Recognition of the marine gastropod Caecum tumidum Carpenter, 1858 (Caenogastropoda, Truncatelloidea) in the Pliocene of the North Sea Basin

2015·3.8 MB·English

by  Hoeksema, Dick F

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Recognition of the marine gastropod
Caecum tumidum Carpenter, 1858
(Caenogastropoda, Truncatelloidea)
in the Pliocene of the North Sea Basin
Dick F. Hoeksema
Watertoren28,NL-4336KCMiddelburg,TheNetherlands;[email protected]
Jonathan A. Todd
DepartmentofEarthSciences,NaturalHistoryMuseum,CromwellRoad,
LondonSW75BD,UnitedKingdom;[email protected]
tativesoftheCaecinae. 105
In1858Carpenterdescribedthefossil“Caecumtra- InhiscatalogueofshellsfromtheCrag,Wood
chea”sensuWood(1842,1848)fromthePliocene (1842:459)listedaspecimenof“Caecumtrachea?”
BritishCragMolluscaasnewtoscienceandnamedit foundintheCorallineCrag(Pliocene;Sutton,Suffolk,
Caecumtumidum.Alectotypeisselectedtostabilize UK).Thequestion-markindicatesthatWoodatthat
thespecies.C.tumidumappearsalsopresentinthe timehaddoubtsaboutthisidentificationthatheex-
PlioceneofBelgiumandTheNetherlands.AsC.tu- pressedasfollows,“TherecentBritishshellisregu-
midumuntilrecentlyhasbeenmistakenforCaecum larlyannulatedandsmooth,theannuliinmysingle
trachea(Montagu,1803)=Caecumimperforatum(Kan- cragspecimenaremoreirregularandrugose.”
macher,1798)aswellasforCaecummammillatum InhisMonographoftheCragMollusca,Wood
Wood,1848,diagnosticcharactersandphotographs (1848:115-116)omittedthequestion-mark,evidently
arepresentedtodistinguishthethreespecies. consideringhisspeciestobeconspecificwiththeRe-
centCaecumtrachea(Montagu,1803).
Keywords:Gastropoda,Caenogastropoda,Truncatelloidea, TenyearslaterCarpenter(1858:426-427),“having
Caecidae,Caecinae,Caecum,Pliocene,NorthSeaBasin,Belgium, subjectedallthespecimensintheBritishMuseum,as
TheNetherlands,UnitedKingdom. wellassomesentmebyMr.Wood,toaveryrigidex-
aminationunderthemicroscope”,recognizedandde-
scribed“C.trachea”sensuWoodasnewtoscience,
Introduction namingitCaecumtumidum.
Jeffreys(1867:76),discussingC.trachea,wrote,“I
ThefamilyCaecidaeconsistsofagroupofinterstitial donotconsideritaBritishfossil;forIbelievethe
benthicgastropods,inwhichtheshell,afterthelarval shellsdescribedandfiguredbySearlesWoodfrom
stagewhichisregularlycoiled,isformedbyalong, theCorallineCragarenotthisspecies,buthisC.mam-
slightlycurvedtube.Duringthegrowth,earlystages millatum.”Jeffreysdidnotrefertothedescriptionby
maybeeitherpreserved(subfamiliesStrebloceratinae Carpenter.
andPedumicrinae)ordiscardedandtheposteriorend Wood(1872:87)didnotrespondtoJeffreys.He
sealedbyaseptum(subfamilyCaecinae)(Pizziniet positivelyrespondedtoCarpenterbyinsertinginhis
al.,2013:1).Inthispaperweonlydealwithrepresen- SupplementtotheMonographoftheCragMolluscaa
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surveyof“theCragCaecidaeaccordingtoCarpenter’s Material and methods
views(thoughIdonotfullyagreewithhim)”,together
withafootnoteinwhichWoodremindedreadersofhis Diagnosticcharacters.–Nofronietal.(1997:5)sum-
“noteofinterrogationagainstC.trachea”inhiscata- marizedfourvalidlydiagnosticcharactersthatmay
logue(Wood,1842:459;seeabove).Despitethisfoot- distinguishCaecumspecies:1.shellsize,2.shapeof
note,twoyearslaterin1874,Woodlisted“C.trachea”in septum,3.presence/absenceandtypeof
theSynopticalList(page209)andIndex(page224)of (micro-)sculptureand4.presence/absenceofan
hisSupplement,merelymentioning“C.tumidum aperturalvarix.Theyadd,“Itisstressedthatthemor-
Carp.”inthecolumnof‘Remarks’(page209). phologicalcharactershereemployed(especiallythe
Harmer(1923:848)repeatedJeffreys’opinionon septumandthemicrosculpture)arevalidlydiagnostic
thefossil“C.trachea”,butfollowedWood:“Jeffreys whenobservedinfull-grown,wellpreservedspeci-
consideredthattheCorallineCragfossildescribedby mens;therangeofvariabilityofmanycharactersin
Woodunderthepresentnamecouldnotbeidentified someinstance,forcestoanalyseasmanycharactersas
withtherecentC.tracheaofMontagu,inwhichthe possibleineachcase,andaslargesamplesaspossible
concentricribsaremoredistinctandcloselyarranged, toavoidmisinterpretations.”Forexamplethemi-
preferringtoregarditasavarietyofWood’sC.mam- crosculptureshouldnotbehandledastheonlydiag-
millatum.Onthewhole,however,…IadoptWood’s nosticfeature,“Oftenspeciesthatareusuallystriate,
view,whichistheonemostgenerallyaccepted.” presentspecimenswithveryweak(orevennearlyab-
HarmerdidnotevenmentionCarpenter’sdescription sent)microsculpture(andviceversa).”
