Feeding preferences and domiciliation of Culicidae mosquitoes in the Ribeira Valley, S. Paulo State, Brazil, with particular reference to Aedes scapularis and Culex (Melanoconion)

Abstract

New results on blood-meal identification and the environmental distribution of mosquitoes collected in four different Ribeira Valley (S. Paulo State, Brazil) environments, during the period February to November 1986, are presented. Sources of 651 blood-meals were identified. The preference of Ae. scapularis for large mammals, chiefly cattle, horse and even man, was confirmed. Data suggests that a similar behavioral pattern is presented by Cx. ribeirensis. Both mosquitoes seem to be strongly attracted by peridomiciliar blood sources represented by domestic animals sheltered in that environment. Nevertheless, the female of Ae. scapularis females may use the extradomiciliary environment, represented by residual forests, as resting place in the same way as it uses the peridomiciliary one. The data confirm the clear tendency of both Ae. scapularis and Cx. ribeirensis to adapt to the man-made environment and thus the evolution towards domiciliation in the behavior of these mosquitoes. Other culicids, such as An. bellator, An. cruzii and Cq. chrysonotum, were collected practically only by the use of human bait. For An. cruzii the number of females collected by this method represented 31.6% of the female total collected during this project. Some data about other species are given, and the need for further researches about Culex (Melanoconion) species is emphasized.