Studies on mosquitoes (Diptera: Culicidae) and anthropic environment: 8- Survey of adult behaviour of Spissipes Section species of Culex (Melanoconion) in South-Eastern Brazil

Relatam-se os resultados obtidos mediante a coleta regular de adultos representantes da Seção Spissipes de Culex (Melanoconion) realizada em ambiente antrópico do Vale do Ribeira, SP, Brasil, no período de agosto de 1992 a dezembro de 1993. Foi possível evidenciar a dominância de Culex ribeirensis e de Cx. sacchettae se bem que, no total, tenham sido identificadas dez espécies desse grupo. Esses dois mosquitos revelaram clara tendência a freqüentar as casas onde foram coletados, tanto no intra como no peridomicílio, mediante o emprego da isca humana. No ambiente extradomiciliar, ao que parece, as matas residuais desempenhariam o papel de concentração dessas populações, de onde os adultos sairiam para o terreno aberto cultivado e alcançariam as moradias. Como a competência vetora dessas espécies tem sido revelada mediante o isolamento de vírus em condições naturais, é de se recomendar que mereça atenção devida, a presença desses mosquitos no ambiente artificial humano.A study of Spissipes Section of Culex (Melanoconion) adults behaviour was carried out from August 1992 through December 1993 in human dominated (anthropic) environment in the Ribeira Valley, S.Paulo State, Brazil. By sampling at several sites it the dominance of Culex ribeirensis and Cx. sacchettae became evident even through a total number of ten species was recorded. Those two mosquitoes showed a clear tendency to frequent the domiciliary environment where they were caught, both indoor and outdoor, through the use of the human bait. In the outside environments, the residual patchy forests seems to display a concentration role, from which these adults spread to the open land and reach the dwellings. As their vector competence has been demonstrated through the virus isolations in natural conditions, it is advisable to pay attention to the presence of these mosquitoes in the man-made environment