Trocholites Conrad, 1838 (Nautiloidea, Tarphycerida) in the Middle Ordovician of the Prague Basin and its palaeobiogeographical significance

Bulletin of geosciences

Manda Å ¹ 

关键词: Middle Ordovician;    Dobrotivian;    Darriwilian;    Cephalopoda;    Tarphycerida;    taxonomy;    Prague Basin;   

DOI  :  

来源: Czech Geological Survey

【 摘 要 】

NautiloidsoftheorderTarphyceridaareacharacteristiccomponentofwarm-waterOrdovicianfaunasofBalticaandLaurentiabutareusuallyabsentfromthecoolerhighlatitudemarineenvironments.ThepresenceofthetarphyceridTrocholites,reportedfromtheMiddleOrdovician,Dobrotivian(lateDarriwilian)strataoftheIberianChainandArmoricanMassif(peri-GondwananEurope),provideanexception.LituitesprimulusBarrande,1865,representedbyasinglepoorly-preservedindividualwasreportedfromcoevalstratainthePragueBasin(Perunica)anddoubtfullyassignedtoCurtocerasorTrocholites.Newbiostratigraphicalywell-constrainedspecimensofTrocholitesdescribedanddiscussedfromtheearlyDobrotivianofthePragueBasin,areconspecificwithTrocholitesfugaxpreviouslydescribedfromtheIberianChainandArmoricanMassif.ThecontemporaneouspresenceofTrocholitesfugaxinPerunicaandperi-GondwananterranesisadditionalevidenceforfaunalconnectionsbetweenthesemicrocontinentsduringtheDobrotivian.BycomparisonwiththeprecedingLlanvirnian(earlyDarriwilian)fauna,thelowdiversityDobrotiviancephalopodfaunaofthePragueBasinsuggestsanincreasingfaunalseparationbetweenPerunicaandBaltica.TheoccurrenceofTrocholitesinearlyDobrotivianstrataofPerunica,theIberianChainandArmoricanMassifreflectsanunusualdispersioneventoftarphyceridsintolowerlatitudeseascoincidingwithadistinctclimateperturbationduringtheOrdovician.

【 授权许可】

Unknown