Observations on the palate and choanae structures in Mesoeucrocodylia (Archosauria, Crocodylomorpha): Phylogenetic implications

Abstract

The palate and choanae structures are important to the study of the evolution in Crocodylomorpha. Notosuchians, sebecosuchians and other Mesoeucrocodylia show a considerable diversity of patterns. Some notosuchians (Mariliasuchus, Notosuchus, Sphagesaurus) possess important similarities with at least one sebecosuchian (Stratiotosuchus), especially the triangular-subtriangular choanae, and the exclusion of the pterygoid from the posterior border of the suborbital fenestra. The use of these characteristics may represent useful information in phylogenetic analysis and should always be described in detail.