A new Orbitestella (Gastropoda: Heterobranchia: Orbitestellidae) from Tierra del Fuego, Argentina

2004·3 MB·

THENAUTILUS118(4):160-166,2004 Page160
A new Orbitestella (Gastropoda: Heterobranchia:
Orbitestellidae) from Tierra del Fuego, Argentina
LuizR.L.Simone DiegoG.Zelaya
MuseudeZoologiadaUniversidade DivisionofInvertebrateZoology
deSaoPaulo MuseodeLaPlata
CaixaPostal42594 1900LaPlata,BuenosAires
04299-970SaoPaulo ARGENTINA
BRAZIL [email protected]]
[email protected]
ABSTRACT andMicrodisculacharopa (Tate, 1899)] suggestedthat
Agnaoce,tnweerAsrwpgueesscnpeitedecisinfeaois.srocTtfhhhaOeerrabgcmiettoneerersprtiheizlceoldlaaobliglysyodcaaeotwsfiicodtrnehi.lebyeOjdruabmwfibstrieoslimstiecTtlaihlteeaerdrpmaaasthdieaenlgllocFnwhuiiaectr-ah- beaOrurnbtndi-tahWesesamtrpeirelsilnpmihidte(air1ev9ee8s8hf)HoreuetplseldhrawocnabeotrdtearnbOcrehbfiiactmaoei,nslstyrieedlVlleaairltdeveadadetaitisdonaretti.hhseesPonoVooianrdldtevehaar-n-
lowspire, ornamentedwithnumerous, regularlydistributed, toidea.
spiralthreadsandweaksinuouscommargina]growthlines.The In die present paper a new species ofOrbitestella
entiresurfaceoftheprotoconchiscoveredwithcrispspiral fromtheMagellanicRegionisdescribedonthebasisof
threads.Examinationoftheanatomyrevealedthepresenceof shellmorphologyandgeneralanatomy.
arelativelysmallstomachandtheposteriorregionofgenital
cshyasrtaecmterbsu.lgingintohaemocoelspaceas maindistinguishing MATERIALSANDMETHODS
The studied specimens were collected at die Beagle
INTRODUCTION Channel,TierradelFuego,Argentina(Figure1). Sam-
plesweretakenwithadragnet, fixedin 10%buffered
The Orbitestellidaeareextremelyminute, discoid,and formalinandtransportedtothelaboratorywheremol-
widely umbilicated gastropods, living mainly in the luskswere sortedfrom sediments usingastereoscopic
Southern Hemisphere (Ponder, 1967, 1990; Powell, microscope,andpreservedin70%ethanol.Shell,radula,
1979). The genus Orbitestella Iredale, 1917has avir- jaws, andoperculum morphologywere studiedandil-
tually worldwide distribution, although most of the lustrated using scanning electron microscopy (SEM).
knownspeciesoccurinAustraliaandNewZealand(Pon- For anatomical studies specimens were decalcified in
der, 1990; PonderandKeyzer, 1998). InthenorthAt- Railliet-Henry'ssolution.Twospecimenswereprocessed
lantic, two species have been describedby Rolan and for histology. Semi-thin sections (0.3 |jim thick) were
Rubio(1992):O.similisfromCapeVerdeandO.cubana stainedwithMallory'strichrome(Gabe,1968).Addition-
from Cuba. The only species ofdie genus presently ally, 5 specimens were dissected under stereomicro-
knownfromoffSouthAmericais Orbitestellaponderi scope.Itwasnotpossibletostudytherightsideofthese
Linse, 2002, aspeciesdescribedfromthe EastBeagle specimens (i.e. pallial tentacle, penis, and propodial
Channel(TierradelFuego). Linse (2002) identifiedas flap).
O. ponderi specimens from southern Chile previously Voucherspecimensweredepositedinthe Museode
reportedbyPonder(1990)asOrbitestellasp. LaPlata(MLP)andMuseudeZoologiadaUniversidade
Orbitestella has previously been placed in the Tro- deSaoPaulo(MZSP).
