A new fossil frog (Lissamphibia: Anura) from the Late Cretaceous of Brazil and the early evolution of neobatrachians

Abstract

Abstract Although neobatrachians represent about 95% of anuran diversity, their fossil record, especially during the Mesozoic, remains scarce and often limited to a few damaged specimens with uncertain affinities. In South America, fossil neobatrachians have been identified from the Cretaceous deposits in Chile, Argentina, and Brazil. Here, we describe a new species of fossil neobatrachian from the Late Cretaceous (Campanian) Bauru Basin, south-eastern Brazil, based on several well-preserved specimens. The morphology of the new species was described in detail using high-resolution micro-CT, and its taxonomic affinities were investigated through a phylogenetic analysis encompassing both living and extinct taxa. The new taxon was recovered among hyloids, more specifically as closely related to other well-ossified taxa. However, due to the lack of any synapomorphies with extant families, we were unable to assign the new species to a more specific group within Neobatrachia. The discovery of a new fossil frog in the Late Cretaceous Bauru Basin significantly enhances our understanding of neobatrachian early morphology during the Late Cretaceous of South America.