Composição de macroinvertebrados bentônicos associados ao ambiente de simuliidade (diptera, nematocera), em afluentes do Rio Piratinim, Bacia do Rio Uruguai, Rs, Brasil

Abstract

The present work deals with a research on the diversity, spatial distribution and trophic relationship of benthic macroinvertebrates in the microhabitat of Simuliidae (Diptera, Nematocera) and has as main objective to know predators of the immature forms of these insects, that present hematófago habit in the adult phase. Samples of macroinvertebrates were collected on vegetation substrates and rocky bottoms, in rapids stretches of six tributaries of the Piratinim River, Uruguay River Basin, RS, Brazil. In addition, a literature review was carried out on the fauna associated with the microhabitat of the immature forms of Simimidae (eggs, larvae and pupae) in order to provide information on predators of these insects. The analysis of biological organisms obtained in eighteen collection points, during the months of September to November of 2017, resulted in 9,036 individuals, being 7,302 representatives of Simuliidae and 1,734 associated benthic macroinvertebrates. The most abundant families in the community composition of the benthic macroinvertebrates of the immature forms of simuliids were Chironomidae (511 specimens), Hydropsychidae (508 specimens), Baetidae (445 specimens), Elmidae (216 specimens), Staphilinidae (26 specimens), Leptophlebiidae (22 copies), Psephenidae (5 copies), Ceratopogonidae (1 copy). Among the simulídeos predators are the representatives of Hydropsychidae.