ofC.tumidum. Terminology.–BasedonFretter&Graham(1978:
Since1874thetaxonCaecumtumidumCarpenter, 234),Lightfoot(1992:172-173)andNofronietal.(1997:
1858seemstohavebeenforgotten.Unjustly,aswe 4-5):apicalend–thesmaller,narrower,closedupper
willshow. endofthetube;septum–closureoftheshellafterthe
InpreparationforPartIIoftheatlasDefossiele previousstageisdiscarded;mucro–appendageoften
schelpenvandeNederlandsekustHoeksema&Raad visibleontheseptum;aperture–theroundopeningat
(2015)studiedthefamilyCaecidae.Thankstothesup- thelowerendofthetube;aperturalend–thelower
portofthemembersoftheWerkgroepGeologieofthe endofthetube;varix–transversethickeningorring
106 KoninklijkZeeuwschGenootschapderWetenschap- precedingtheedgeoftheaperture,whichalwayssig-
pen(Middelburg,TheNetherlands)adozensamples nifiesanadultshellandtheendofgrowth;dorsalside
offossilCaecumspecimenscollectedfromthebeaches –convexsideofthetube(dorsalaspectofseptumis
oftheWesterschelde,provinceofZeeland,The “twelveo’clock”);ventralside–concavesideofthe
Netherlands,weremadeavailableforstudy.Thesam- tube;ribs–longitudinal,raisedsculpture(equivalent
plescontainundisputedspecimensofCaecumglabrum tothespiralsculptureofthenormallycoiledgas-
(Montagu,1803)andC.mammillatumWood,1848. tropods);rings–transverse,raisedsculpture(equiva-
ShellsofathirdCaecumspeciesatfirstsightresem- lenttotheaxialsculptureofthenormallycoiled
bledC.trachea,butacloserexaminationshowedcon- gastropods);microsculpture–sculpturevisibleathigh
sistentdifferences.Consequentlythefirstauthor magnification.
studiedthefossilCaecumshellsintheRoyalBelgian Systematics.–Thecurrentsystematicsisbasedon
InstituteforNaturalSciences(Brussels,Belgium)and theWorldRegisterofMarineSpecies(Bouchet&
thosefromDutchboreholesdepositedintheNaturalis Gofas,2015),consultedinJuly2015.
BiodiversityCenter(Leiden,TheNetherlands).TheC. Abbreviationsandacronyms.–AR:coll.A.C.
trachea-likespeciesispresentinbothmuseums,all (Riaan)Rijken,Middelburg,TheNetherlands;DH:
specimenswereobtainedfromPliocenedeposits, coll.D.F.(Dick)Hoeksema,Middelburg,TheNether-
whichindicatesthatthebeach-collectedspecimens lands;coll.:collection;fig(s):figure(s);Fig(s):figure(s)
alsocanbeconsideredtobeofPlioceneorigin.Study- inthepresentpaper;FN:coll.F.A.D.(Freddy)van
ingthepublicationsontheBritishPlioceneCragMol- Nieulande,Nieuw-enSt.Joosland,TheNetherlands;
luscamentionedabove,Carpenter’sdescriptionofC. frm(s):fragment(s);GS:coll.G.F.(George)Simons,
tumidumappearedstrikinglyapplicabletothisspecies. Middelburg,TheNetherlands;HJ:coll.H.A.A.(Bart)
Thesecondauthortrackeddownthespecimensof“C. deJong,Middelburg,TheNetherlands;HR:coll.H.J.
trachea”sensuWoodintheNaturalHistoryMuseum (Harry)Raad,Kruiningen,TheNetherlands;LK:coll.