choideaorTruncatelloidea,eitherintheOmalogyridae Abbreviationsusedinthefigures:ad,anteriorlobeof
orOrbitestellidae(Iredale,1917;Thiele,1929;Knightet digestivegland;an,anus;ca,capsulegland;ce,cerebral
al., 1960).Ponder(1967),basedonthestructureofthe ganglion;eg,pallialgenitalgland;cm,columellarmus-
animalsandradula,placedOrbitestellaintheRissooidea cle; cs, crystalline style sac; dg, digestive gland; es,
[asRissoacea].Thispointofviewwasfollowedbyseveral esophagus;ey, eye;fs, footsole;ft, foot;h,heart;go,
subsequent authors (Powell, 1979; Ponder, 1983; Mar- hermaphrodite gonad; gp, pedal ganglion; hy. inner
shall, 1988; Hickman and McLean, 1990). Later on, shellorganiclayer(hypostracum);in,intestine;jw,jaw
Ponder(1990)afterhavingstudiedtheanatomyoftwo plate; mb, mantle border; mf, mantle U-shaped fold;
orbitestellidspecies [Orbitestellawareni Ponder, 1990, nig, mantle gland; mo, mouth; od, odontophore; ol,
:
L.R.L.SimoneandD.G.Zelaya,2004 Page161
Shell ultrastructure: Only one well-defined
crossed-lamellarlayer,about25jjunthick(Figure9).Or-
ganiclayer(hy),athirdofperiostracumthickness,made
moreevidentindecalcifiedshell(Figure16).
Head-foot(Figures 11, 16): Colorcream-yellowish,
uniforminpreservedspecimens. Headinlaidintofoot
(Figure 11). Pairofcephalictentacleswelldeveloped.
Eyes relativelylarge, sunkenintointegument medially
betweenbasesofcephalictentacles;lenssolid,volume
abouthalfthatofeyes(Figure 16).Apairoftentacle-
likeflaps(sometimesreferredtoasa"snout")lyingbe-
tween tentacle bases, flanking mouth. Foot somewhat
pFaitgaugroeni1c.anMeawpspsehcoiewsinagndthneetwypfeinldoicanlgistyof(®O).poofnOdrebriites(t*)e.lla smoalsesievnet,irceyllyincdroivcearlewdhbeynlroentrgacctielida,.oCcocluupmyeilnlgarVamwuhsocrlle;
thick. Posteriormucous glandoccupyingposteriorand
periostracum;op,operculum;os,osphradium;pa,pos- middleregionoffoot.
prtierororipoormduliocubomeu;sofptgp,leadnpadrl;osgtplaoat,ned;-pripoge,m,erpneetnreaildosomtrraganactnul;me;sogp,rgg,asnap;loisvtpaerr,-y ulOuppceetnrotc,3u.yl5eulslmloiwgih(stFhliy;gonuvurecerlle7au)ps:pisnuNgbecawehrnotlrrylalsc.,irhcoulranry,,ptahuicni,sptirraanls,-
gland;st,stomach;sv,seminalvesicle;sy,statocyst;te,
cephalictentacle. Pallial Cavity (Figures 16, 17): Expanded by XA
whorl,withthin,simplemantleborder. Gillabsent. U-
SYSTEMATICS shapedlowfold,sometimesdescribedas"ashort,par-
dCGeyescnilugonssattOrireobnmi)taesbtaesltloawiIreGdatallief,f,19191076,(Tbyypeorsipgeicniaels: tpPihialrglamydeciniutlimeadtsemmdaallnoltb,lee"f,oglddl-oalrnisdkael,(lsyceilelonicabateytde,tdrl(aonFcsiapgtauerrdeeno1cn7y,)lmecffit)r.csuilOdaser-.,
thin,relativelysmall,colordarkbrown,surfaceuniform,
Orbitestellapatagonicanewspecies locatedatmiddle-posteriorpartofroofofpallialcavity
(Figures2-18) (Figure9,po).
wDumitaidreaegdglinsynopaiuslrmiablgsir:ltoihwcrateStahhededsll.,ilnoPersrmnoiatannomudcteoennn,tucemhddeiwrwsioictotuhihsd,cw,reirwaseipkgtusslhpiairnrlluaoylowuddsiissrcpteoirarridnebs-,- Vwwwhhhiooosrrrcllless.r.,aSsltDtioogmmemaassactschihv(aeiFnnidggrlugiagronhendtsaadsi1ld1lme,oo,csa1tg6to,efndu1ali7ld)ny:ifdinreslCvteoefhtmlapol(rfpFieiosdgfiuvonriegnscet1lr6aw)aso.lt
covering entire surface. Radulawith wide, pectinated Circulatory and excretory systems (Figure 16)
rachidiantoothwithsharplypointedcusps;lateraltooth Heartsmall,locatedbetweenstomachandrenalorgan,
plate-like,withamaincuspandsparselyserratedouter posteriortopallialcavity.Renalorgantriangularinsection.
