A new Sphagesaurus (Mesoeucrocodylia: Notosuchia) from the Upper Cretaceous of Monte Alto City (Bauru Group, Brazil), and a revision of the Sphagesauridae

Abstract

Since the description of Sphagesaurus, mostly dental material has been reported, apart from two incomplete skulls. Here we describe a new species of Sphagesaurus, from Monte Alto City, Southeastern Brazil, which includes the skull and most of the mandible. Distinctive characters (e. g. antorbital fenestra; robust quadrate; anterior mandibular teeth incisiform; ornamented sulcate palate) allow differentiation from S. huenei. Several characters allow assignment to the genus Sphagesaurus (e. g. teardrop-like oblique molariform teeth), while new information is provided (e. g. premaxilla, pterygoid and mandible morphology; jugal foramen; occipital surface; battery of mandibular teeth). A revision of the Family Sphagesauridae Kuhn 1968 is given. A preliminary phylogenetic analysis supports a sister-taxon relationship for S. huenei and the new species. The phylogenetic relationship of notosuchians is explored. Sphagesaurids were terrestrial notosuchians that evolved during the Upper Cretaceous of South America, known only from the Adamantina Formation, Campanian-Maastrichtian (Upper Cretaceous) from Brazil.