith a small ,narrow arch ;apertures on middle of Zone AP4 (~Zone P4) and its LAD in Zone AP6a uniseria lchambers terminal ,circular ,and aligned in rectilinear (~Zon Pe6a). fashion ,without lip or toothplate .Wal lcalcareous ,microperfo- Global Distribution. —Reported from low to high lati¬ rate ;surface smooth to finely pustulose. tud wesorldwide. Discussion. —Glaessner (1936) and Montanaro Gallitelli Origin of Species .—Although Beckmann (1957) suggested (1957) considered Rectoguembelina to be a junior synonym of that C. wilcoxensis descended from C. crinita during the late Tubitextularia Sulc (type species = Pseudotextularia bohemica Paleocene, it is more likely that C. wilcoxensis was derived Sulc, 1929), whereas Loeblich and Tappan (1964, 1988) 132 SMITHSONIA CNONTRIBUTION T SPOALEOBIOLOGY PLATE 13 USNM Primary Type Specimens (bar s=5 0pm) FIGUR 1E.— Rectogiimbelin caretace Caushma n1,93 2h,olotyp eU,SN MCC1630 8u;ppe Mr aastrichtian, Arkadelp hCial aHyo, pAer,kansas. FIGUR 2E.— Tubitextular ilaeviga tLaoeblic ahn Tdappa n1,95 (7R=ectoguembelin caretace Caushman), holotyp eU,SN MP582 0lo; we Praleocen eM, cBryd Leimeston Me b rC„layto Fnm W., ilco Cxo A.,labama. FIGUR 3E. —Guembelitr icaretace Caushma n1,93 3h,olotyp eU,SN MC 1C902 2u;pp eMraastrichtia nN,avarro F Tme.x,as. FIGUR E54S., —fVoodringin haomerstownens Oislsso n19, 6 h0,olotyp Ue,SN M62645 Z7;on Pe3 bH,omerstown Fm N.,e Jwersey. FIGURE 67S,.— Woodringin calaytonens iLsoeblic ahn Tdappa n1,95 7h,olotyp eU,SN MP568 5lo; we Dranian, Pin Bearre Mn b rC.,layto Fnm A.,labama. FIGUR 8E.— Woodringin kaelle Mri acLeo d1,99 (3W= oodringin calaytonens iLsoeblic ahn Tdappan Z);on Pea, DSD SPi t5e77A/12/ 24:4-4 c6m S;hatsk Ryis en,orthwester Pnacif iOccean. FIGURE 9S1,0.— Gumbelin ma idwayens iCsushman 1,94 0h,olotyp eU, SNM CC3571 5b;as aMl idwa Fym., Sum tC eAorl.a, bama. FIGURE 1S 1,6.— Gumbelin tarinitatens iCsushma ann Rden z1,94 2h,olotyp eU,SN MCC3819 8P;aleocene, Solda Fd moTr.i,nidad. FIGURE 1S 21,3.— Chiloguembelin ma idwayens isstrombiform iBseckman n1,95 (C7=hiloguembelina midwayen s(iCsushman )h)o, lotyp Ue,SN PM577 G1;loborota lpiaseudomenar dZioi n Lei,za rSdprin gFsm., Trinidad. FIGURE 1S 41,5.— Giimbelin amorse Kiline 1,94 3h,olotype U, SNM 487301 D; anian P,orter Csree Ckla yC,lay MCois.s, issippi. FIGUR E1 S178, . —Chiloguembelin saubtriangular Biseckman n19, 5 h7,olotyp Ue,SN MP578 G3;loborotalia pusil lpausil lZaon elo, we Lrizar Sdpring Fsm T.,rinidad. Figure 1s 92,0.