Silurian carcinosomatid eurypterids from the Prague Basin (Czech Republic)

Bulletin of geosciences

Budil P¹  Manda Å ¹  Tetlie OE¹ 

关键词: Eurypterida;    Carcinosomatidae;    Prague Basin;    Wenlock;    Přídolí;   

DOI  :  

来源: Czech Geological Survey

【 摘 要 】

TheeurypteridrecordfromthePragueBasinincludesoccasionalLudlowfaunas,butintheuppermostSilurian(Přídolí)eurypteridssuddenlybecomecommoninrelativelydeepwaterfacies.PterygotidsclearlydominatetheselateSilurianfaunas,whereascarcinosomatidsarerepresentedbythesinglespeciesEusarcanaacrocephala,knownfromonlyafewspecimens.Thisspeciesisrevisedanditsvalidityisdiscussedherein.AneweurypteridfaunafoundindeepwatershalefaciesisdescribedfromthelowerandmiddlepartoftheMotolFormation,Wenlock,Sheinwoodian-Homerian,CyrtograptusmurchisonitoC.lundgrenigraptolitebiozones,atPraha-Lochkov.ItconsistsofcommonfragmentsofthecarcinosomatideurypteriddescribedhereasEusarcana?sp.Aandrarepossiblepterygotidfragments.ThisistheearliestevidenceofcarcinosomatidsoutsideLaurentiaandoneoftheearliestrecordsofthegroupworldwide.ThisearlyoccurrenceoutsideahypotheticalLaurentianevolutionarycentreisdiscussedwithrespecttothepalaeobiogeographyofotherfaunascolonisingperi-GondwananbasinsafterthedeclineofwidespreadearlySiluriananoxia.Aprevioussuggestionthatcarcinosomatids(presumedbasalmembersoftheCarcinosomatoidea)hadsimilardistributionpatternstopterygotoidsisdiscussed.Eurypteridsmigratedintotheperi-Gondwananrealmfromthetropicalzone,butthedispersionpotentialofcarcinosomatidsintothetemperateandcoolwaterrealmwasprobablylowerthanthatofpterygotids.InthePragueBasin,thecarcinosomatid-dominatedfaunaoftheWenlockagewasreplacedinthelateSilurianbyapterygotid-dominatedfauna.

【 授权许可】

Unknown