Domiciliation of Culex (Melanoconion) mosquitoes in man-made deeply modified environment

Abstract

Some data on Culex (Melanoconion) mosquito behavior in human environments are presented. Adults were collected simultaneously through peridomiciliary and extradomiciliary catches, with the use of human bait inclusive. Dominant species were identified as Cx. delpontei, Cx. ocossa, Cx. ribeirensis, Cx. sacchettae and Cx. taeniopus. In the domiciliary environment Cx. ribeirensis and Cx. sacchettae, the principal species found, were collected with considerables frequency by the use of human bait placed in the peridomiciliar environment. Cx. delpontei and Cx. ocossa showed a lower frequency in that environment. Greater numbers of adults were obtained in the first three months of the year, particularly in March. Nocturnal activities showed two apparently distincts patterns. One of them was presented by Cx. ribeirensis, Cx. sacchettae and Cx. taeniopus as a curve increasing quickly during the first hours os the night and mantaining the same level until dawn. The other was shown by Cx. delpontei and Cx. ocossa, as a curve which increased gradually until midnight, and then decreased gradual by until dawn. Breeding places of Cx. delpontei were found in medium and large rivers with a covering of aquating floating vegetation, mainly Pistia. Considerations relating to those ecological aspects of epidemiological interest are made.