Aiming to determine if the vegetation structure affects the local and regional richness and community structure of predator beetles (Histeridae), four habitats established on sandy soils (restingas and pasture) in Espírito Santo State, Brazil, with a structural complexity gradient and showing varying degrees of disturbance were surveyed with pitfall-baited traps (human and horse dung). Eight histerid species were registered. The species richness was almost equal in all habitats (4 to 5 species), and there was no significant difference in diversity and equitability. Although not significantly different in diversity, the communities could be considered different due to the gradual substitution of the dominant species and composition. The species substitution pattern was related to the change in vegetation physiognomy, which seems to impose barriers to the odour dispersion, affecting resource location, and allowing rare (but more efficient in resource localization) species to be maintained in the community. The local richness of histerids in pasture and in different physiognomies of restinga is similar and low due to the ephemeral nature of decaying resources, which impose a limit to the number of species that get to the resource. Its spatial and temporal unpredictability, by its turn, allows both common and rare species to remain in the community, the first through numeric advantage and the last through an eventual superiority in finding the resource.
Community structure; dominance shift; ephemeral resource