(London,UK),thesyntypesonwhichCarpenter(1858: L.(Lex)Kattenwinkel,Goes,TheNetherlands;
426-427)hadbasedhisdescriptionofC.tumidum,and, NHMUK:NaturalHistoryMuseum(formerlyBritish
asexpected,theyprovedtobeconspecificwiththe MuseumofNaturalHistory),London,UnitedKing-
mentionedfossilC.trachea-likespecimensfromBel- dom;NMR:NatuurhistorischMuseumRotterdam,
giumandTheNetherlands. Rotterdam,TheNetherlands;pl(s):plate(s);PM:coll.
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P.W.(Peter)Moerdijk,Middelburg,TheNetherlands; Pouwer,2013:9-10,fig.1),1spmexcoll.AR,
RBINS:RoyalBelgianInstituteforNaturalSciences, RGM.1008223(Fig.7a);2spms,1frmLK;Borssele,
Brussels,Belgium;RGM:FossilMolluscacoll.Natu- DeKaloot(provinceofZeeland,TheNetherlands),
ralisBiodiversityCenter(formerlyRijksmuseumvan beach,2spms(Figs4-6),2frmsFN;4spms,5frms
GeologieenMineralogie),Leiden,TheNetherlands; HJ;2spms,1frmHR;1frmPM;Nieuwvliet,Zwarte
spm(s):specimen(s);WoRMS:WorldRegisterofMa- Polder(provinceofZeeland,TheNetherlands),
rineSpecies(Bouchet&Gofas,2015). beach,1frmHR;Domburg(provinceofZeeland,The
Typematerial.–IntheNaturalHistoryMuseum Netherlands),beach,1spm,RGM,excoll.J.vanDal-
(London,UK),notypespecimensselectedbyCarpen- sum(infortunatelylost).
terhimselfcouldbefound.Theonlysampleof“C. Specimenslabeledas“C.imperforatum”inRGM
trachea”fromtheCorallineCragFormationislot fromPliocenedepositsinboreholesinTheNether-
NHMUKPIG2066,donatedtothemuseumbyWood landsallappearedtobelongtoC.tumidum(April
(Fig.1).Thewholelotcomprises19specimensad- 2015).
heredtoathinblackpaperstripgluedontoathicker InadditiontothespecimensofC.tumidumthe
whitepieceofcard.Originallyatleastanotherfour firstauthorstudiedforcomparisonasampleof
specimenswerepresent,butatsometimethesehave beachedspecimensoffreshdeadC.trachea(excoll.
beenremovedandthepresentwhereaboutsofthese G.J.Geuze,DH;Figs11-14)fromMartinhal,S.Portu-
shellsareunknown.Onthecardonecanreadin gal,andsamplesofC.mammillatumwashedashoreat
Wood’shandwritinginpencil“Cor.Crag/Caecum thebeachesofBaarland(seeabove;AR,LK;Figs15-
trachea?/Sutton”;acrossandgreenstickerindicate 17),Borssele/DeKaloot(FN,HJ,HR),Ritthem(GS),
thespecimenthathasbeenfigured(Wood,1848:pl. Vlissingen(HR),Nieuwvliet/ZwartePolder(HJ)and
20fig.5),whichisconfirmedbyacrossonthemu- DeBanjaard(HJ),provinceofZeeland,TheNether-
seumlabel(Fig.2).AsCarpenter(1858:427)basedhis lands.
descriptionofC.tumidumon“allthespecimensinthe
BritishMuseum,aswellassomesentmebyMr. Systematics
Wood”andasall19specimensseemconspecific,lot
NHMUKPIG2066canbeconsideredatypeseriesof ClassGastropodaCuvier,1795
syntypes.Thespecimenwhichhasbeenfigured SubclassCaenogastropodaCox,1960 107
(Wood,1848:pl.20fig.5)andtowhichCarpenter OrderLittorinimorphaGolikov&Starobogatov,1975
(1858:427)referredinhisoriginaldescription,ishere SuperfamilyTruncatelloideaGray,1840
selectedaslectotypeandrenumberedNHMUKPI FamilyCaecidaeGray,1850
G2066(1)(Fig.3),makingtheother18specimens SubfamilyCaecinaeGray,1850
paralectotypes.Thelectotypeis2.79mmlongand
amongthelargestofthe19typespecimens. CaecumFleming,1813
Othermaterialexamined.–BergenopZoom
(provinceofNoord-Brabant,TheNetherlands),bore- CaecumtumidumCarpenter,1858(Figs3-10)
hole2,RvD9283,90-91mbelowsurface,Oosterhout
Formation–mollusczoneMolD1,Pliocene(Piacenz- Caecumtrachea?-Wood,1842:459(question-markbyWood).
ian),1spm,RGM.937740;Dongen(provinceof NotC.tracheaMontagu,1803.
