Allain, R., Tykoski, R., Aquesbi, N., Jalil, N.-E., Monbaron, M., Russell, D., and Taquet, P. 2007. An abelisauroid (Dinosauria: Theropoda) from the Early Jurassic of the High Atlas Mountains, Morocco, and the radiation of ceratosaurs. Journal of Vertebrate Paleontology 27(3):610-624.

Abstract: The fossil record of abelisauroid carnivorous dinosaurs was previously restricted to Cretaceous sediments of Gondwana and probably Europe. The discovery of an incomplete specimen of a new basal abelisauroid, Berberosaurus liassicus, gen. et sp. nov., is reported from the late Early Jurassic of Moroccan High Atlas Mountains.

Phylogenetic analysis recovers Ceratosauroidea and Coelophysoidea as sister lineages within Ceratosauria, and Berberosaurus as a basal abelisauroid. Berberosaurus is the oldest known abelisauroid and extends the first appearance datum of this lineage by about 50 million years. The taxon bridges temporal, morphological, and phylogenetic gaps that have hitherto separated Triassic to Early Jurassic coelophysoids from Late Jurassic through Cretaceous ceratosauroids. The discovery of an African abelisauroid in the Early Jurassic confirms at least a Gondwanan distribution of this group long before the Cretaceous.

Jenny and colleauges (1980) and Taquet (1984) briefly reported another theropod from the late Early Jurassic of the Moroccan High Atlas. This specimen comes from the Toarcian Wazzant Formation and is currently under preparation in the Muséum National d’Histoire Naturelle, in Paris. It differs clearly from Berberosaurus in its smaller size, the longer cervical vertebral centra, and the absence of a sulcus on the medial surface of the fibula.

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