A new fossil Squamata from the Quiricó Formation (Lower Cretaceous), Sanfranciscana Basin, Minas Gerais, Brazil

The Borioteiioidea (Polyglyphanodontia) is a group of lizards commonly found in Cretaceous Laurasian deposits and is considered as the sister group of Teiidae. While the Asian record comprises several well-preserved skulls and skeletons, other Laurasian occurrences are generally known from disarticulated skull material and isolated teeth. Additionally, the Gondwanan record is rare, with only one species described so far, Bicuspidon hogreli, from the Ifezouane Formation, Kem Kem Beds of Morocco. Given their wide geographic distribution, several biogeographic hypotheses were suggested to explain the temporal and spatial distribution of borioteiioids. In this study, we report the first record of a borioteiioid from the Lower Cretaceous of South America. The specimen was unearthed from Aptian deposits of the Quiricó Formation (Sanfranciscana Basin), Brazil, and consists of both anterior portions of dentaries. Among other characteristics, the material has transversally wide mid-posterior teeth with two distinct cusps (labial and lingual), as typically seen in species of the genus Bicuspidon. It also exhibits additional features, such first mental foramen facing anteriorly and the remaining ones forming a line in the lateral portion of the dentary, anterior symphyseal process extending from the anterior margin of the symphysis, and symphysis bearing an oval-shaped and thick process. These characteristics allowed us to erect a new species of Borioteiioidea, Cryptobicuspidon pachysymphysealis gen. et sp. nov. Cryptobicuspidon pachysymphysealis is one of the oldest records of Borioteiioidea known so far and suggests that Polyglyphanodontini borioteiioids originated in Gondwana with a posterior dispersal to North America and Europe during the Late Cretaceous. [Display omitted] •A new Polyglyphanodontini lizard is reported from Lower Cretaceous from Brazil.•The Brazilian material seems to be more related to the African occurrences.•These lizards originated in Gondwana and, during Late Cretaceous, reached Laurasia.