margin;marginaltoothslender,sickle-like.Stomachrel- Digestive system: Mouth on a small protuberance,
ativelysmall. betweententacle-likeflaps (Figure 16). Oraltubenar-
Description: Shell(Figures2-6, 8-10): Minute row,laterallyexpanded.Jawplateslarge,rounded,lat-
(maximumdiameter1.1mm),discoid,widelyumbilicat- erally located and flanked by well-developed muscles
ed,thin,translucent,shiny,upto2.75roundedandreg- (Figure 16); with five serrated rows ofsimple curved
ularlyexpandingwhorls;spiredepressed,slightlyraised plates,posteriorlyconcave,oneachsideofinnersurface
(Figures2-5). Coloryellowish-buff. Periostracumthin, (Figure 15). Odontophoresimilartojawsinsize,with
colorless. Protoconchformedby0.75whorl,about200 several small muscles, but no cartilages (Figure 16).
u,mwide;initiallyonlysculpturedwithlowgranulations, Radula 1:1:1:1:1, somewhatlongerthan odontophore.
followedby10-12spiralthreads (Figure6). First0.25 (Figure 12). Rachidian tooth large, trapezoidal,with
whorlweaklymarkedbystraightgrowthdisruption(Fig- peg-like lateral edges and an excavated base; cutting
ure6). Teleoconchofupto2 roundedwhorls, suture edgepectinated,wide,stronglycurvedinwards,bearing
incised.Umbilicusdeep,wide,representingabout32% 11—13slenderandsharplypointedcusps,graduallybe-
ofmaximum shell diameter (Figure 5). Shell surface coming smaller in outward direction; central cusp
withweak, sinuous commarginal growthlines andnu- straight;lateralcuspssomewhatcurved,narrowerthan
merous, regularly distributed and fine spiral threads centralone (Figure 14). Lateralteethplate-likewith
(Figure8),alsovisibleinsideumbilicus(Figure5);first straightbase;cuttingedgewithalargeprimarycusp,4—
whorl ofteleoconchwith about 10 spiralthreads, last 5 smallerandregularlyseparatedcuspsonouterside,
whorlwith35-37. Shellaperturenearlycircular(about and asmallinnerside cusp, onbase ofprimarycusp
240|j,mhighby270u,mwide)withsinuousperistome (Figure 12). Marginalteethsickle-like, slender,grad-
(Figures4,5). uallynarrowingtosharplypointedtip;secondarycusps,
Page162 THENAUTILUS,Vol. 118,No.4
Figures2-9. Orbitcatellupatagonicanewspecies.2.Holotype,MLP6367.3-7.Paratypes,MLP6368.3.Dorsalview.4.Lateral
view.5.Ventralview.6.Detailoftheprotoconch. 7.Operculum.8.Shellsurfacesculpture.9.Shellultrastructure.Scalebars:
Figures2-4=300jjuti;Figures5=500|xm;Figures6-8= 100|xm;Figure9=20u.m.
L.R.L.SimoneandD.G.Zelaya,2004 Page163
Figures10-11. Orbitestellapatagonica.Paratypes,MZSP38708.10.Dorsalviewofaspecimenseenbytransparency.11.Right
viewofaspecimenremovedfromshell.Scalebars=600u.m.
Figures 12-15. Orbitestellapatagonica. SEM micrographsoftheradula(MZSP38708). 12. Rachidian(re),lateral(It)and
marginal(mr)teeth(dislodged). 13.Detailoflateral(It)andmarginal(mr)teeth.14.Detailofrachidianteeth.15.Jaws.Scale
bars=1(j.m.
re164 THENAUTILUS,Vol. 118,No.4
an sg es ce
Figure 16. Orbitestellapatagonica. Semi-diagrammaticlongitudinalsection. Scalebars = 100u.m.AbbreviationsinMaterials
andMethods.
17
Figures17-18. Orbitestellapatagonica. Anatomicaldetails. 17.Leftsideviewofaspecimenwithpallialcavitysectionedand
deflected;18.Transversalsectioninmiddleregionofcommonglandulargenitalduct.Scalebars:Figure17=100u.m;Figure18
=50\x.m.
