Catherine G. Klein, Nicholas R. Longrich, Nizar Ibrahim, Samir Zouhri & David M. Martill (2016)
A new basal snake from the mid-Cretaceous of Morocco.
Cretaceous Research (advance online publication)
A new basal snake species is described from the Kem Kem beds of Morocco.
Norisophis begaa lacks an interzygapophyseal ridge and a well-developed neural spine.
It is diagnosed by parazygantral foramina, interzygapophyseal constriction, and incipient prezygapophyseal processes.
These characteristics suggest it is closely related to the Madtsoiidae, Najash, Coniophis and Dinilysia.
North Africa was a hotspot for early snake evolution in the mid-Cretaceous.
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 yield 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 snakes.