Noord-Brabant,TheNetherlands),borehole Caecumtrachea–Wood,1848:115-116,pl.20fig.5;1872:87;
B44G.0043,175-176mbelowsurface,OosterhoutFor- 1874:209,224.Harmer,1923:847-848,pl.64fig.32.Trausel
mation–mollusczoneMolD1,Pliocene(Piacenzian), &Slieker,2015:NMR26235.NotC.tracheaMontagu,1803.
1spm,RGM.937737.a(Figs7b,8-10);Kallo(province Caecum(Anellum)tumidum–Carpenter,1858:426-427.
ofOost-Vlaanderen,Belgium),Verrebroekdok,Lillo Caecummammillatum–Jeffreys,1867:76.Marquet,1997:18,28-
Formation,OorderenMember,Atrinalevel,Pliocene 29fig.3;1998:70fig.
(Piacenzian),1spm,RBINSno.IRScNBIST5897 Caecumimperforatum-VanRegterenAltena,Bloklander&Poud-
(Marquet,1997:18,28-29;Marquet,1998:70fig.;asC. eroyen,1955:29,pl.6fig.58;1965:17,pl.6fig.58.
mammillatum);Kallo,Deurganckdok,LilloFormation,
LuchtbalorOorderenMember,Pliocene(LateZan- Originaldescription.–Caecum(Anellum)tumidum
cleantoPiacenzian),4spms,LK;Baarland(province Carpenter,1858.
ofZeeland,TheNetherlands),beachnearCamping Testatereti,sublaeviseuannulisobsoletisornata;aper-
Scheldeoord,insanddredgedfromtheWester- turahaudcontracta,annulotumidocincta;septomamil-
scheldeatthe‘OverloopvanHansweert’and/orthe lato,plusminusvetumente;marginelateraliconvexo,
‘DrempelvanHansweert’intheWesterscheldeestu- dorsumversussubangulato;operculum?-.
ary,derivedfromPliocenedeposits(Moerdijk& Long.0.11,lat.0.018-0.024.
Hoeksema, D.F. & Todd, J.A.–CaecumtumiduminthePlioceneoftheNorthSeaBasin
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Figs1-10.Caecumtumidum,Carpenter,1858.1,typeseriesfromtheCorallineCragFormation,Pliocene(Zanclean),Sutton,Suffolk,UK,
NHMUKPIG2066;2,museumlabelofNHMUK,withacrossindicatingthatthecrossonthecardofthetypeseriesindentifiesthefig-
uredspecimen;3,lectotype,length2.79mm,NHMUKPIG2066(1)=thespmpicturedbyWood(1848:pl20fig5);4-6,2spms,length2.7
and2.9mm,washedashoreatBorssele,DeKaloot,FN;4,scale500micrometer;5,aperturalendFig4a,showingavarix,scale100mi-
crometer;6,detaillowerparttubeFig4a,showingmicroscopicpitting,scale50micrometer;7-10,2spms;7,scale500micrometer;7a,1
spm,length2.5mm,Baarlandbeach,provinceofZeeland,TheNetherlands,Pliocene,excoll.AR,RGM.1008223;7b,1spm,length2.8
mm,Dongen(provinceofNoord-Brabant,TheNetherlands),boreholeB44G.0043,175-176mbelowsurface,OosterhoutFormation–
mollusczoneMolD1,Pliocene(Piacenzian),RGM.937737.a;8,aperturalendFig7b,scale100micrometer;9,apicalend,scale100mi-
crometer;10,detaillowerparttubeFig7b,showingmicroscopicpitting,scale50micrometer.
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Hab.Sutton,Cor.Crag.Mus.Brit.&c. oftenshowsathickeningoranelevatedsmoothring
=C.trachea,SearlesWood,Crag.Moll.p.115,pl.20,f. precedingtheedgeoftheaperture(Figs4-5,7-8;com-
5(?pars),nonMont.etauct. pareVanRegterenAltenaetal.,1955&1965:pl.6fig.
[Shellslender,round,almostsmoothorobsoletely 58,asC.imperforatum).Dimensionsofthelongest
annulated;aperturenotconstricted,withswollen specimenmeasured(Fig.4b):length2.93mm,diame-
ring;septummamillate,moreorlessswollen;lateral ter0.49mm(apicalend)-0.62mm(aperture);meas-
sides(i.e.hacspeciedorsali(Carpenter,1858:420)=ob- uredlikeL,dandDinfig.2ofPortaetal.(1993:3).
servedfromthedorsalside)convex,dorsalsidein- Locustypicus.–Sutton,Suffolk,UnitedKingdom
clinedtobeingsomewhatangular;operculum Stratumtypicum.–RamsholtorSudbourneMem-
unknown.Length2.79mm,diameter0.46-0.61mm]. ber,CorallineCragFormation,Pliocene(LateZan-
Remarks:Carpenter’smeasurementsareininches, clean).
