First record of the hexanchoid shark genus Crassodontidanus (Chondrichthyes: Hexanchiformes) from the Jurassic of Hungary (Mecsek Mts, Southern Hungary), with a summary of the hexanchiform fossil record of Hungary

The first occurrence of Crassodontidanidae of Hungary is described. The material consists of a single tooth, currently placed in private collection. Th e specimen was found nearby Magyaregregy, at the so-called Síngödör outcrop, in the Middle Jurassic (Bathonian) Óbánya Limestone Formation. The tooth is characterized by a serrated mesial cutting edge of the main cusp, high root with convex mesial and distal margins. This character combination readily distinguishes the tooth from those of Hexanchidae. Currently, this is the oldest representation of Hexanchiformes in the fossil record of Hungary, which widens our knowledge on the distribution patterns of Crassodontidanidae. Summarized data of the hexanchiform fossil record of Hungary is also detailed here. The data show the presence of 3 families (Crassodontidanidae, Hexanchidae, Heptranchidae) with 5 genera (Crassodontidanus, Notidanodon, Hexanchus, Notorynchus and Heptranchias) from the Bathonian (Jurassic) to the Badenian (Miocene). With 22 fi gures and 1 table.