Prevalência de Anofelinos (Diptera: Culicidae) no Crepúsculo Vespertino em Áreas da Usina Hidrelétrica de Itaipu, no Município de Guaíra, Estado do Paraná, Brasil

<abstract language="eng">Systematic collections of anophelines were conducted from November 1994 to August 1995 from 18:00 to 20:00 hr using Shannon traps and human-bait along the lake margin which forms the Itaipu Hydroelectric reservoir, State of Paraná, 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 18:45 and 19:30 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 ® Shannon trap or surrounding vegetation. The greater abundance of An. albitarsis collected in human-bait and Shannon trap suggests it may be a potential malaria vector in the regio

Culicídeos do lago de Itaipu, no rio Paraná, Sul do Brasil Culicidae of Itaipu lake, Paraná River, southern Brazil

De janeiro a dezembro de 1991 foram realizadas capturas mensais de culicídeos, no Município de Guaíra, Estado do Paraná (Brasil), na margem esquerda do lago de Itaipu, ao lado da via de acesso que conduzia aos Saltos das Sete Quedas, usando-se armadilha luminosa de Shannon, e isca humana em área urbanizada. Obtiveram-se informações sobre a fauna culicidiana, as espécies prevalentes, a variação sazonal, o horário de maior densidade e a afinidade dos mosquitos em relação ao hospedeiro humano. Foram identificadas 41 espécies de culicídeos dos gêneros Anopheles, Aedes, Aedomyia, Coquillettidia, Culex, Mansonia, Psorophora e Uranotaenia. Capturaram-se 21.280 mosquitos em armadilha de Shannon e 1.010 em isca humana. As espécies mais freqüentes em armadilha de Shannon - Coquillettidia shannoni, Mansonia humeralis, Anopheles triannulatus, Aedes scapularis e Anopheles albitarsis - perfizeram 82,78% dos mosquitos capturados. Em isca humana Aedes scapularís, Mansonia humeralis e Anopheles albitarsis, somaram 91,21% dos insetos capturados. Em armadilha de Shannon o horário de maior atividade das espécies prevalentes foi entre 19 e 22 h. Em isca humana Aedes scapularis teve maior densidade das 20 às 21 h, enquanto Mansonia humeralis e Anopheles albitarsis prevaleceram das 18 às 19 h. Dentre as espécies prevalentes em armadilha de Shannon, Coquillettidia shannoni, Mansonia humeralis e Anopheles albitarsis tiveram pico de atividade no mês de abril, Anopheles triannulatus em janeiro e Aedes scapularis em fevereiro.<br>Mosquito catches were made in Guaíra county, Paraná State, southern Brazil, in the vicinity of Itaipu dam, from January to December 1991. The catches were made with a Shannon light trap and human bait. The Shannon light trap was installed beside the highway that used, formerly, to lead to the Sete Quedas cataracts and the human bait was used in the urban area. Data about the Culicidae fauna were obtained as to predominant species, seasonal variation, time of highest density and affinity with human host. Forty-one species were identified as belonging to the Anopheles, Aedes, Aedomyia, Coquillettidia, Culex, Mansonia, Psorophora and Uranotaenia genera. With the Shannon light trap 21,280 mosquitoes were caught and with human bait 1,010. In the catches made with the Shannon light trap, Coquillettidia shannoni, Mansonia humeralis, Anopheles trianulatus, Aedes scapularis and Anopheles albitarsis accounted for 82.78% of all mosquitoes taken. In the catches made on human bait the highest densities of these mosquitoes occurred between 7 p.m. and 9 p.m. Aedes scapularis, Mansonia humeralis and Anopheles albitarsis represented 91,21% of all mosquitoes caugth with human bait. The highest densities of Aedes scapularis, on human bait, were found between 8 p.m. and 9 p.m. and those of Mansonia humeralis and Anopheles albitarsis between 6 p.m. and 7 p.m. Among the genera caught with the Shannon ligth trap Coquillettidia shannoni, Mansonia humeralis and Anopheles albitarsis were most frequent in April, Anopheles triannulatus in January and Aedes scapularis in February