A new role for antennation in paper wasps (Hymenoptera, Vespidae): antennal courtship and sex dimorphic glands in antennomeres

Males of Polistes dominulus perform antennal vibrations and grasping of female antennae during pre-copulatory and copulatory phases. Male antennation plays a relevant role in mating success. In several antennomeres of males of P dominulus and Vespa crabro, a further species in which we observed male antennation, we found secretory cells of class I and 3 associated to the same release site. In P dominulus, class 3 cells with ampulla-like reservoirs and class I cells release their secretion through hairless multiporous areas. In V crabro, tyloid-like structures are associated with large apodemes. The as yet unidentified secretion of these glands may act as a contact or low-volatile sex pheromone during courtship behaviour.