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BASTERIA,69:121-144,2005 Anomalodesmata(Bivalvia) fromthe Surinamshelf, theCaribbeanregion Jørgen Knudsen ZoologicalMuseum,University ofCopenhagen,Universitetsparken15,DK2100 Copenhagen0, Denmark The present paper records 11 taxa of Anomalodesmata (Poromyidae, Cuspidariidae, Verticordiidae)from Surinam and adjacentwaters. One taxon(Cardiomyasurinamensis)was previously known from the area,and two (Cuspidarialuymesi and C. altenai)arenew species. The total distribution ofthe taxais outlined.Comparisonwiththe Anomalodesmata ofSaba Bankismade.Verticordia acuticostataisamphi-Atlantic,V.ornataisamphi-American.Themate- rial comprises 269 samplesfrom 95 stations, and consists of27live-collected specimens and some2000detached valves. The scarcityoflivespecimensmay bedue totheturbidwater and themovement ofbottomsediment. Keywords:Bivalvia,Anomalodesmata,Poromyidae,Cuspidariidae,Verticordiidae,taxonomy, biogeography,shelffauna, Caribbean,Surinam. INTRODUCTION ThepresentpaperdealswiththebivalvesofthesubclassAnomalodesmataDall, 1889, obtainedbythreesurveys oftheshelfofSurinamandtheadjacentareasofFrench Guyana (to52°50'W).Thestationsinvestigated were takenonlinesroughly atrightangles to the Vessel Year/Month Area No.of Depthrange stations inmetres H.NL.M.S.'Snellius' iii-v.1966 WesternshelfofSurinam, legsA-H 66 10-100 H.NL.M.S.'Luymes' iii-iv.1969 Eastern shelfofSurinam,legsA,I-N 66 5-940 H.NL.M.S.'Luymes' viii-ix.1970 FrenchGuyana 23 6-617 Surinam 20 BritishGuyana 72 Totals 247 5-940 Table 1.Samplesstudied. Family No.ofsamples No.ofspecies No.ofspecimens No.ofsinglevalves Poromyidae 57 1 8 627 Cuspidariidae 151 7 16 514 Verticordiidae 58 3 2 865 Totals 266 11 26 2006 Table 2.Summary ofthematerial ofAnomalodesmata. 122 BASTERIA, Vol.69, No. 4-6,2005 Fig. 1.StationsoperatedduringtheSurinamexpeditions 1966/70.Anomalodesmata were obtained atthe numbered stations. general coastlineand parallel toeachother; some stationswere workedmore than once. Besides biological sampling, the programme included geomorphology, sedimentology andhydrography. The stationsareshowninfig. 1;the95stationsyieldingAnomalodes- mataare numbered.Mostofthematerialwas collectedby the0.1m2van Veengrab. Additional samples from the U.S. National Museum, Smithsonian Institution, Washington, D.C. (NMNH), the Allan Hancock Foundation, Los Angeles, and the Zoological MuseumofCopenhagen (ZMUC) havealsobeenexamined.Thevariousexpe- ditionsare indicatedby thefollowing acronyms: OCPS (Onderzoek vanhetContinentale Plat van Suriname=Investigation of the ContinentalShelfofSurinam) and CICAR (an internationalventure: Cooperative Investigation ofthe Caribbeanand adjacentregions). Altena (1965, 1968, 1969, 1971a,b, 1975a,b) dealtwith the bivalves of the shelfof Surinam. The summarizing paper (1971b) enumerates 128 species of which 5 are Anomalodesmata:Lyonsia hyalina Conrad, 1831, Anticorbula sinuosa (Morrison, 1943), Periploma coquettae Altena, 1968,Cardiomya surinamensis Altena, 1971, Verticordia ornata (d'Orbigny, 1842).Thespecies listedwere foundasafewsingle valveseach. The present survey describes an extensive material, adding several species to the fauna: Poromyidae.-Poromya rostrataRehder, 1943 Cuspidariidae.- Cuspidaria luymesi spec. nov. (valves only); C. altenai spec, nov.; Cardiomya ornatissima (Orbigny, 1842); C. surinamensis Altena, 1971;Myonera lamellifera (Dall, 1881);M. paucistriata (Dall, 1881);Plectodoragranulatus (Dall, 1881). Verticordiidae.