A new crocodylian (Archosauria) from the basal Paleocene of the Red Deer River Valley, southern Alberta

Borealosuchus griffithi, sp. nov., is described on the basis of an incomplete skeleton from the basal Paleocene, southern Alberta. This new species records one of a few basal Cenozoic occurrences of Crocodylia so far known. B. griffithi is most distinctive in having a markedly laterally concavo-convex snout; a deep, elongate recess or fossa on the anteroventral surface of the jugal; and a large, nearly rectangular incisive foramen. Within Borealosuchus, B. griffithi probably takes a "more crownward" position than does B. sternbergii of the late Late Cretaceous. With additional information from the new species, the diagnosis of Borealosuchus is revised.

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