(E4,Z9)-tetradecadienal, a sex pheromone for three North American moth species in the genus Saturnia

The Iepidopteran genus Saturnia has three representatives in North America, S. walterorum, S.mendocino, and S. albofasciata. (E4,Z9)-Tetradecadienal ( E4,Z9-14 : Ald) was identified as a sex pheromone component for all three s pecies by combinations of coupled gas chromatography-electroantennogram det ection (GC-EAD), GC-mass spectrometry (MS), and field trials. In field tria ls, all three species were strongly attracted to (E4,Z9-14 : Ald) as a sing le component. Small amounts of (Z)-9-tetradecenal (Z9-14: Ald) also were fo und in extracts of all three species, but blends of this compound with E4,Z 9-14 : Aid were no more attractive to male moths than E4,Z9-14 : Aid alone. Extracts of pheromone glands of female S. walterorum occasionally containe d a third, trace compound eliciting responses from male antennae in GC-EAD experiments, but this compound was not identified. It is suggested that the three species can use the same, single component as a sex attractant becau se the flight period of S. albofasciata (Fall) is different than that of th e other two species (spring), whereas the geographic distributions of S. me ndocino and S. walterorum overlap over only small portions of their ranges. Furthermore, the latter two species readily hybridize, so there may be min imal fitness cost to cross-attraction.