A reworked elasmobranch fauna from Tunisia providing a snapshot of Eocene-Oligocene Tethyan faunas

A post-Priabonian fluviatile debris-flows in Mabrouk (MBK), Djebel Chambi – Tunisia, have yielded a surprisingly rich assemblage of reworked marine elasmobranchs (23 taxa of sharks and rays). By comparison with their sub-coeval counterparts from northeastern Africa, this assemblage suggests an age ranging from the latest Priabonian up to the earliest Rupelian for the close marine deposit from where they were likely reworked. Moreover, it highlights the widespread east-west distribution of sharks and rays along North African coasts, a distribution that reflects the existence of roughly similar tropical environmental conditions in northern latitudes of Africa at that time. This discovery indicates that the Neotethysian elasmobranch communities remained particularly well diversified around the global cooling recorded at the Eocene/Oligocene transition.