- Verticordia acuticostata (Philippi, 1844) (valves only); V. fischeriana (Dall, 1881)(valves only); V.ornata (Orbigny, 1842). Knudsen:Anomalodesmatafrom theSurinamshelf 123 As canbe seenfrom thelist, thefirst threespecies recordedbyAltena(1971b)were not foundinthe presentmaterial.Of these,Anticorbulasinuosais anoligohaline species, byssallyattachedin theboreholesofteredinids.Theremaining twospecies were foundin smallnumbers only (1-5 valves). TheAnomalodesmataoftheCaribbeanregion are poorlyknownbothas regards taxonomy and distribution, and most species havebeenrecorded afew times only. Inthe present contributionI have attempted to summarizeall availablerecords of the species dealtwith.Ihave adheredtotheclassificationproposed by Bernard(1979). The material, including the types, is kept in the NationalMuseum of Natural History, Leiden, the Netherlands.Allshellmeasurements areinmm. Abbreviationsused:v=detachedvalves, p=paired valves(usually live collectedspecimens). THE ENVIRONMENT The physiography and hydrography of the Surinam waters have beentreated by numerous authors. The present review is based on Altena (1969), Cadee (1975), and Vervoort(1967,1971). Theshelfis gently sloping downto a depthofabout 100m. Theshelfedge is located about80nauticalmilesoffthecoast.Overlarge areas theshelfis completely flat.Anum- berof slopes, formerterraces, occur. A calcareousshoulderis presentat the continental slope. Theshelfreaches its greatestdepth(95-100 m), some distancebeforethecalcareous shoulder.Thereis a very distinctsubmarinethrough running thefulllengthof theconti- nentalslope. Thecalcareousshoulderrises fromthistrough, reaching its greatestheight atabout93m,falling offsteeplyintothe deep sea. Near thecoast,the bottomsedimentis predominantly mud. Withincreasing depth moreor less coarsesanddominates,oftenmixedwithlarge amounts of calcareousskele- talremains.Thetroughalong thecalcareousshoulderis filledwithmud.Thesedimentof theslope is dominatedby soft mud. Thehydrography is dominatedby thewestwarddirectedcurrent carrying very tur- bidwater originating fromtheAmazonRiver.This causes aheavy deposition ofmud in thenearshorewaters toa depthof20-25 m. Becauseof theinteractionofthetidalmove- mentandthewestern current,themud shoalsarealways onthemove.Upwelling occurs commonly and is the main cause of the relatively high nutrientcontent of the water. Outsideof theturbidcoastalwater,a zoneofrelativelyhigh primary production occurs, located at depths ofbetween20 and 60 m. The temperatureof the bottomwater varies between23°Cand28°C at 100m depth attheshelfedge. Theupwelling is nowaccompa- niedby apronounced loweringofthewater temperature.Thesalinityatthebottomvaries between34and 36.5%o. 124 BASTERIA,Vol. 69, No. 4-6, 2005 SYSTEMATICS Poromyidae Poromya rostrata Rehder, 1943(figs2, 11-13) Poromyagranulata(pars); Dall,1881:108;1886: 281. PoromyarostrataRehder,1943:189,pi. 19figs 11,12;Parker, 1960:323,pi.5fig.20a,b; Rice&Kornicker, 1965:137,pi. 16figs9, 10. Material. - 'Snellius' SurinamShelf Expedition,March-May 1966,OCPSI, stations:Al/19v,B2/12v, C3/3v, D4/9v, F6/llv, A9/53v, A10/31v, All/3v, A12/lv, A15/15v, A25/20v, A26/34v,A27/33v, A29/9v, D33/4v,F6/lp, F38/5v, F39/2v, F40/25v, F41/29v,F42/5v, F44/13v+ lp, F45/lv, F47/lv,G56/3v, G57/llv, H57/2p; 'Luymes'SurinamShelf Expedition, March-April 1969, OCPS