Aiming to improve the knowledge on the Brazilian biodiversity, especially the ant fauna of Rio Grande do Sul State (Southern Brazil), this survey was conducted in the Praia da Pedreira, a site of Intensive Use of the Parque Estadual de Itapuã. Ground-dwelling ant species were surveyed for three environments in the beach (native forest, rock bar and sand bar), during 12 months (April/2000 - March/2001). Collections resulted in 60 species belonging to 24 genera, 18 tribes and eight subfamilies (Dolichoderinae, Ecitoninae, Ectatomminae, Formicinae, Heteroponerinae, Myrmicinae, Ponerinae and Pseudomyrmecinae). According to the first order jackknife estimator, the native forest area presented the greatest richness (Sest= 37.5), followed by rock bar (Sest= 8.9) and sand bar (Sest= 5.9). Only Acromyrmex laticeps, Crematogaster sp. and Solenopsis invicta were common to all three environments. This paper presents the first record of Pachycondyla crenata and Pachycondyla laevigata (Ponerinae) occurrence in the Rio Grande do Sul State.
Biodiversity; epygeous ant fauna; Formicidae; Insecta
