Eucholoeops Ameghino, 1887 (Xenarthra, Tardigrada, Megalonychidae) from the Santa Cruz Formation, Argentine Patagonia: implications for the systematics of Santacrucian sloths

Geodiversitas

François Pujos¹  Nestor Toledo¹  M. Susana Bargo¹  Sergio F. Vizcaíno¹  Gerardo De Iuliis¹ 

关键词: Xenarthra;    Sloths;    Eucholoeops;    late Early Miocene;    Santa Cruz;    neotype;    new synonyms;    Xenarthra;    Paresseux;    Eucholoeops;    fin du Miocène inférieur;    Santa Cruz;    néotype;    synonymes nouveaux;   

DOI  :  10.5252/g2014n2a2

学科分类：生物科学（综合）

来源: Museum National d Histoire Naturelle

【 摘 要 】

Newwell-preservedremainsofthemegalonychidslothEucholoeopsAmeghino,1887recoveredunderstrictstratigraphiccontrolfromlateEarlyMioceneSantaCruzFormation(c.19to14Ma;SantacrucianAge),togetherwithanalysisofoldercollections,considerationofintraspecificvariationinextinctandextantsloths,andassessmentofthevalidityoftheearlyliteratureonSantacruciansloths,permitrevisionofthestatusofthenumerousspecieserectedforthisgenus.ThecurrentcontributiondealswiththesystematicsofE.ingensAmeghino,1887,butitsmethodologyprovidesabasisforrevisionofotherEucholoeopsspecies,aswellasotherslothgenerarecoveredfromtheSantaCruzFormation.ThefailuretomakeprogressonthesystematicsoftheSantacruciantaxasincetheirfirstdescriptionisshowntobeduemainlytoacombinationofthepoorqualityofmanyofthespecimens,whichareoftenfragmentedandincompleteandfromoldercollections,aswellasinadequatestratigraphicandgeographiccontroloftheirrecovery,anoverlyrigidrelianceontheearlyliteraturethataccompaniedtheirdescriptions,andlackofconsiderationforintraspecificvariation.AneotypeisdesignatedforE.ingens,astheoriginalspecimenisnolongeravailable.ThespeciesE.latirostrisAmeghino,1891,E.externusAmeghino,1891,andE.curtusAmeghino,1894areconsideredasjuniorsynonymsofE.ingens.

【 授权许可】

Unknown