JournalofVertebratePaleontology23(2):404±419,June2003 q2003bytheSocietyofVertebratePaleontology THELATECRETACEOUSPLACENTAL MAMMALKULBECKIA J.DAVIDARCHIBALD1andALEXANDERO.AVERIANOV2 1DepartmentofBiology,SanDiegoStateUniversity,SanDiego,California92182-4614,U.S.A.; [email protected]; 2ZoologicalInstitute,RussianAcademyofSciences,Universitetskayanab.,SaintPetersburg199034,Russia ABSTRACTÐKulbeckia,a placental mammal fromthelateTuronian±Coniacian (LateCretaceous)ofUzbekistan, wasoriginallyplacedinthemonotypicKulbeckiidae.ImportantnewmaterialindicatesthatKulbeckiaisthebasalmost memberof ``Zalambdalestidae’’, which also includes Zalambdalestes, Barunlestes, and the poorly known Alymlestes, allfromtheLateCretaceousofAsia.Kulbeckiashareswithotherzalambdalestids:anarrow,somewhatelongated snout;procumbent,enlarged,andopen-rootedmediallowerincisorwithenamelrestrictedtothemoreventrolabial surface;andanteroposteriorlycompressedandcentrallypinchedmolartrigonids.Commensuratewithits10-million- yearearlieragerelativetootherzalambdalestids,itisnotableinitssmallersize,probableretentionoffourlower incisors,bifurcatedortwo-rootedlowercanine,relativelysmallerorabsentdiastematabetweenanteriorteeth,more linguallyplacedcristidobliqua,lessreducedM3andm3,andmoredorsalandposteriorplacementoftheangular processinadults.Kulbeckiakansaica(Tadjikistan)andKulbeckiarara(Uzbekistan)areregardedassynonymsof Kulbeckiakulbecke,theonlyrecognizedspeciesofKulbeckia. INTRODUCTION Methods WeusethedentalterminologyofNessovetal. Herewedescribeanddiscussmaterialalmostexclusively (1998:®g.1)withtwoadditions.Wede®netheareabounded fromtheBissektyFormation(UpperCretaceous,upperTuron- bythepreparaconularandpostparaconularcristae,andthelin- ian±Coniacian),Dzharakuduk,Uzbekistan,withonespecimen gualmarginoftheparaconeastheparaconularbasin.Wede®ne fromtheYalovachFormation(UpperCretaceous,lowerSan- theareaboundedbythepremetaconularandpostmetaconular tonian),Kansai,Tadjikistanthatwereferto``Zalambdalesti- cristae,andlingualmarginofthemetaconeasthemetaconular dae’’. We compare these fossils with previously described taxa basin.Measurementsweretakenaccordingtothemethodillus- ofCretaceouseutherians. tratedbyArchibald(1982:®g.1).Atleastthreemethodsof Thepaleoecology,geology,andbiostratigraphyoftheBis- namingeutherianpremolarshavebeenproposed.Inorderto sektyFormation(includingitscorrelationwiththeYalovach maintainthetraditionalidenti®cationofpremolars1through4 Formation)wasdescribedindetailinNessovetal.(1998)and ineutherians,Clemens(1973)suggestedthatthepremolaroc- Archibaldetal.(1998).Hereweonlyprovideabriefsummary casionallyfoundinthethirdpositioninGypsonictopsspp.be andpresentnewinformation.The2001mescarpmentat called``c.''Whilemaintainingthetraditional1through4pre- DzharakudukinthecentralKyzylkumDesert,Uzbekistancon- molarcount,usingthethirdletterofthealphabethasthead- sists(frombottomtotop)oftheUchkuduk(brackishandma- vantageofrecognizingthatthistoothisinthethirdposition. rine),Dzheirantuj(marine),Kenyktjube(marginalmarine),Bis- Morerecently,Cifelli(2000)suggestedthatthistoothshould sekty(¯uvial),andAitym(marginalmarine)formations.The bedesignatedbyan``x.''Unfortunately,thisoffersnosugges- BissektyFormationhasproducedarichvertebratefaunaof