Prevalencia de anofelinos (Diptera: Culicidae) no crepusculo vespertino em areas da usina hidreletrica de Itaipu, no municipio de Guaira, Estado do Parana, Brasil / Prevalence of anophelines (Diptera: Culicidae) during sunset in areas of the Itaipu hydroelectric usine in Guaira county, State of Parana, Brazil

ABSTRACT

Systematic collections of anophelines were conducted from November 1994 to August 1995 from 1800 to 2000 hr using Shannon traps and human-bait along the lake margin which forms the Itaipu hydroelectric reservoir, State of Parana, Brazil. Species prevalence was studied at 15 min intervals. Anopheles albitarsis sensu latu and An. galvaoi, were the most frequently collected mosquitoes. All Anopheles species populations peaked between 1845 and 1930 hr. The observations illustrate the existence of a haematophagic activity cycle during the early evening hours exogenous stimulus (the beginning of sunset) - Shannon trap (light attraction) - human bait (haematophagy) - rest and digestion - exogenous stimulus - Shanon trap or surrounding vegetation. The grater abundance of An. albitarsis collected in human-bait and Shannon trap suggests it may be a potencial malaria vector in the region.