1.0inch=25.4mm.AccordingtoSclater(1893:440), Distribution.–C.tumidumiswidelydistributedin
pages413-432ofCarpenter’spaperwerepublishedin thePlioceneoftheNorthSeaBasin,geographically
1858,andpages433-448in1859.AsC.tumidumwas fromUnitedKingdom(Sutton,Suffolk)toBelgium
describedonpages426-427,theyearofpublicationof (provinceofOost-Vlaanderen)andTheNetherlands
thisspeciesis1858. (provincesofZeelandandNoord-Brabant)andstrati-
Diagnosis.–AfossilCaecumwithanentirelyor graphicallyfromLateZanclean(CorallineCragFor-
partiallytransverselyrugosetube;theseptumele- mation,UnitedKingdomandpossiblyLuchtbal
vated,hemispherical,obliquelytruncatedwithakeel Member,Belgium)toPiacenzian(OorderenMember,
andtheaperturalendoftenwithavarix.Sometimes BelgiumandOosterhoutFormation–mollusczone
microscopicpits,largestbetweentherugae.Length: MolD1,TheNetherlands).
2.9mm.
Reviseddescription.–Theadultshellisaminute, Discussion
brittle,regularlycurvedtube.Thesurfaceoftheshell
usuallybears,entirelyorpartially,irregular,rugose, InthestudyofC.tumidumthreeothertaxaplayan
ring-shaped,transversethickenings(Figs3-10).The importantrole,viz.C.imperforatum(Kanmacher,
tubeandseptumshowanirregularpatternofmicro- 1798),C.trachea(Montagu,1803)andC.mammillatum
scopicpits,largestbetweentherugae(Marquet,1997: Wood,1848.AccordingtoWoRMS(consultedinJuly 109
18,28-29fig.3,1998:70fig.;Figs5-6,8-10).Theapical 2015)C.imperforatumhastobeconsideredadubious
endissealedbyanelevated,moreorlesshemispheri- synonymofC.trachea.
calseptum,oftensomewhatobliquelytruncatedat Caecumtrachea(Figs11-14)occursfromthe
theventralsideandcylindricalwithakeelatthedor- Mioceneuntilthepresentdayandisstillacon-
salside(thekeelisusuallypositionedat12o’clockto stituentoftheRecentEuropeanandNWAfrican
3o’clock,sometimesalsoweaklypresentaroundthe fauna.Thetubeisentirelyorpartiallycoveredwith
restoftheseptum;Figs4,7,9).Theaperturalend rings,theapicalendwithasomewhatsunkenseptum
C.tumidum C.trachea C.mammillatum
Figs3-10 Figs11-14 Figs15-17
entirelyorpartiallywithtrans-
entirely,sometimespartially, entirelysmoothorwithsomefainttrans-
macrosculpturetube verselyrugose,ring-shaped
coveredwithrings versering-shapedthickenings
thickenings
microsculpturetube irregularpits oftenlongitudinalstriae oftenlongitudinalstriae
elevated,hemispherical, somewhatsunk,witharounded sunk,withanarrowpapilliform
septum
obliquelytruncated,withakeel mucro roundedmucro
sometimeswithathickeningoranele-
oftenwithathickeningoranele- sometimeswithathickening
vatedsmoothringprecedingtheedgeof
aperturalend vatedsmoothringprecedingthe precedingtheedgeoftheaper-
theaperture,and/oranarrowengraved
edgeoftheaperture ture
ringatsomedistancefromtheaperture
maximumlength 2.9mm 3.8mm 3.4mm
Table1.C.tumidumshowsconsistentdifferencesfromC.tracheaandC.mammillatum.
