Diversity of dung beetles in three vegetation physiognomies of the Caatinga dry forest

Abstract

Caatinga is the largest continuous Seasonally Tropical Dry Forests (STDF) in America, with a wide variety of vegetation physiognomies. Understanding how biodiversity is structured in each ecosystem allows to define what set of species and species attributes thrives under different vegetation physiognomies. We compared dung beetle diversity and functional groups in three physiognomies (Caatinga sensu strictu, Grota and Cerrado) within a mosaic of Caatinga during the rainy season. A total of 1073 dung beetles from 14 species were collected. Cerrado had a higher species richness than the other physiognomies. Alpha, gamma and beta diversities were statistically higher in Cerrado and Grota, while Caatinga sensu strictu was the least diverse physiognomy. Dung beetle expected species richness, abundance, and body size were similar among the physiognomies. In Cerrado and s. strictu diet-generalist dung beetles had a clearly higher species richness and abundance than the coprophagous and necrophagous dung beetles. This may indicate that diet generalists may be more successful than diet specific species in this ecosystem. Our study provides cues supporting that each physiognomy harbors distinct dung beetle communities, which this may be related to different microhabitat conditions and food availability.