Diversity and structure of dung beetle (Coleoptera: Scarabaeidae) assemblage in natural grasslands of the Brazilian Pantanal

Dung beetles (Coleoptera: Scarabaeidae) provide essential ecological functions in the ecosystems they inhabit, acting in nutrient cycling, parasite control and, seed secondary dispersal. In addition, they are widely used as indicators of environmental changes. Here, we evaluated the dung beetle assemblages’ diversity and structure in the natural grasslands of the Brazilian Pantanal. We sampled dung beetles in January/February 2016 in 24 natural grassland sites historically influenced by seasonal flooding in Aquidauana, Mato Grosso do Sul, Brazil, using pitfall traps baited with carrion and cattle dung. In all, 1632 individuals from 32 species of dung beetles were collected. Eleven species were considered generalists, nine coprophagous and, nine necrophagous, indicating that diet generalism may be more successful than diet specialization in this ecosystem. Small tunneler beetles had higher species richness and abundance, while large tunneler beetles had higher biomass. Finally, the high richness of dung beetles found in natural grasslands, historically influenced by seasonal flooding, underscores the importance of research studies on this ecosystem in which the dung beetle fauna is still poorly known. Additionally, this result shows the importance of natural grasslands for conservation of dung beetle biodiversity in the Brazilian Pantanal.