L.R.L.SimoneandD.G.Zelaya,2004 Page165
absent (Figures 12, 13). Esophagus originating from testellaponderiwasalsocollectedduringthisstudyalong
middle dorsal region ofodontophore, initiallynarrow, theBeagleChannelatUshuaiaBay(«54°50'S,68°W),
wider posteriorly, entering stomach at anterior-ventral GableIsland(54°54.6'S,67°21.4'W)andSanPioCape
region atside ofstyle sac (Figure 16); esophaguswall (55°5.6' S, 66°28.8' W); at Sloggett Bay (55°00' S,
thick and undulated by presence of glands. Salivary 66°20.6' W) andIslade los Estados (54°46' S, 64°22'
glandssmall,ventraltoesophagusandposteriortoodon- W).ThesenewrecordsconfirmthatO. ponderiispar-
tophore.StomachlargeoccupyingaboutVawhorl,some- tiallysympatricwithO.patagonica.
whatflat,onrightsideofvisceralmass(Figures10,16). OrbitestellapatagonicadiffersfromO.ponderiLinse,
Innergastricsurfacecoveredbycuticle.Stylesacsmall, 2002, by having a more depressed shell, with much
locatedinantero-dorsal region ofstomach,bearingan weakeraxialsculpture androunded aperture. Orbites-
ovoidcrystallinestyle. Stomachlumencontinuouswith tellapatagonicadiffersfromtheAntarcticspeciesofMi-
digestivegland. Digestiveglandcomposedbynon-pig- crodiscula Thiele (1912) byhavinga more depressed,
mentedvacuolarcells. Intestineshort(ahalfofesoph- spirallyornamentedshell.Theratiooftheumbilicus/last
aguslength),originatingbetweenstomachandstylesac, whorldiameterinO.patagonicaissimilartothatofM.
directedforward(Figure16).Anuslocatedonposterior vanhoffeni andgreaterthaninM. subcanaliculata. Or-
endofpallialcavity. bitestellapatagonicaalsodiffersfromtheAustralianand
wpvtcsatntdGrMraerioioeowneaalsofgectedlnllifshlptlseecttieaoey.rslalnstbdelehtstpsaClinioiisaesaotlcardsoctlrcpintseeoavaemutg;ctstemceeclomaieydiiarafvoldlsi.omiicnin;utnotaeph,dn.yeOtrman,lmceosear(lPgta:r)gninFaroolpm.aoiodncasilsnwggdncuntuiGdiodlourgairtnaoouepmltgehoalynielefadacidsgy,af1n,rtnl8dedgbi)gabdgvwlv.einueeoeahstldn0orlnGtei.gwgcoydertr5ielcnyinamnaogectwbliwagnivoeneutphdtesndtla,vhourvuelfledririodceaninolnldttmatndu(givparalfibtf(aeallefrteoFrlorfeeodeuilitutgra,y,gonatulesduucderani,iiwsrtrenldnnieiideiotldtsna.aucrooethplanecegtoSa1thgdadrwns0ereit,aet,oamdopeeeefrinvdersmo1drnebnil6ioooanieoodo)s-nsl-w-.rs-ff wpdntidpraoagNreanrreefnnoeeargrtnoaTdduwliceweatkanhhaargoOlsdtaaegdaoc.iyhmreenslaZnoeanodncdSinedcescruccoateOhrNoshaObueleerfihov..taalrbiceaerlihsrnnnllrtptdolaetHssieahfAadouohnsotbamxnawtgrcdapyoAecepdeiogetnlreofOtevnorlllf,rihmedngtaaafebecmucinerrowirktalacsnrs,teaeeiiaprneesfnc,nte)srgttgrbphctisiireaowisemdpcnnrepelhsimeoeoaeflsfSoecrdcalferstoidsuiee(rlpheuherlii.eesgtestononclrrh,mocsNsniloooalteeofeAwuburessrjxmtdnaysukOtaiphdecrrdehinwfuabrhedngaoilnliadAlctfpidmvttcyeenthliho,alaesuataenasrftnrvnhs.geiiprettetilnnoshiynOlctacpwcmgoprgarlrenhelebicuoOodnit(osid.drasethOpegiublper.essnycy,esi.ismgictpcAmphnieoiaiaoBuategllsrrnnneshvslieae--dd-e-)asatl
Centralnervoussystem: Pairoffusedcerebro-pleu- yondthesetwogenera,onlyLurifaxWarenandBouchet
ralganglialocatedposteriortobuccalbulb;pedalganglia (2001)hasalsobeenreportedtothefamilyOrbitestel-
locatedventraltooraltube. Statocystofabouthalfeye lidae(SmriglioandMariottini,2002).Lurifaxisverydif-
volume, immerse anterior to pedal ganglia into pedal ferentfromtheothergenerainhavingtallerspireand
musculature,withasingleandrelativelylarge(similarto multispiralprotoconch.
