New teeth of Archosauria from Laje do Coringa, Alcântara Formation (Cenomanian): morphological study and taxonomic identification

• Grant number: 24/17915-6
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: February 01, 2025
• End date: January 31, 2026
• Field of knowledge: Biological Sciences - Zoology - Paleozoology
• Principal Investigator: Marcelo Adorna Fernandes
• Grantee: Andrey Lincoln Marcelino de Oliveira
• Host Institution: Centro de Ciências Biológicas e da Saúde (CCBS). Universidade Federal de São Carlos (UFSCAR). São Carlos , SP, Brazil

Abstract

The Alcântara Formation (Cenomanian, São Luís Basin), located on the northeast coast of the country, represents one of the most important geological units of the Upper Cretaceous of Brazil. A wide range of fossil fauna of "fish" and Tetrapoda are commonly found in this region, including Pterosauria, Crocodyliformes and at least two lineages of Dinosauria. Many of the fossil records from this formation are represented by isolated teeth and/or fragmented materials with a high level of disarticulation, which makes accurate taxonomic identifications of isolated materials an even more challenging task. In this sense, little attention has been directed to materials from this region with regard to the application of combined methodologies, as they also lack more detailed anatomical descriptions. Therefore, this project proposes the use of combined methods, using discriminatory and phylogenetic analyzes in the taxonomic identification of around 60 isolated dental crowns, all of which are unpublished materials. Preliminarily, at least three dental morphotypes/clades can be noted, thus demonstrating the potential results of the proposal. From the execution of the research, it is expected that the use of qualitative approaches in the identification of isolated teeth, including the detailed study of macro and microanatomical aspects, will help in filling gaps related to the fossil records of the Alcântara Formation.