Courtship Behavior and Evidence for a Sex Pheromone in the Parasitoid Campoletis sonorensis (Hymenoptera: Ichneumonidae) 1

Abstract

In investigations in Texas, males of Campoletis sonorensis (Cam.) exhibited four main elements of courtship behaviour when exposed to females or odour-laden air from females. These were orientation, wing vibration, antennal touching and attempted copulation. Odour from females lowered the threshold for the behavioural elements. Wing vibration may aid the male in orientating towards the odour source. Actual orientation of the male to another insect appeared to involve sight, while antennal touching was used by the male to position itself with respect to the female. Orientation and attempted copulation with males occurred as readily as with females in the presence of the female pheromone. Both virgin and mated males responded to both virgin and mated females. Multiple-mated older females were less active in eliciting male courtship. No region of the female could be isolated with respect to pheromone production. Ethyl acetate extracts of females were effective in eliciting courtship behaviour of males.