Function of secretion of mandibular gland of male in territorial behavior ofXylocopa sulcatipes (Hymenoptera: Anthophoridae).

Males of the carpenter bee,Xylocopa sulcatipes, establish and defend territories which they mark with the secretions of their mandibular glands. Chemical analysis of the glandular blend revealed that it is composed of guaiacol,p-cresol, and vanillin. Territorial males recognize other intruding males either by sight or by the odor emitted from their mandibular glands. They chase the intruder out of the territory immediately, but will not do so if the visitor is a female. If a female, however, is scented with the reconstituted synthetic pheromonal blend and introduced into a territory of a male, it is treated as a male and chased out of the territory. It is suggested that the blend has a dual function: Guaiacol seems to be the aggressiveness elicitor, while vanillin is the territorial marker and female attractant and therefore could be considered a sex pheromone.