Anurans (Amphibia: Anura) from the Upper Cretaceous (Santonian-lower Campanian) Bostobe Formation of Northeastern Aral Sea Region, Kazakhstan

The newly collected specimens from the Upper Cretaceous (Santonian-early Campanian) Bostobe Formation at the Shakh-Shakh locality in the Northeast Aral Sea Region, Kazakhstan, increase the diversity of anurans in this stratigraphic unit and now two taxa can be recognized there: gobiatid Gobiates sp. and large anuran Discoglossidae indet. The faunal association of gobiatids + discoglossids is characteristic for Cenomanian-Campanian vertebrate assemblages of Middle Asia and Kazakhstan. In the Late Cretaceous of Asia, large sized anurans appeared in the Cenomanian and became a common element of anuran assemblages from the Turonian onwards, earlier than in North America where large sized anurans began dominating assemblages in the late Campanian.