Trans-bergamotenes-male pheromone of the ectoparasitoid Melittobia digitata.

The first male-produced sex attractant pheromone in the parasitic Hymenoptera has been identified. The elaborate courtship behavior of Melittobia digitata, an idiobiont that parasitizes the last larval instar or the pupal stage of solitary bees and wasps, involves a series of coordinated movements of legs, wings, and antennae, initiated after the female is attracted to the blind, flightless male. We identified alpha- and beta-trans-bergamotene as the active compounds of the male M. digitata sex attractant. Variation in the release of the sex pheromone by males and the pheromone load during aging is also described.