Hoeksema, D.F. & Todd, J.A.–CaecumtumiduminthePlioceneoftheNorthSeaBasin
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Figs11-14.Caecumtrachea(Montagu,1803),1spm,length2.8mm,Martinhalbeach,Algarve,S.Portugal,Recent,excoll.G.J.Geuze,DH;
11,scale500micrometer;12,aperturalend,scale100micrometer;13,apicalend,scale100micrometer;14,detailtube,showingmicro-
scopiclongitudinalstriae,scale50micrometer.
withaprotruding,eccentric(12-1o’clock),rounded fromPliocenedepositsintheNorthSeaBasin.The
mucro,theaperturalendsometimeswithathickening tubehasasmoothsurface,sometimeswithsomefaint
precedingtheedgeoftheaperture.Oftenami- rings,theapicalendwithasunkenseptumwithanar-
crosculptureoflongitudinalstriae.Length:3.8mm. row,(oftenvery)protruding,eccentric(12-1o’clock),
(VanAartsen,1977:15figs22-23,17;Chirli,2006:66- papilliform,roundedmucro,theaperturalendsome-
68,pl.28figs7-10;Chirli&Linse,2011:89,pl.26fig. timeswithathickeningoranelevatedsmoothring
3a;Fretter&Graham,1978:233-234;Jeffreys,1867:75- precedingtheedgeoftheaperture,and/oranarrow
77;Landauetal.,2004:pl.14fig.1,61-62;VanderLin- engravedringatsomedistancefromtheaperture
den&Moolenbeek,2000:89-91figs27-28;Panetta, (compareVanRegterenAltenaetal.,1955&1965:pl.6
1980:288-289,294-295figs4-6;Portaetal.,1993:2-5 fig.56).Oftenamicrosculptureoflongitudinalstriae.
figs1-9). Length:3.4mm.(Wood,1848:116,pl.20fig.4;
Caecummammillatum(Figs15-17)isafossilCaecum Harmer,1923:847,pl.64fig.31;VanRegterenAltena
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Figs15-17.CaecummammillatumWood,1848,1spm,length3.4mm,showingmicroscopiclongitudinalstriae,Baarlandbeach,province 111
ofZeeland,TheNetherlands,Pliocene,excoll.AR,RGM.1008222;15,scale500micrometer;16,aperturalend,showingavarix,scale100
micrometer;17,apicalend,scale100micrometer.
etal.,1955:29,1965:17,pl.6fig.56;Hoeksema& C.trachea.Mostlikelyalsofig.9ofHoeksema&Raad
Raad,2015:28fig.10).Theseptumlookssomewhat (2015:28;asC.trachea)canbereferredtosuchaspeci-
likethatoftheRecentCaecumvitreumCarpenter,1859 menofC.mammillatum(herefiguredinFig.18).So
(Nofronietal.,1997:9fig.16). Wood’sfig.5amayrepresentC.tracheaorperhaps
ThemicrosculptureonthetubeofaCaecumshell, C.mammillatum,butnotC.tumidum.
ifpresent,isusuallyonlyvisibleonwellpreserved StudyingsurveysoftheEuropeanandNorth
specimens.ItcanbeobservedonC.tumidum,C.tra- AfricanCaecidae,neitherthepresentdayfauna(Van
cheaandC.mammillatumusingobliquelightingatmi- Aartsen,1977;Panetta,1980;Nofronietal.,1997;Van
croscopemagnificationsgreaterthanrespectively derLinden&Moolenbeek,2000)norotherfossilfau-
40x,40xand10x. nas(Portaetal.,1993;Landauetal.,2004;Chirli,2006;
ConsideringthespecimensofC.tumidumnow Chirli&Linse,2011)containaCaecumspeciesmatch-
presentinthetypeseries,thedescriptionof“C.tra- ingC.tumidum.Theseptumofthepresentspecies,
chea”sensuWood(1848:115-116,pl.20fig.5)isnot moreorlesshemisphericalwithakeel,mostclosely
accurateinallrespects.Theobservations“length1/8 resemblesthatofCaecumarmoricumDeFolin,1869,
ofaninch”(=about3.18mm)and“theclosedtermi- butthetubeofthatRecentspeciesissmooth,witha
nationpreciselyresemblingtherecentspeciesin delicatelongitudinalmicrosculptureandwithoutan
beingobliquelytruncatedandobtuselypointed”are aperturalvarix(Hoeksema&Segers,1993:81,82figs
notcorrect.Thefigs5(withlongitudinalstriae,clear- 1A-E2A-D,85,87fig.7A-B).Theirregular,rugose,
estvisiblebetweentherings)and5a(aseptumwith ring-liketransversethickeningsarereminiscentof
roundedmucro)arereminiscentofC.trachea.In CaecumgougerotiMoroni&Ruggiere,1985,butthe
Carpenter’s(1858:427;1859:435)opiniontheseptum transversethickeningsonthesurfaceofthisMiocene-
offig.5aprobablyfitswithintherangeofvariationof Pliocenespeciesaremainlyconcentratedontheapi-
C.mammillatum,someformslikefig.5aapproaching calendofthetubeandtheseptumofC.gougeroti
Hoeksema, D.F. & Todd, J.A.–CaecumtumiduminthePlioceneoftheNorthSeaBasin
B2015-15:Basteria-2015 11/20/2015 3:12 PM Page 112
den,TheNetherlands)andAuke-FlorianHiemstrafor
makingFigs4-17.WethankTomMeijerandRonald
Pouwerforinformationonthepalaeontologicalageof
theRGMsamples.PeterMoerdijkisacknowledgedfor
hissuggestionstoimprovethetranslationoftheorigi-
naldescription.FinallywethankArieJanssenand
BernardLandauforcriticallyreviewingthemanu-
script.