II, stations:L90/lv,I93/lv, K104/4v, JllO/lv,J112/14v+2p,1114/6v,I116/45v+2p,I117/28v,I118/29v+lp; 'Luymes'GuyanaShelf Expedition,August-September1970, CICAR cruise 15,stations:2/2v, 4/2v, 5/19v,6/18v, 15/lv,16/2v, 17/9v,26/4v,31/8v, 39/9v,40/7v,43/lv, 50/9v,52/9v,56/lv, 57/6v,59/4v,62/5v, 63/lv,64/3v,65/3v,68/2v,70/8v. Additional material. - U.S.CoastSurveySteamer'Blake':Barbados,183m,NMNH/1valve;Sta.262, l.iii.1879,12°01'45"N61°47'25"W,172m,fine sand,NMNH/1specimen(dry), 1valve. U.S. Commission ofFish & Fisheries, 'Albatross': Sta. 2404, 15.iii.1885,28°44'N 85°16'W(Gulfof Mexico), 110m,grey sand,NMNH/9valves;Sta.2602,18.X.1885,34°38'30"N75°33'30"W (CapeHatteras to Charleston S.C.), 227 m, rock, sand, NMNH/11 valves; Sta. 2646, 9.iv.l886, 25°47'N 80°05'W (off Florida),155m, greysand, foraminifera,NMNH/7valves. 'Eolis' cruises 1910-15 (DrJ.B.Henderson): SandKeys, Florida,115m,NMNH/1specimen(dry). State University ofIowaExpeditiontoBarbados,1918(DrJ.B. Henderson):19stationsoffBarbados at depthsof46-186m, altogetherNMNH/3specimens(dry) and 64valves;Sta.115,offAntigua,220m, NMNH/25valves. OffDelray Beach,Palm Beach County,Florida,128m,NMNH/1specimen(dry), holotypeUSNM No. 536152. (6) R.H. Parkerleg. 1960:MississippiDelta region,82-88m,ZMUC/3valves. Shell.- Thevalveis solid, inequilateral, thepostumbonal part forming 53-57%of the total length. Itisinequivalve, the rightvalvebeing thelarger.Inlateralviewtheumbois prominent andpointed, andthepostero-dorsal edge is only slightly curved.Theposteri- or part of the valve is rostrate, this character being more prominent in the left valve. Smallervalves are lessrostrate,some being regularly oval inoutline.The wholeexternal surface is densely coveredwithregular, radiating rows of fine granules. Theright valve has astrong cardinaltooth, theleftvalvehasa distinctposterior lateraltooth.The right valvehas adistinct regular crenulationalong theventraledge; theleftvalveis devoidof crenulation.Thewholeinteriorsurfacehasafineradiating striation.Theposterior partof thepallial impression is straight or slightly concave. Knudsen:Anomalodesmatafromthe Surinamshelf 125 Fig. 2.Records ofPoromyarostrataRehder,1943. indicates”live” specimens; indicatesemptyshells. Softparts. - The gross anatomyis similar to thatofP. granulata Nyst& Westendorp, 1839,studiedbyYonge (1928) andMorton(1981). Thesiphonal tentacles(seven pairs and one unpaired dorsally) are slenderand pointed, but stoutand bluntin P. granulata. The inhalantsiphon hasa large interiorvalve, having apointed ventraledge. Themantleis very delicate, thickened along theventral edge. The conchiolinat the mantleedge has minutespines withflatbases and topsandstraight or slightlyconcave sides.Theseptum is delicatewithsmall septal musclesand two pairs ofbranchialsieves. Thefootiselon- gate,andtheanterior labialpalps are very large. Measurements.- Theholotype is7.3mmlong,thelargest valveofthepresent collec- tion measures 10.5mm. Remarks.- Thespecies was identifiedby comparison withtheholotype. Themateri- alofPoromya fromtheCaribbeanregionkept intheNMNHwasexamined.Thecollection consistsof some50samples, nearly onehalfof whichwas assigned to P. granulata while theremaining oneswerenotassigned tospecies.Anumberofsamplesproved tobe P.rostrata;they arelistedunder'Additionalmaterial';among thesewerefoursamples assigned toP. granulata andrecorded by Dall(1881,1886). Poromya granulata is thetype of thegenus. Itwas describedfromthePliocene (?) of