Composition of ant fauna (Hymenoptera: Formicidae) at litter in areas of semi-deciduous forest and Eucalyptus spp., in Southeastern Brazil

Abstract

This study aimed to evaluate the composition of the litter ant fauna in areas of semi-deciduous forest with eucalyptus plantations without management during different ages. Four sites were studied, three with eucalyptus and one with native vegetation, all located in the Municipality of Rio Claro (São Paulo State), Southeastern Brazil. At each site, 100 samples of 1 m² of leaf litter were collected, comprising the dry and wet seasons. Each sample was submitted to a mini-Winkler extractor for 48 hours. In total, 58,410 ants were sampled, distributed in 10 subfamilies, 42 genera and 120 morphospecies/species. Among them, 85 species were found in semi-deciduous forest, and 84 in the Eucalyptus tereticornis forest with 100 years without management. While in the forests of E. tereticornis and E. urophylla with 22 years without management, we recorded 73 and 56 species, respectively. Based on previous studies, this survey provided the record of over 16 genera and 24 species previously unknown for the studied region, with three exotic species. The samples ordination using the non-metric multidimensional scaling (NMDS) indicated difference in the similarity between the samples, especially those from the E. urophylla forest. Beyond the period without management, the presence of allelopathic substances in the litter may be interfering in the number of species and in the communities. The results evidenced the importance of old-growth forests of eucalyptus for the maintenance of ant's diversity in a region where native vegetation is scarce.