Entofauna associada aos imaturos de simulídeos (diptera, simuliidae) em substrato vegetal de arroios da bacia do Rio Ijuí, RS, Brasil

Abstract

The present work deals with a survey of the diversity, spatial distribution and trophic relation of the entomofauna associated with the immature stages of black flies (Insecta, Diptera, Simuliidae). The main objective of the work was to establish an entomological material analysis available at the Zoology Laboratory of the Fronteira Sul Federal University, Cerro Largo, Rio Grande do Sul State, Brazil, reporting information on the fauna associated with the microhabitat of the immature stages of black flies (eggs, larvae and pupae) to provide information on predators of these insects with hematophagous habit in the adult stage and to assist in the preservation of biodiversity in programs of control of the species with sanitary importance. In this way, an investigation was carried out, in order to obtain data from biological materials collected on vegetative substratum in nine towns belonging to the northwest region of the state of Rio Grande do Sul. The methodology of the work consisted in the bibliographical revision and analysis of samples of the entomofauna associated to the immature of black flies that were obtained in 17 sample points during the months of August to October of 2015. In total, 32,156 benthic organisms were counted, being 30,457 immature stages of black flies and 1,699 individuals of the associated entomofauna. The most abundant families that compose the fauna associated with the immature of black flies were Chironomidae (859 specimens) and Hydropsychidae (612 specimens), followed by Leptohyphiidae (146 specimens), Noteridae (46 specimens), Elmidae (32 specimens) and Hydrophilidae (4 specimens). Through a specialized bibliography, it was verified which of the sampled families include predators of the immature stages of black flies. The representatives of Hydropsychidae are considered important predators of the immature stages of black flies, this being the only family widely present in the analyzed samples.