Belgium. ItsrecenthorizontaldistributionextendsfromWestGreenlandtoMoroccoand MadeiraandincludestheMediterranean;the reported verticalrangeisfrom30to 2650m. Therecords ofthespecies fromtheCaribbeanregion by Dall(1881,1886)havebeenquot- ed by subsequent authors, e.g. Johnson (1934) and Abbott (1974). The samples from NMNH seenby meappear tobelongto several species and donot includeany material ofP. granulata, indicating thatthisspecies doesnotoccur in theCaribbeanregion. In Poromya granulata the shape of the valve is oval, with a straight posterior end, whereasin P.rostrata thepostero-dorsal edge isstraight andtheposterior endisrostrate. 126 BASTERIA,Vol. 69, No.4-6, 2005 InP.granulata versusP. rostrata theumboisroundedinsteadof pointed, theventral edge of theright valveis smooth, not crenulated,andthepallial sinusis shallow,not(nearly) absent. Distribution.- Previousrecords ofP.rostrata appearin thelistofadditionalmaterial. The horizontaldistributionextendsfromabout34°38'N tooffFrench Guyana to52°50'W. Thereis asinglerecord fromtheGulfofMexico.Theverticaldistributionisfrom33 to227 m (live specimens 33-172 m). Cuspidariidae Cuspidaria luymesi spec. nov. (figs3,4) Material.- HolotypeRMNH101065(indicatedby asteriskinfollowingenumerationofmaterial),all otherspecimensareparatypes:RMNH 101066-101077 'Snellius' Surinam Shelf Expedition, March-May 1966, OCPS I, stations: B2/lv, A9/lv*, AlO/lv, All/lv,F41/lv,H57/lv; 'Luymes'SurinamExpedition,March-April 1969, OCPSII,stations: M73/lv,J112/lv; 'Luymes'GuyanaShelfExpedition,August-September1970,CICAR cruise 15,stations:5/2v, 39/lv, 56/2v,57/2v,63/lv,64/lv. Diagnosis. - Commarginal sculpture becoming more distinct towardsthe edge and theposterior projection; left valvewith a distinct sulcus along the postero-dorsal edge; right valvewith a long posterior lateral tooth; interiorof shell glossy with a radiating sculpture. Shell.- Theshellis delicate,semi-transparent, slightly inequivalve and inequilateral, thepostumbonal partforming61-63%ofthetotallength.Theumboisroundedandslight- lyprosogyrate.Theposterior projectionis moderately long andonly indistinctly marked; itsposterior edgeis truncate. Theumbonalpartof theantero-dorsaledge maybeslightly thickenedor reflected, particularly inthe larger left valves.The posterior dorsaledge is slightly concave. Theleftvalvehasa distinctsulcus along andparalleltothepostero-dorsal edge; thesulcus gradually becomesless distincttowardsthe posteriorend. Thepos- tero-ventraledge is only slightly concave. The umbonalpart of the external surface is smooth, but gradually an irregular, close-set commarginal sculpture develops which gradually becomes coarser towards theedge. At the posterior projection this sculpture turns upwards along alinerunning fromneartheumboto thepostero-ventral angle; the line sometimes formsa slight sulcus. Dorsal ofthe lineof curvature thedirectionof the sculpture reflects theshape oftheposterior edge. Itbecomes coarser, more close-set and wrinkledbeing formedbytheperiostracum. Thetwo specimens withsoftpartshavepart oftheshellcoveredwithacoatingconsistingofmudwithembeddedsand grains,forami- niferaand bryozoa. Thecoating may attain athickness of0.7mm; in theholotype itis presentontheventralpartoftheposterior projection and intheparatypeontheanterior partof theshell.Thecoating isabsentin thesingle ('dead') valves.Thehinge is delicate; Knudsen:AnomalodesmatafromtheSurinamshelf 127 Fig.3.Cuspidarialuymesi,holotype.a,exterior ofright valve;b, interior ofrightvalve;c,hingeand umbo ofright valve(RMNH 101066). theresiliferis triangular, projecting postero-ventrally. Therightvalvehas adistinct, elon- gateposterior lateraltooth, extending fromalittlebehindtheresilifer, fading offposteri- orly to some distanceanteriorof the adductor scar. Thissculpture appears as rows of opaquespots ontheumbonalpartoftheshellexterior. Softparts.