Utilização de leptagrion siqueirai (odonata: coenagreonidae) como controladores biológicos de larvas e pupas de mosquitos vetores de doenças.

Abstract

The immature forms of odonata live in a wide variety of aquatic habitats. The nymphs of L. siqueirai occupy mainly epiphytic and terrestrial bromeliads and are obligate predators throughout their existence. In this environment, they feed mainly on larvae and pupae of Diptera of the families Culicidae and Chyronomidae. The present work aims to study the seasonal age and abundance, as well as the use of L. siqueirai nymphs in the control of larvae and pupae of disease vector mosquitoes. The study was carried out in a rubber tree (Hevea brasiliensis.) plantation located inside the Faculdade de Ciências Agrárias do Pará (FCAP). The rubber trees are arranged in a stand with 24 rows, spaced at 6.0 meada, totaling an area of approximately 1.5 ha. The nymphs of L. siqueirai were captured in epiphytic bromeliads of the species Aeehmea tinctoria, which were attached to almost all rubber trees in the area. The abundance of these insects was related to the season, distance from the edge of the forest, size of the bromeliad and amount of water contained in the bromeliad. Four species of Culicidae, one species of Coenagreonidae, two species of Chryronomidae and one species of Toxorhynehites were recorded. Collections were made in the less and more rainy seasons. According to Lounibos (1956), working with 160 of A. nudicaulis, he found an average of 7 individuals of L. siqueirai. In our work with 40 specimens of Aeehmea tinctoria, we found an average of 11 individuals of L. siqueirai per plant. Regarding the other insects, Lounibos (1956) found about six families comprised in two orders. Here six orders were found with about 17 families.