A new and complete peirosaurid (Crocodyliformes, Notosuchia) from Sierra Barrosa (Santonian, Upper Cretaceous) of the Neuquén Basin, Argentina

Abstract

A new peirosaurid crocodyliform from the Upper Cretaceous (Santonian) of South America, Barrosasuchus neuquenianus gen. et sp. nov. is here described. Barrosasuchus is distinguished by a combination of features that include: presence of a foramen at the mid-point of the dorsal surface of the mandibular symphysis; quadratojugal dorsally broad, extensively contacting the postorbital articulation; absence of ventral exposure of splenials along mandibular rami, posterior to the symphysis; mid to posterior teeth with roots and crowns highly compressed laterally; presence of longitudinal depressions on palatal surface of maxillae; and anterior dentary alveoli strongly procumbent. The holotype specimen of Barrosasuchus neuquenianus, MCF-PVPH-413 is represented by an almost complete skull and most of the articulated postcranial skeleton. Thus, Barrosasuchus is currently the most complete peirosaurid taxon known from Patagonia, and represents a key element for future reviews of the phylogeny of the group. Peirosauridae represents a successful clade in Gondwana, and particularly in Patagonia, with at least six distinct genera currently recorded.