— Giimbelin awilcoxens iCsushma nan dPonton 1,93 2h,olotype U, SNM 16218 W; ilco Fxm., O zAalarkb,ama. NUMB E8R5 133 244 SMITHSONIA CNONTRIBUTION TS POALEOBIOLOGY PLATE 69 Chiloguembelin acrinit a(Glaessner 1, 937) (Figure s1-7 :bar s= 50 pm ;Figure 8 :ba r= 10 pm) FIGURE S1-8.—Zon eP4 G, lendol aWel lN, ew Jersey s,ampl e230-23 2fee tF; igur e8 v,iew o 2fn dchambe or f Figu s r3heowin pgustulo swe atlelxture. Chiloguembelina morse i(Kline ,1943) (Figure s9-14 :bar s= 50 pm ;Figure 15 :ba r= 10 pm) FIGURE 9S1,0.—Danian O, D PHo l6e90C/14R/ 17:6-8 c0m M; au dRis eS,outher nOcean. FIGURE 1S1-15.—Zon Pe 2D, SD PSit 3e56/25/ 51:48-15 c0m S;a oPaul oPlateau S,out hAtlant iOc cean F;igure 1 5v,ie wo 3fr cdhambe o rsfpecime snhowin pgustulos we a tlel xture. Chiloguembelin amidwayensi s(Cushman 1,940) (Figure s16 1, 8-22 :bar s= 50 pm ;Figure 17 :ba r= 10 pm) FIGURE 1S6-22.—Zon Pe 2D, SD PSit 3e56/25/ 51:48-15 c0m S;a oPaul oPlateau S,out hAtlant iOc cean F;igure 1 7v,ie wo 3fr dchambe o rFfigur e1 s8howin gpustulos ewa tllexture. NUMBE 8R5 245 W* &C- l4»4 wI wmMmSmm fill 246 SMITHSONIA CNONTRIBUTION TS POALEOBIOLOGY PLATE 70 Chiloguembelin asubtriangulari sBeckmann 1, 957 (Figure s1-3 5, -7 :bar s= 50 (am ;Figure 4 :ba r= 10 (am) FIGURE S1-7.—Zon eP2 D, SD PSit e356/25/5 1:48-15 0cm S;a oPaul oPlateau S,out hAtlant iOc cean F;igure 4 v,iew o 2fn dchambe or Ffigur e7showin gpustulos ewa ltlexture. Chiloguembelina trinitatensis (Cushman and Renz ,1942) (Figure s8-10 b: ar s = 5jam F; igure 14 b: a r =2 0(am) FIGURE S8 9,.—Zon eP5 D, SD PSit e152/4/3 2:0-2 4cm. FIGURE S10 1, 4.—Zon eP5 D, SD PSit e152/4/2 1: 6-1 8cm C; aribbea nSea F; igur e14 v, iew o 3f r dchambe rof Figu r 1se0howin pgustulo swe atlelxture. Chiloguembelina wilcoxensi s(Cushman and Ponton ,1932) (Figure s11-13 1, 5-17 b: ar s =5 0(am F; igur e18 b: a r =2 0(am) FIGURE 1S —1 1 31,6-18.—Uppe Praleocen eO, D PHol e690B/16X/5 7:6-8 c0m M; au dRis eS,outher nOcean; Figur 1e 2d,issectio onFfigur 1e s1howin tgh aesymmetric aplositio onafperture iesnarlie frorme cdhambers; Figur e18 v,ie wo 2fn dchambe or Ffigur e1 7showin gpustulos ewa tllexture. FIGUR 1E5.—Hypotyp es,pecime inllustrate idBneckman n1,95 7p 2,i. 1fi: g1. 3lo; we Erocen ety, p Geloborotalia re Zxon eL,izar Sdpring Fsm T.,rinidad. NUMBE 8R5 247 i0cgq ItfllPP y-iV- _. ‘•'SV^v, D’Hondt, Steven and Huber, Brian T. 1999. "Family Chiloguembelinidae Reiss, 1963." Atlas of Paleocene planktonic foraminifera 85, 88–93. 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