References
Fig18.Caecumcf.mam-
millatumWood,1848.1 Aartsen,J.J.VAN,1977.RevisionoftheEastAtlanticand
wornspm,showingaC. MediterraneanCaecidae.—Basteria41(1-4):7-19.
trachea-likeseptum, Bouchet,P.&Gofas,S.,editors,2015.WorldRegisterofMarine
length2.7mm,Domburg Species(WoRMS),Mollusca.–www.marinespecies.orgon
beach,provinceofZee- 2015-07-31.
land,TheNetherlands, Bruyne,R.H.de,Leeuwen,S.J.van,GmeligMeyling,A.W.&
Pliocene,excoll.M. Daan,R.,(red.),2013.SchelpdierenvanhetNederlandseNo-
Donze,RGM.794216. ordzeegebied.Ecologischeatlasvandemarieneweekdieren
(Mollusca).UitgeverijTirion,UtrechtenStichtingAnemoon,
Lisse.
showsatriangular,roundedmucro(Chirli,2006:63- Carpenter,P.P.,1858-1859.FirstStepstowardsaMonographof
64,pl.27figs5-8). theCaecidae,aFamilyofRostriferousGasteropoda.–Pro-
Caecumtumidumseems,likeC.mammillatum,tobe ceedingsoftheZoologicalSocietyofLondon26:413-432
restrictedtothePlioceneoftheNorthSeaBasin,the (1858),433-444(1859).
latterbeingthecommonestspeciespresent.C.glabrum Chirli,C.,2006.MalacofaunaPliocenicaToscana,Vol.5
isrelativelyrareinthePlioceneoftheNorthBasin CaenogastropodaCox,1959Part1:1-144,pls1-46.Firenze.
112 (Wood,1848:117;Marquet,1997:18-19,1998:71),but Chirli,C.&Linse,U.,2011.ThePleistoceneMarineGastropods
remainsaconstituentoftheNEAtlanticandNorth ofRhodesIsland(Greece):1-447.Firenze.
Seafauna(Fretter&Graham,1978:234-235;De Fretter,V.&Graham,A.,1978.TheProsobranchMolluscsof
Bruyneetal.,2013:205).AfourthPlioceneCaecum- BritainandDenmarkPart4MarineRissoacea.–TheJournal
speciesfromtheNorthSeaBasin,CaecumliratumCar- ofMolluscanStudies,Supplement6:153-241.
penter,1858,isonlyknownfromtheCorallineCrag Harmer,F.W.,1923.ThePlioceneMolluscaofGreatBritain
FormationofSuttonbytheholotypeintheNatural beingsupplementarytoS.V.Wood’sMonographoftheCrag
HistoryMuseum(London,UK)andwhichrequires Mollusca,Vol.2,Part3.-MonographofthePalaeontograph-
re-study(Carpenter,1858:421).Incontradictiontothe icalSocietyLondon75(352):705-856,pls57-64..
distributiongivenbyChirli(2006:67-68)andChirli& Hoeksema,D.F.&Raad,H.J.,2015.Defossieleschelpenvande
Linse(2011:89),weconcludethatthepresenceoffos- NederlandsekustII,deel10.Hydrobiidae,Cochliopidae,
silC.tracheaintheNorthSeaBasinstilllacksconvinc- Iravadiidae,TruncatellidaeenCaecidae.–Spirula402:24-29.
ingevidence. Hoeksema,D.F.&Segers,W.,1993.Onthesystematicsanddis-
tributionofthemarinegastropodCaecumarmoricumDe
Acknowledgements Folin,1869(Prosobranchia,Caecidae).–GloriaMaris31(6):
79-88.
