This study investigated the structure of the Oligochaeta and Chironomidae assemblages associated with monospecific stands of two submerged macrophyte species: Egeria najas and Hydrilla verticillata. Samplings were carried out in Leopoldo Backwater and Paraná river, in August 2008. To assess the structure of Oligochaeta and Chironomidae assemblage in each macrophyte we calculated: species density, richness, diversity, and evenness. A detrended correspondence analysis (DCA) was used to summarize Oligochaeta and Chironomidae assemblages composition. The highest values of species density and richness for the two groups were recorded in H. verticillata. Although there were no significant differences in density, richness and Shannon diversity, the assemblage... |