Higher Diversity in Open Cerrado Supports the Role of Regional Processes in Shaping an Anuran Assemblage in Southeastern Brazil

Abstract

In this study, we evaluate the role of local and regional factors in shaping the anuran assemblages in the Cerrado biome by contributing to the knowledge on the diversity patterns of different Cerrado vegetation types in southeastern Brazil. We measured richness and abundance of ground dwelling frogs in a gradient of vegetation structural complexity, varying from grassland (campo sujo) to forest (cerradao), using pitfall traps with drift fences and standardized efforts. We also measured vegetation structure by directly counting its components in the field. We found differences in richness and abundance among vegetation types, with richness being higher at more open vegetation types, and abundance being higher at the forest due to the extremely high number of captures of Rhinella ornata, a species from the Atlantic Forest biome. A concordant pattern in anuran diversity and vegetation structure suggests an important role of the habitat in structuring diversity in this group, with open vegetation types sharing both more similar anuran assemblages and vegetation. The higher diversity of Cerrado anurans observed in the open vegetation types in southeastern Brazil is in phase with diversity accounts for other groups of the herpetofauna throughout the biome, and it supports a prevalence of the regional processes over local determinism, a hypothesis that should be formally tested for amphibians with large-scale standardized sampling.