OBSERVATIONS ON THE SEXUAL BEHAVIOR OF FREE-FLYING AEDES AEGYPTI MOSQUITOES

¹ Department of Entomology, University of Maryland, College Park, Maryland 20742

1. The sexual behavior of 2 strains of free-flying Aedes aegypti in 1 cu ft cages is described.

2. Groups of resting males are not necessarily activated to flight by flying females under uncrowded conditions, even though the females may fly within 2 inches of them. Individual males tend to be activated to flight if females fly within one inch of them or actually touch them.

3. Flying females do not necessarily elicit directed responses by flying males. When males pursue females, they may fly in one or more loops around them before establishing tarsal contact. Only a small percentage of a male's time is spent in chasing or copulating with females.

4. Copulations taking place in mid-air can be recognized by a sudden change in the flight pattern of the couple from a rapid zigzag to a slower spiralling path. Most couples land before the male makes genital contact with the female. On many occasions males were seen to land beside females and to be in tarsal contact with them. Although some of these males made attempts to clasp stationary females from the side, on only one occasion was a male actually seen to crawl beneath a long-standing female and to copulate with her.

5. Females were never seen to change their stance to facilitate copulatory acts of the males. Although males and/or females may terminate copulation, the lowering of the female's metathoracic legs generally signals an impending end to the act. Females may additionally have to cross their hind legs, stand on their tarsal tips or fly away to dislodge some males.