FEMALE SEX-PHEROMONE IN KORSCHELTELLUS-GRACILIS (GROTE) (LEPIDOPTERA,HEPIALIDAE)

In laboratory wind tunnel studies, quiescent Korscheltellus gracilis ( Grote) females initiated wing fanning as light intensity was reduced t o 25-11 lx at the end of a 16-h, 450-lx photophase. Males downwind of a wing-fanning female initiated wing fanning, rapid walking, or both, and upwind flight toward the female typically ensued shortly thereafte r. Wing-fanning females whose abdomens had been removed, and excised h ind wings of females evoked the same male responses, but females whose hind wings had been removed evoked no male response. The sex pheromon e of K. gracilis evidently is released from the female's hind wings, a so far unique site of pheromone release in female Lepidoptera. The im portance of this finding to understanding the mating system of hepiali ds and the ancestral form of pheromone release among the Lepidoptera i s considered.