eyeindiameter)statolith(Figure16). Orbitestellapatagonicashowsthegeneralanatomical
TamsmpyeeepntcseeirmM)e(.anMtsZeP)a,rSriPaaaltlly3:pf8er7so0:Hm8o9lto+hstepye9tpcyeipselm(ieMdlneoLsscaPl(oi6ftMy3,Ls6e7PMr)iaa6rl(3c76s2h8e0)c,1t|9ix95om8n.sipnoefcdii2-- vfTsfieemhsaraecteleulnrrecmaerelassismonwtafisottsmahh.naeactthRohor,aobmdsiiouetccelaspcaltrueepmlvdyloiiiirofdnupfsgsehdlroeyoelsnnodclcgeeyrsyictbirshaeiledsbtobehrydeisgPahhpotnorndowsdpifoesdirreogtumi(oro1efen9d9adt0libh)lfy.ey-
Type Locality: 54°52' S, 68°12' W, Isla H, Beagle Ponder(1990)ascharacteristicforOrbitestella:thepec-
Channel,TierradelFuego,Argentina. tinatedcuttingedgeoftherachidiantoothinO. pata-
Distribution: Knownonlyfromtypelocality. gPoonnidcear,is19w9i0d;ertheancduttniontgaesdgterioanfgtuhlearlaatserianltOe.etwhawreernei
Etymology: ThespeciesnamederivesfromPatagon- described byPonder (1990) as awide plate with nu-
ia,regiononsouthernpartofSouthAmerica. merous small cusps in the outer margin, while in O.
patagonicatheyarenarrowerandhavingonlyfewcusps;
DISCUSSION marginalteetharewideandnumerouslycuspedinthe
species described by Ponder (1990) and are narrow,
ThreespeciesofOrbitestellidaewerepreviouslyreport- hook-likeandwithoutadditionalcuspsinO.patagonica.
edfromtheMagellanicRegionandadjacentsubantarc- ThejawsinO.patagonicahaveonlyfiverowsofserrated
ticwaters: Microdiscula subcanaliculata (Smith, 1875) plates,whilePonder(1990)describedsixandsevenrows
fromSouthGeorgiaIslandsandSouthOrkneysIslands forthespecieshestudied. BothradulaandjawsofO.
(Ponder,1983and1990),MicrodisculauanhoffeniThie- patagonicaaresimilartothoseofO.ponderi.
le,1912,fromSouthShetlandsIslands(Dell,1990)and Orbitestellapatagonica, asitwaspreviouslyreported
Orbitestella ponderi from East Beagle Channel and forO.warenibyPonder(1990),hasthegeneralanatom-
southeastern PacificOcean, Chile (Linse,2002). Orbi- icalfeaturesofabasalheterobranch,suchasthelackof
THENAUTILUS,Vol. 118,No.
ctenidium, the hermaphrodite genital system mostly Ocean.ThesesZoologicaevol.74.A.R.A.Ruggell,Liech-
bulging into the haemocoel, the lack ofodontophoral tenstein,251pp.,21pis.
cartilagesandthepresenceofapigmentedmantlegland. Marshall,B.A.1988.Skeneidae,VitrinellideandOrbitestelli-
dae(Mollusca:Gastropoda)associatedwithbiogenicsub-
strata from bathyal depths offNewZealand and New
ACKNOWLEDGMENTS SouthWales.JournalofNaturalHistory22:949-1004.
