Patterns and processes of diversification of the psamophilous reptiles from the paleodunes of the middle São Francisco River

• Grant number: 17/10000-9
• Support type: Scholarships in Brazil - Post-Doctorate
• Effective date (Start): August 01, 2017
• Effective date (End): November 02, 2021
• Field of knowledge: Biological Sciences - Zoology - Taxonomy of Recent Groups
• Principal researcher: Miguel Trefaut Urbano Rodrigues
• Grantee: Renato Sousa Recoder
• Home Institution: Instituto de Biociências (IB). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Associated scholarship(s): 18/23368-7 - Patterns and processes of diversification of the psamophilous reptiles from the paleodunes of the middle São Francisco River, BE.EP.PD

Abstract

In the middle course of the São Francisco River, inserted in the semiarid Caatingas of northeastern Brazil, there is an extensive field of continental paleodunes, in which a diverse fauna of psamophilic reptiles, with high proportion of endemisms, was discovered. Based on the geomorphological, paleoclimatic, and distributional patterns congruent among different reptile lineages, a vicariant diversification scenario was proposed for the fauna of the region. In this model, after an endorreic phase during the last glacial maximum, the São Francisco River made way for the Atlantic Ocean through the dunes separating the ancestral population of at least four lineages of reptiles in opposite margins. Molecular studies with populations of the lizards Eurolophosaurus (Tropiduridae), Calyptommatus and Nothobachia (Gymnophthalmidae) show a partially concordant pattern with the vicariant model, but estimates basal divergences prior to the Pleistocene. The present project proposal aims to comparatively investigate patterns of diversification of seven lineages of reptiles from the dunes based on temporally calibrated phylogenies to evaluate the role of the São Francisco River in the process of diversification of the psamophilous fauna. Second, to use a molecular approach at the genomic level, focusing on pairs of reptile species from three main dune fields, to quantitatively test the vicariance speciation model. (AU)