The population of immature Mansonia in the white-water floodplain of Marchantaria Island, in Central Amazonia was composed by 74% of Mansonia (M.) humeralis Dyar & Knab, 1916, 14% of Mansonia (M.) titillans (Walker, 1848) and 12% of Mansonia (M.) amazonensis Theobald, 1901, as indicated by frequency of oviposition (egg masses). Number of egg masses of M. humeralis and M. titillans was higher on Pistia stratiotes whereas that of M. amazonensis was higher on Eichhornia crassipes. The total number of larvae and pupae of Mansonia spp. was 6997 and 570, respectively, and was higher in E. crassipes (4372 and 328) than in P. stratiotes (2625 and 242). Most larvae and pupae were found in the season of lowest water-level (August-October), with a peak in August, not being significantly correlated with abiotic factors.
Culicidae; Mansonia; Macrophytes; floodplain; Oviposition