From a total of 12,721 anophelines collected in a lowland
area in Guarai, Rio de Janeiro, from November 1991 to October
1992, 99.7% (12,688) were Anopheles aquasalis. This
species occurred throughout the year, but in higher numbers from April to
September, when rainfall was low or moderate. The proportion of parous
females in June was significantly higher than the annual rate. An.
aquasalis was weakly attracted by a light-trap, and no significant
differences in abundance were detected between nights with and without
moonlight.