Preliminary overview of late cretaceous turtle diversity in Eastern Central Europe (Austria, Hungary, and Romania)

Abstract

A preliminary overview of the relatively poorly known Late Cretaceous turtle faunas from eastern Central Europe is given, including brief descriptions both of historically significant and of more recently collected taxa and specimens from the Santonian-Campanian of Hungary, the Campanian of Austria, and the Maastrichtian of Romania. Eastern Central European Late Cretaceous turtle faunas are similar to contemporaneous Western European faunas in their low taxonomic diversity and in being composed almost exclusively of continental forms that are considered endemic to Europe. The eastern Central European fauna includes two pleurodire lineages: the primitive Dortokidae, represented by a separate regional lineage that includes Dortokidae gen. et sp. nov. from the Maastrichtian of Transylvania (Romania) and other indeterminate dortokids from the Santonian of Hungary and Campanian of Austria; and the Bothremydidae, represented by Foxemys sp., a member of the Foxemydina that otherwise is known only from Western Europe. Cryptodires are represented by a conservative turtle, Kallokibotion bajazidi (Nopcsa, Quarterly Journal of the Geological Society of London 79:100–116, 1923a), from the Maastrichtian of Transylvania and by other previously unknown or unrecognised, closely related taxa from the Santonian of Hungary and the Campanian of Austria. The absence of Kallokibotion in Western Europe, coupled with the presence in both regions of the bothremydid Foxemys and of separate dortokid lineages, indicate that turtle faunas in Western and eastern Central Europe were partially separated from one another during the Late Cretaceous. “Senonemys suemegensis” (Bohn, Földtani Közlöny 96:111–118, 1966) is the only turtle known from Upper Cretaceous marine rocks in eastern Central Europe, but because the material was not adequately described and it now appears to be lost, the identity and relationships of this taxon remain unknown. Many of the turtle-bearing localities in eastern Central Europe show differences in the relative abundances of specimens and faunal compositions that likely are due to a combination of ecological and biogeographical factors and regional extinctions.