tionastothepositionofthistoothandthuswefeelthatof about100species(Nessov,1997).Localitiesintheoverlying thesetwoschemes,theoneproposedbyClemens(1973)is AitymFormationproducedextensivemarineinvertebrates.In preferable.Inrecentyearsithasbecomeclearthatatotalof 1999,ChrisKingandNoelMorrisdiscoveredfossilsofmarine ®vepremolarsisverycommoninavarietyofCretaceouseu- invertebratesatthebaseofthesectioninwhatwasinterpreted therians,andthatthethirdpremolarhasbeenrepeatedlylost. astheUchkudukFormation.Theinvertebrateandmarinefau- Thus,whileitrequiressomerelearningofnomenclaturewefeel nasarestillunderstudy(King,Morris,andWard,pers.comm., thatitsisbesttorefertothepremolarsas1,2,3,4,and5 1999),butonepreliminaryassessmentsuggeststheBissekty whenthereissuf®cientreasontoactuallynamethepremolar Formationisofpost-Cenomanianageandmaybepartofa sites.Thus,forthepurposesofthispaper,whenfourpremolars thicklowerTuroniansuccession(i.e.,itislowerormiddleTu- arepresent,theyareidenti®edasupperorlower1,2,4,and ronian).Alternatively,itisyoungerthanatleastsomelower 5,basedoninformationthatposition3islostinearlyeutherians Turonianunits,butolderthantheearliestSantonian(i.e.,itis (Novacek,1986;Archibald,1996;ArchibaldandAverianov, Coniacian).Whicheverhypothesisiscorrect,theBissektyfauna 1997,1998;Nessovetal.,1998).Premolars4and5correspond willbeamongthemosttightlycorrelatedLateCretaceousfau- tonumbers3and4inmostothertraditionaldescriptions.Teeth nasintheworldbecauseofthepresenceofgoodmarinefaunas wereprojectedonacomputerscreenusingavideocamera belowandaboveinthesamesection.Fornow,wetreatthe mountedonabinocularmicroscopeandmeasuredtothenearest BissektyfaunaasupperTuronianthroughConiacianinage,the 0.1mmusingNIHImage1.61software.Unlessotherwisein- sameassessmentoriginallysuggestedbyNessov(seeNessov dicated,the®guresandphotographsarebytheauthors.Pho- etal.,1998).Thelowestlocality,CDZH-17a,isconsideredto tographsweretakenwithaNikonCoolPix990digitalcamera. beupperTuronianinageandtheothersareconsideredtobe Abbreviations Institutional:BMNH,BritishMuseumof Coniacian,althoughthereisnoclearbasisforplacingtheTu- NaturalHistory;CCMGE,Chernyshev'sCentralMuseumof ronian/Coniacianboundary.Thesesitesareabout10million GeologicalExploration,SaintPetersburg;IZANUz,Instituteof yearsolderthanthebetter-knownvertebratefaunasoftheGobi ZoologyAcademyNaukUzbekistan,Tashkent;MAE,Mon- Desert(Kielan-Jaworowskaetal.,2000). golianAcademyofSciencesÐAmericanMuseumofNatural 404 ARCHIBALDANDAVERIANOVÐREVISIONOFKULBECKIA 405 HistoryExpeditions;PSS,PaleontologicalandStratigraphy Distribution Late Cretaceous, Uzbekistan (late Turonian section(GeologicalInstitute),MongolianAcademyofSciences, and Coniacian) and Tadjikistan (Santonian). UlanBaatar;URBAC,Uzbekian/Russian/British/American/Ca- Revised Diagnosis Same as for type and only species. nadianjointpaleontologicalexpedition,KyzylkumDesert,Uz- bekistan, specimens in various institutions in Uzbekistan, Rus- KULBECKIA KULBECKE Nessov, 1993 sia, Great Britain, the U. S,A., and Canada; ZIN C., Systematic Collections, Zoological Institute, Russian Academy of Sciences, Aspanlestes aptap: Nessov, 1985: pl. 2, ®g. 10 (part) SaintPetersburg;ZPALMgM,InstituteofPaleobiology,Polish ?Zalambdalestes sp.: Nessov, 1987: pl. 1, ®g. 9 AcademyofSciences,Warsaw,Mongolianmammals.Locali- Kulbeckia? sp.: Nessov, 1993: pl. 3, ®g. 2 ties:CBI,centralKyzylkum,Bissekty;CDZH,centralKyzylk- Kulbeckia kulbecke: Nessov, 1993: pl. 3, ®gs. 3±4; pl. 4, ®gs. um,Dzharakuduk;FKA,Fergana,Kansai.Anatomical:L,left; 3±5; 1997: pl. 49, ®gs. 1, 2, 6 R,right. ?Kulbeckia kulbecke: Nessov, 1993: pl. 4, ®g. 6; 1997: pl. 49, ®g. 9 SYSTEMATICPALEONTOLOGY Kulbeckia kansaica: Nessov, 1993: pl. 4, ®g. 7; 1997: pl. 49, ®g. 10 MAMMALIALinneaus,1758 Kulbeckia rara: Nessov, 1993: pl. 4, ®g. 8; 1997: pl. 49, ®g. EUTHERIAGill,1872 13 PLACENTALIAOwen,1837sensuRougieretal.,1998 ?Kulbeckia sp.: Nessov, 1993: pl. 4, ®g. 9; 1997: pl. 49, ®g. 5 GLIRIFORMESWyssandMeng,1996 Gen. indet.: Nessov et al., 1994: pl. 7, ®gs. 5, 9 ``ZALAMBDALESTIDAE''GregoryandSimpson,1926 ?Aspanlestes sp.: Nessov, 1997: pl. 49, ®g. 4 Kulbeckiidae:Nessov,1993,1997. Holotype CCMGE 52/12455, isolated left M1 (not M2?, De®nition ThetaxaZalambdalestes,Barunlestes,Kulbeck- Nessov, 1993). ia,andAlymlestesandtheirmostrecentcommonancestor. Type Locality Locality CBI-5a, upper part of Bissekty For- IncludedTaxa ZalambdalestesGregoryandSimpson, mation, Upper Cretaceous (Coniacian), Dzharakuduk, western 1926;BarunlestesKielan-Jaworowska,1975;KulbeckiaNes- Uzbekistan. sov,1993;AlymlestesAverianovandNessov,1995. Referred Specimens Upper dentition: URBAC 99-53, L Comments Werefer``Zalambdalestidae''toGliriformesof side of skull from near end of snout to middle of orbit with P1, WyssandMeng(1996)baseduponthephylogeneticanalysis P4, P5, M1 and partial M2 and roots for three incisors, C, P2, ofArchibaldetal.(2001).Gliriformesincludesthe(crowntax- and M3; ZIN C.82566, R double-rooted C lacking roots; UR- on)Glires(DuplicidentataandSimplicidentata)andstemtaxa BAC 98-102, a chemically etched R P5; CCMGE 6/12455, R thatshareamorerecentcommonancestorwithGliresthanthey M1; URBAC 98-100, R M1; URBAC 98-104, R M1 missing dowithotherPlacentalia(sensuRougieretal.,1998).Archi- parastylar lobe and protocone; URBAC 98-105, L M1 missing baldetal.(2001)didnotrecoveramonophyleticZalambda- lingual half; URBAC 98-134, R M1 missing paracone; CCMGE lestidaeintheiranalysis,ratherBarunlesteswasfoundtobe 9/12455, R M2 missing parastylar lobe (holotype of Kulbeckia thenearestsistergrouptoGlires.Thus,formally``Zalambda- kansaica Nessov, 1993); URBAC 98-101, L M1 or 2 missing lestidae''isplacedinquotessuchashasbeendonefor``Zhe- stylar shelf and paracone; URBAC 98-103, L M2, worn, miss- lestidae''(e.g.,Archibald,1996)toindicatenonmonophylyof ing parastylar lobe; CCMGE 5/12176, L M2 missing parastylar thetaxon.Thisusageisfollowedwhenformallyreferringto lobe (holotype of Kulbeckia rara Nessov, 1993, not M1); ZIN thistaxonwithinthecontextasarguedbyArchibaldetal. C.82565, L M2; URBAC 97-1, R M2 missing parastylar lobe; (2001). CCMGE 54/12455, R M3; URBAC 98-135; R M3 with some McKennaandBell(1997)includedZalambdalestes,Alym- damage to lingual and posterolabial surfaces. Possibly CCMGE lestes,andBarunlestesinZalambdalestidae.Weagreethat 73/12455, L M1? (Nessov, 1993:pl. 3, ®g. 6; 1997:pl.