Occurrence of ants (Hymenoptera: Formicidae) in both leaf litter and twigs in Atlantic forest

Abstract

Twigs in the litter derived from the fragmentation of tree branches form one microhabitat, where entire colonies of ants, both leaf litter and arboreal species, can be found. The objective was to survey ant species that are present in both the leaf litter and twigs simultaneously. We describe the nest type, the social structure of the colonies and the trophic guild membership of these species. Samples were collected from 10 preserved fragments of Brazilian Atlantic forest. We used Berlese funnels to collect leaf litter ants and manual collection for twig ants. We recorded 80 ant species; 60 species were in leaf litter samples and 35 species were in twigs. Of the total species, only 15 (20%) occurred simultaneously in the leaf litter and in twigs. Of these species, Gnamptogenys striatula, Pheidole sarcina, P. sospes and Solenopsis sp. 2 were the most frequent among leaf litter dwellers, and Myrmelachista catharinae was the most common arboreal species. Most of these belonged to generalist and predator guilds, with "polydomous nests" and colonies monogynous.