Diversidade e distribuição de larvas de Odonata (Insecta) no Rio Sarandi, no sudoeste do Paraná, Brasil

Abstract

We evaluate the distribution of Odonata larvae along the longitudinal gradient Sarandi River, as well as environmental integrity through the richness and composition. We sampled the larvae of December/2014 to November/2015 at six sites, using qualitative/quantitative samples with sieves and sampling effort 40 minutes/person/sites. We identify the larvae in terms of genera. We measure the variables of water: pH, electrical conductivity, dissolved oxygen, alkalinity, biochemical oxygen demand (BOD) and water temperature. In addition, the structural variables depth, river width and current velocity. Environmental variables sites out that the sampling sites varied significantly (p <0.05) compared to pH, electrical conductivity, current velocity, depth and width. We observed clear separation by ACP, the source in relation to the other sites, due to its smaller depth, current velocity, pH and conductivity. Identified 544 individuals, distributed in 24 taxa, represented by the suborder Anisoptera and Zygoptera. Progomphus sp. (Gomphidae) was the most abundant genus, followed by Hetaerina sp. (Calopterygidae). Progomphus sp. and Phyllocycla sp. they were the only taxa present at every sites sampled during the study period. We recorded higher abundances in the sites P1 and P2 and greater wealth in the sites P2 and P6. The larvae of Odonata were associated conditions the integrity of habitats, such: presence of marginal vegetation, bed stability, flow and type of land use. Recorded greater richness, abundance, diversity index and equity in more sites upstream, which are above the urban areas.