A new basal snake from the mid-Cretaceous of Morocco

Fossil snakes are relatively well represented in the Upper Cretaceous of northern Africa, with material known from Morocco, Sudan, Egypt, Libya, Algeria, and Niger. The Moroccan Kem Kem beds have yielded a particularly diverse snake assemblage, with Simoliophiidae, Madtsoiidae, ?Nigerophiidae and several unnamed taxa co-occurring. These fossils are important for our understanding of the early evolutionary history of snakes, and may shed light on the ecology and initial diversification of basal snakes. We describe a new taxon, Norisophis begaa gen. et sp. nov., from the Kem Kem beds of Begaa, in southeast Morocco. It is characterised by a marked interzygapophyseal constriction, parazygantral foramina, an incipient prezygapophyseal process, and an anterio-posteriorly short centrum. Several characteristics shared with Najash, Seismophis, Madtsoiidae, and Coniophis suggest that Norisophis is a stem ophidian. N. begaa further increases the diversity and disparity of snakes within the Kem Kem beds, supporting the hypothesis that Africa was a mid-Cretaceous hotspot for snake diversity.