This paper describes the richness, composition and occurrence patterns of the epigaeic ants in native field areas. Eight field plots were sampled, in which two 100 m transects, distanced 50 m from each other, were traced. Along those transects, at every 10 m, pitfalls and sardine baits at intervals of two meters, were installed totalizing 20 pitfalls and 20 baits per plot. Additional collecting was performed by manual ant capture on the ground. In total 32 species of epigaeic ants were collected, distributed in 16 genera, 12 tribes and five subfamilies. By comparing the observed richness with the estimated richness for pitfalls as well as for baits, the numbers of collected species represented, respectively, 79.4% and 69.4% of the total estimated community. One species of the Formicinae subfamily, Acropyga goeldii, has been recorded for the first time in Rio Grande do Sul.
Acropyga goeldii; ant fauna; epigaeic ants; inventory
