Albanerpetontid amphibians from the Late Cretaceous (Santonian) of Iharkút, Hungary, with remarks on regional differences in Late Cretaceous Laurasian amphibian assemblages

Abstract

Since its discovery in 2000, the Iharkút fossil locality in the Upper Cretaceous (Santonian) Csehbánya Formation of western Hungary has yielded a taxonomically diverse assemblage of terrestrial and freshwater vertebrates that continue to provide insights into the diversity, paleobiogeography, and paleoecology of Late Cretaceous vertebrates in Europe. Albanerpetontidae, an extinct group of superficially salamander-like amphibians that were widespread across Laurasia during the latter part of the Mesozoic, are represented at Iharkút by 16 fragmentary jaws. Here we describe and figure these specimens as Albanerpetontidae genus and species indeterminate. Based on the age of the Iharkút locality, several premaxillary features, the known distribution (late Early Cretaceous – late Pliocene) of the type genus Albanerpeton, and an unusually large dentary specimen, we suggest that the Iharkút albanerpetontid may pertain to a previously unrecognized species of Albanerpeton, but verification of that must await the recovery of more diagnostically informative specimens, such as frontals and more nearly complete premaxillae. The Iharkút lissamphibian assemblage contains a mixture of taxa with Laurasian (the albanerpetontid and a discoglossid anuran) and Gondwanan (a neobatrachian anuran) affinities. Intriguing higher level differences are evident among Late Cretaceous Laurasian assemblages; for example, urodeles are scarce or absent (as at Iharkút) in Europe, whereas albanerpetontids are scarce in Middle Asia.