Riqueza e distribuição espacial de Ephemeroptera, Plecoptera e Trichoptera em ambientes lóticos de mata atlântica

Abstract

The knowledge of the distribution of aquatic insects is of great importance for conservation. The objective of the study was to evaluate the composition and spatial distribution of Ephemeroptera, Plecoptera and Trichoptera (EPT) fauna, in eight forested streams in southeastern Minas Gerais. Samples were collected during the dry season of 2010, and obtained 10 litter samples in riffles and 10 in pools of each stream with Surber. 5631 organisms and 49 genera of EPT were identified. The values of abundance and assemblage composition differed between streams and mesohabitats, while richness differed only between streams. Smicridae, Phylloicus, Leptophlebiidae sp1, Paragripopteryx and Anacroneuria were the taxa that most contributed to the separation of streams. Twelve taxa were recorded in greater abundance and frequency in riffles and six in pools. The study results suggest that features scale streams (water temperature, for example) and mesohabitat (heterogeneity of litter and water velocity) are determinants of variation in the structure and composition of the EPT assemblages. Keywords: Preservation