- Themantleisdelicatewithanextremely thickenededge, thepedal open- ing extends nearly halfthedistance tothe base ofthesiphon. The siphonal sheathisthin withathickenedpapillose edge. Theinhalantsiphon isstoutwithareddishbrowndistal half,theexhalantsiphon is small.Thesiphonal tentaclesarestoutwithextended,moreor less disc-shaped distalends. Theseptumis very muscularwithfourpairsof septalpores. About20evenly distributedand delicatelateralseptal muscles arepresent. Theanterior septal retractors aretripartite;the mediansection isfreeashortdistancebehindtheinser- tion.Thefootisratherlarge, pointed. Measurementsandproportions. - holotype paratype length 12.9mm 15.9mm height 7.3 mm 9.7mm breadth 2.6mm 4.1mm postumbonallengthheight/length 0.57 0.61 postumbonallengthbreadth/length 0.20 0.25 128 BASTERIA, Vol. 69,No. 4-6,2005 Fig.4.Records ofCuspidarialuymesi spec.nov.and C. altenaispec. nov. Remarks. - The present species is established with some hesitation.It seems to be closetotheNorthAtlanticCuspidaria obesa(Loven,1846).Ihavecompared thenewspecies withspecimens o] C.obesa.Thelatterhasashorterposteriorprojection, alessdistinct corn- marginal sculpture, ashort,butmore projectinglateraltoothanda straight postero-dorsaledge. Italsolacks theradiating sculpture oftheinterior.Cuspidaria luymesi wouldalso seem to be close tc C. pellucida (Stimpson, 1853), a species knownfrom the northwest Atlantic, fromthe GulfofSt. Lawrence to Maine,and depths ofbetween 75 and 175 m. Verrill& Bush(1898:805,pi. 75fig.8, pi. 76fig.8) describedandfigured thespecies.Itdif- fers from C. luymesi by having a slightly differentoutlineof the shell, whichis nearly smooth; theright valvehas a short, very prominent and strongly curved lateraltooth located immediately posterior of the resilium; it also lacks theradiating striation of the internal surface. Cuspidaria luymesi is also similar in general shape to C. parapodema Bernard (1969:2232,fig.2); the species was also describedandfigured byBernard(1974: 41, fig.2, pi. 12 figs 1,2).Itoccurs in theCalifornianregion atdepths from53to 320m. It hasasimilarshape asC. luymesi, buttheposterior ventraledge is slightly more concave. Ithas a smoothexternal surface, whichlike that of C. luymesi, is partly coated; ithas a shorterlateralhinge toothandlacks theradiating sculptureoftheinternalsurface. Etymology. - This new species is named after the Dutch hydrographic vessel H.NL.M.S. 'Luymes'; J.L.H. Luymes was Chief of the Hydrographic Department of the navy in theyears 1914-1934. Cuspidaria altenai spec. nov. (figs 4, 14,15) Material.- 'Luymes'SurinamShelfExpedition,March-April 1969,OCPSII,Sta.K100,5valves (holo- Knudsen:AnomalodesmatafromtheSurinamshelf 129 typeRMNH 101078 and 4paratypesRMNH 101079). Diagnosis. - Shellthick, inflated.Antero-dorsaledge ofright valve thickened,erect. Rightvalvewithalarge, curved, postero-lateral tooth.Posterioradductorscar triangular, deeplyimpressed. Shell.