Selachians from the type Campanian area (Late Cretaceous), Charentes, western France

Abstract

The stratotypical Campanian of the northern Aquitaine Basin has yielded a relatively rich and diverse selachian fauna. This fauna consists of 20 taxa, two of which represent new species: Carcharias adneti sp. nov. and Rhombodus carentonensis sp. nov. Additionally, one new combination is proposed: Serratolamna khderii (Zalmout and Mustafa, 2001) comb. nov. The discovery of Rhombodus in the Campanian constitutes the earliest occurrence of the genus and may have widespread biostratigraphical implications. The fauna corresponds to a mixture of Tethyan and Boreal species resulting from the particular palaeogeographical situation of Charentes during the Late Cretaceous. The succession of the selachian faunas from the Middle to Late Campanian shows an association mainly dominated by Boreal species (e.g., Carcharias latus) that becomes progressively influenced by immigrations of typical Tethyan components (e.g., Serratolamna khderii). It provides evidence of palaeogeographical, palaeoenvironmental and palaeoclimatical changes that occurred in the region at the end of the Campanian.