WearegratefultoGerardGeuze,BartdeJong,Lex Jeffreys,G.W.,1867.BritishConchology,oranaccountofthe
Kattenwinkel,PeterMoerdijk,FreddyvanNieulande, MolluscawhichnowinhabittheBritishIslesandthesur-
HarryRaad,RiaanRijkenandGeorgeSimons(Werk- roundingseas.Vol.4:1-486,pls1-8.VanVoorst,London.
groepGeologie,KoninklijkZeeuwschGenootschap Landau,B.,Marquet,R.&Grigis,M.,2004.TheEarlyPliocene
derWetenschappen,Middelburg,TheNetherlands) Gastropoda(Mollusca)ofEstepona,SouthernSpain.Part2:
fortheloanordonationofmaterialandallowingusto Orthogastropoda,Neotaenioglossa.–Palaeontos4:1-108.
publishtheirrecords.WethankAnneliseFolieand Lightfoot,J.,1992.CaecidaeoftheWesternAtlantic.Part1.–Of
RobertMarquetformakingavailabletheCaecumma- SeaandShore14(4):171-185.
terialintheRoyalBelgianInstituteforNaturalSci- Linden,J.vander&Moolenbeek,R.G.,2000.Caecidae(Mol-
ences(Brussels,Belgium).WethankFrankWesselingh lusca:Gastropoda)fromMauritania.–VitaMarina47(3):81-
andRonaldPouwerforallowingustostudytheCae- 92.
cumsamplesintheNaturalisBiodiversityCenter(Lei- Marquet,R.,1997.PliocenegastropodfaunasfromKallo(Oost-
Basteria79(4-6),2015
B2015-15:Basteria-2015 11/20/2015 3:12 PM Page 113
Vlaanderen,Belgium).Part2.Caenogastropoda:Potamidi- 1955.DefossieleschelpenvandeNederlandsestrandenen
daetoTornidae.–ContributionstoTertiaryandQuaternary zeegaten,2.–Basteria19(2-3):27-34,pls5-8.
Geology34(1-2):9-29. RegterenAltena,C.O.van,Bloklander,A.&Pouderoyen,L.P.,
Marquet,R.,1998.DepliocenegastropodenfaunavanKallo 1965.DefossieleschelpenvandeNederlandsestrandenen
(Oost-Vlaanderen,België):1-246.Publicatieno.17,Belgis- zeegaten.Eersteserie,tweededruk:1-55,pls1-22.Neder-
cheVerenigingvoorPaleontologie,Antwerpen. landseMalacologischeVereniging,Leiden.
Moerdijk,P.W.&Pouwer,R.,2013.Laevastartequiespacisnov. Sclater,W.L.,1893.ListoftheDatesofDeliveryoftheSheetsof
spec.(Mollusca,Bivalvia,Astartidae)fromthePlioceneof the‘Proceedings’oftheZoologicalSocietyofLondon,from
TheNetherlands.–CainozoicResearch10(1-2):9-13. thecommencementin1830to1859.–ProceedingsoftheZo-
Nofroni,I.,Pizzini,M.&Oliverio,M.,1997.Contributiontothe ologicalSocietyofLondon61:435-440.
knowledgeofthefamilyCaecidae.3.RevisionoftheCaeci- Trausel,J.&Slieker,F.,2015.NMR26235.-www.nmr-pics.nl>
daeoftheCanaryIslands(Caenogastropoda:Rissooidea).– Caecidae>PLEISTOCENECaecumtrachea(Montagu,
Argonauta10(7-12):3-32. 1803)on2015-07-31.
Panetta,P.,1980.LafamigliaCaecidaenelMediterraneo.–Bol- Wood,S.V.,1842.ACatalogueofShellsfromtheCrag.–The
lettinoMalacologico16(7-8):277-300. AnnalsandMagazineofNaturalHistory9:455-462,pl.5.
Pizzini,M.,Raines,B&Vannozzi,A.,2013.ThefamilyCaecidae Wood,S.V.,1848.AMonographoftheCragMollusca:Vol.1
intheSouth-WestPacific(Gastropoda:Rissooidea).–Bollet- Univalves-MonographofthePalaeontographicalSociety
tinoMalacologico49,Suppl.10:1-78. London1(1):i-xii,1-208,pls1-21.
Porta,J.de,Martinell,J.&GonzálezDelgado,J.A.,1993.Caeci- Wood,S.V.,1872.SupplementtotheCragMollusca,Vol.3Uni-
dae(Gastropoda,Mesogastropoda)delNeógenoyCuater- valvesandBivalves,Part1–MonographofthePalaeonto-
narioMarinosdelMediterráneoNoroccidentalydela graphicalSocietyLondon25(113):i-xxxi,1-99,pls1-7.
PenínsulaIbérica.–RevistaEspañoladePaleontología8(1): Wood,S.V.,1874.SupplementtotheCragMollusca,Vol.3Uni-
1-13. valvesandBivalves,Part2-MonographofthePalaeonto-
RegterenAltena,C.O.van,Bloklander,A.&Pouderoyen,L.P., graphicalSocietyLondon27(123):100-231,pls8-11+add.pl.
113
Hoeksema, D.F. & Todd, J.A.–CaecumtumiduminthePlioceneoftheNorthSeaBasin