Anopheles mascarensis (De Meillon, 1947), major vector of malaria in Fort-Dauphin (Madagascar).

Anopheles funestus and Anopheles gambiae s.l. have been considered until no w the major vectors of malaria everywhere in Madagascar Anopheles mascarens is, a mosquito native to Madagascar, has been identified in Sainte-Marie is land as a secondary vector only. In 1997, an entomological study was carrie d out to identify the malaria vectors in the area of Fort-Dauphin, South-Ea st of Madagascar: Every month, mosquitoes were collected from landing catch es on human volunteers (from 7:00 am to 5:00 pm inside dwellings and from 7 :00 am to 0:00 pm outside) and from knockdown spray-collections indoors. An . mascarensis was the most abundant mosquito; the average number of An. mas carensis bites per man/night was 7,6. The sporozoite index was 0, 89 %. Des pite the presence of An. funestus and An. gambiae s.l., An, mascarensis was found to be responsible for 2/3 of the infectious bites (25 infectious bit es per man 1 year). An. mascarensis is widely distributed in Madagascar bur only specimens from the east coast have been found to carry sporozoites of human malaria. Further arguments are thus advanced for the hypothesis acco rding to which a sibling species of An. mascarensis is present in Madagasca r.