Ponder,W. F. 1967. The classificationofthe Rissoidaeand
fTAsMouphurseestccreiaoauumlmtiemmhaneonornlfsotorsaNwbniiesotswenhsotfttZeohelMelaeiilxcmdapranrosndedpuseisTscsceicrteuhisPlepaaitirpnvaaganrtnTahdhoteoniBetg.cfuaofdAlree.lenewtiMcoata,iraCosn.nahdnaIodtlofultaathrflhetoserero PondeOaO(Sr1crri,7tbbg)iiin:Wottynee.1sssI9tts3Feeol,-llfall2niit12dddh,94aae8ee3S+.oRwaouinpytEtidaahsht.lRodOin1eSsris-oskeco1clnrei3lielei.pltydtiyaideIoao,sneflsaR(nNioMdsfoessl,wsoliouwdsZimaceteeaah,:lnaaeCGniawrdnse,gttvauriZxloeoaop.wopolsTodoirfagda)ytnasheo9-e,f
forcommentsonthepaper. Partofthisstudywasde- AntarcticandSub-Antarcticspecies.BritishAntarcticSur-
velopedwiththesupportoffundingtotheseniorauthor vey,ScientificReport108:1-96.
byFundacaodeAmparoaPesquisadoEstadode Sao Ponder,W.F.1990.TheanatomyandrelationshipsoftheOr-
Paulo (Fapesp), Process#00/11074-5 and00/11357-7. bitestellidae (Gastropoda: Heterobranchia). Journal of
cDiilefgoorZSecliaeynaceisaandFeTlelcohwnoofltohgeyN(aCtiOoNnIaClERTe)s,eaArrcghenCtoiunna-. PondetAMro.o,ildWlWeeua.l.slcsFpapn(.aeSdn8std.5u)d4Ri-.Me8os5Gl.l85u6:sdicne5a:P1K.5eT-yL5hz.3eer2B..eSeo1su9lt9eh8ye,.rnGS.uSpyJe.nrtfhBae.msiiRslo.yssFV,aaluavnnada-
LITERATURECITED ofAustralia.Vol.5.CSIROPublishing,Melbourne,part
Bvhi,pp.565-1234.
DHGeailbclek,,tmaoPNahRfaanr.etndMiNu,s.Kfre,s.aauCwul1p1.1n1r9Z9Ha16aS9ei83g.0sao.e.tflpanoapenATtr.nrdnheyditeccaJMh2.rRn7ucco:iHltssa.qises1ucs-ueMi3SMsfcm1eioL1aclho.ae.litfauisBnostLuno.collaslooe1fgwtA9iiinT9qntg0ruh.eeooslcsf.eShpystaeschMcCtieeaaeoaslmuRnsanorottygeinyaafc,lsetErrSrSdeecoionviptccieoeisendueicsrott.e,noy PPRooowlneadlnetpfaO(l,rerhaln,,dbemedE.iiAm)W.tl.CFee.yrasPanW-teerntFgesondrl4hsoola,BwogFau.nabappdtrspI1Rea.trn9Aucrer7.ablh1o9imas8W.pohde8Paeoe.sl-hN,rdl3yease1l2a.n91ow8n9.9agA.2d1neuZ.17dnce9hykTa8i.flHl8wgarea.honMotneadmAedrl,nprapeoMttcCeoshawoonxletlladlrlso.uiioApgnsxtepisIcl.chcn,aaiaa:.neCl—5tlsW0iaMRc.0saoaesfrvipOliFfipitcnise.hetecweaa,P,otnogifL.neSoandnutnLeuphodas-ref
Series35:1-169. Conchiglia23(262):17-20.
Iredale,T. 1917.Moremolluscanname-changes,genericand Smriglio,C.andP.Mariottini.2002.LtirifaxvitreusWarenand
specific.ProceedingsoftheMalacologicalSocietyofLon- Bouchet,2001 (Gastropoda,Orbitestellidae),firstreport
don12:322-330. fromWesternMediterraneanSea.BollettinoMalacologico
KnighYttio,ocnksJ.e.lBsI.on,nTLar.neadRt.iRs.eCoRxoo,nbeArI.tnsvMoe.nrt.eKb1er9na6nt0,e.PLS.aylseRto.enmtaBotalitoctgaeynd,e(sREc..riCLp..- Thiel3eF8i,:sJh.e4r51,-942J97e..naHa1n:d1b-u1c13h4.dersystematischenWeichtierkunde.
Moore,Ed),I(Mollusca1),pp.1169-1310. Waren,A. andP. Bouchet. 2001. GastropodaandMonopla-
Linse,K.2002.TheshelledMagellanicMollusca:withspecial cophorafromhydrothermalventsandseeps:newtaxaand
reference to biogeographic relations in the Southern records.TheVeliger44:116-231.