- Thevalve is solid, inflated, witha short, compressed and dorsally directed posterior projection. Itis strongly inequilateral, theposterior projectionforming 66-70% of thetotal length. The umbois low and theventraledge is strongly curved.Thesculp- ture consists of an irregular, commarginal striation. The antero-dorsaledge of theright valveis thickened and erect, thatof theleft valve is simple. The postero-dorsal edge is straight onthe proximalpart, distallyitis dorsallycurved.Afinedistinctridgeruns from theumbotothepostero-ventralangle oftheposterior projection; dorsalofthistheperios- tracum formsirregular foldsreflecting theshapeof theposterior edge. Oneor two much finerridges run fromtheumboontotheposterior projection, closetothe postero-dorsal edge. Theresilium is triangular, deeply impressed. Theright valve hasavery largeand curved posterior lateral tooth, reaching fromjust posterior of theresilium to thecentral partoftheposterioradductorscar; thelatteris triangularand deeply impressed, particu- larlyattheanterior edge. Measurements and proportions: 1(holotype) 2 3 4 length 10.6mm 12.4mm 10.6mm 10.6mm height 7.7mm 9.4mm 7.6 mm 7.6 mm breadth 2.6mm 3.5mm 2.9mm 2.9mm postumbonallength 6.6 mm 7.6 mm 6.7mm 6.8 mm postumbonal% 62 61 63 64 height/length 0.73 0.76 0.72 0.72 breadth/length 0.25 0.28 0.27 0.27 Remarks.- Thepresentspecies seems tobeclosely relatedtothespecies (erroneous- ly) assigned toCuspidaria subtorta(G.O. Sars, 1878)by Verrill& Bush(1898:806,pi.73 fig. 1,pi. 74 figs 4,5). Thespecies figuredby Verrill& Bush differsfromC.altenaiby having a long posterior lateraltooth in theright valveand asmall prominent toothin the left valve, posterior of theresilifer.Thepresentspecies is alsosimilartoC. pellucida Verrill& Bush(1898: 805,pi.75fig.8, pi.76fig.8).Thelatterhasamoreprominentumboandadif- ferently shaped ventraledge. Thehinge teethofthetwo species are similarbothhaving a prominenttooth intheposterior rightvalve.Thelargest valves studiedby Verrill&Bush measuredless than5 mmlength,andmaybejuveniles. Thepresent valvesmayrepresent theadultsof C.pellucida. Etymology. - Thenewspecies is namedin honourof DrC.O. van Regteren Altena, 130 BASTERIA,Vol. 69, No.4-6, 2005 Fig.5.Records ofCardiomyaornatissima (Orbigny, 1842). curator of molluscs in the Rijksmuseum van Natuurlijke Historie, Leiden, 1952-1968. Cardiomyaornatissima (Orbigny, 1842)(fig.5) Cardiomyaornatissima;Knudsen, 1982:133. Material. - 'Snellius' Surinam Shelf Expedition,March-May 1966,OCPSI,stations: Al/5v,B2/10v, C3/5v,D4/5v,F6/10v,A9/17v,A10/9v,A15/2v,A25/5v,A26/18v,A27/13v, D30/lv,D31/lv, D32/lv,F38/2v, F40/27v,F41/15v,F42/5v,F43/lv,F44/7v,F45/3v,G56/2v; 'Luymes'Surinam Expedition,March-April 1969, OCPSII,stations: I70/lv,M85/2v,L87/lv,I93/lv, K104/lv,K106/2v,JllO/lv,I116/12v,I117/12v,I118/8v; 'Luymes'Guyana Shelf Expedition,August-September1970,CICAR cruise 15,stations: 4/lv, 5/6v, 6/1lv + lp, 16/2v, 17/6v,39/6v, 40/2v,41/lv,42/lv, 63/3v + lp, 64/14v,65/2v,68/lv,69/lv, 70/2v,71/llv, 113/5v+lp. Remarks.- Knudsen(1982) identifiedhismaterial by comparison with the syntypes. Thesculpture ofthe valves is very characteristic, consisting ofvery prominent radiating ribs. The leftvalvehas 13-14ribs whiletheright valvehas only 7-8. In theleftvalvethe posteriormost rib is bipartite, whilethe corresponding one in theright valve is undivid- ed. Distribution.- Knudsen (1982) summarizedthe known distribution:from theCape Hatterasregion (about35°N) tothenortheasterncoastofBrazil atdepths from4(?), 24 (?), 34to 620m.