The Rhinella fossil record for South America: description of unpublished specimens, taxonomic review and phylogenetic position

Abstract

Rhinella is one of the most diverse genera of frogs in the nearly cosmopolitan Bufonidae family. Rhinella species are widely distributed throughout South America, inhabiting a wide range of environments and ecoregions. Several efforts have been made to elucidate and better understand the evolutionary relationships within the genus. However, previous phylogenetic analyses have not included its fossil representatives. Currently, fossils associated with Rhinella lack an adequate diagnosis, with most of them simply being associated with Bufonidae or ambiguously with Rhinella based on insufficient osteological characters, considering the current variation within the genus. Thus, an analysis based on morphological and molecular data that encompasses taxa from all major clades of Rhinella, including fossils, is necessary for a better understanding of the group's evolutionary history. In this context, the main objectives of this project are: (1) to understand the osteological variations within the genus Rhinella, (2) to describe specimens associated with Bufonidae/Bufo/Rhinella from the Itaboraí Basin (Brazil), the Honda Group (Colombia), and the Tarija and Ñuapua formations (Bolivia), and (3) to develop a phylogenetic proposal for Rhinella using Total Evidence, aiming to determine the phylogenetic position of all related fossil specimens. (AU)