The evolution of the mating system of the Carpenter bee Xylocopa varipuncta(Hymenoptera: Anthophoridae)

The Carpenter bee, Xylocopa varipuncta , appears to have evolved a dispersed lek mating system. Males leave the natal nest in the late afternoon in March and April to hover for periods of up to two hours in the crowns of non-flowering trees growing in desert washes. Females and other males occasionally visit a hovering male, probably drawn by a sex pheromone. Resident males repel intruders of the same sex and attempt to induce females to alight on foliage, where mating occurs. The hovering territories do not contain nests, or potential nest sites, or food resources for females. Lek territoriality may have evolved in this species because nests are difficult to locate and the food-plants are evenly dispersed over a large area, making economical defence of patches of this resource unfeasible. Males are left with the option of demonstrating social dominance to potential mates through control of a superior landmark territory.