BIOSYSTEMATICS OF THE COTESIA-FLAVIPES COMPLEX (HYMENOPTERA, BRACONIDAE) - INTERSPECIFIC HYBRIDIZATION, SEX-PHEROMONE AND MATING-BEHAVIOR STUDIES

Mating behaviour, sex pheromone attraction and reciprocal breeding of Cotesia flavipes Cameron (Hymenoptera: Braconidae), C. sesamiae (Camer on) and C. chilonis (Matsumura) were studied. These three putative spe cies comprise the Cotesia flavipes complex. Wing fanning and antennal vibration were the initial courtship signals from the males. Antennal stroking by the male was also an important contact signal and a prereq uisite to successful mounting and copulation. Interspecific crosses re vealed that males of C. flavipes exhibited courtship behaviour, and mo unted and copulated with females of C. chilonis and C. sesamiae; the m ales transferred sperm but progeny from these crosses did not include females. Males of C. sesamiae copulated with females of C. chilonis an d the progeny included viable females. The progeny backcrosses of the hybrid females to male parents also included viable females. Sex phero mone experiments were conducted in a Y-tube olfactometer and in large field cages. Males and females of C. flavipes perceived and responded to odours emitted by the opposite sex. There was no significant respon se to odours from conspecific individuals of the same sex in any of th e three species. Pheromone bioassays in field cages using sticky traps baited with live virgin C. flavipes females attracted conspecific mal es.