Utetheisa ornatrix courtship

Conner, W. E. Roach, B., Benedict, E., Meinwald, J. and Eisner, T. (1990). Courtship pheromone production and body size as correlates of larval diet in males of the arctiid moth, Utetheisa ornatrix. Journal of Chemical Ecology 16 543-551. 

Figure 12.5 Utetheisa ornatrix. A Male (above) stroking its everted coremata against female during courtship. B Larva feeding on seed pod of its natural, pyrrolizidine alkaloid-containing food plants (Crotalaria spectabilis). C Scanning electronmicrograph of abdominal tip of male, showing coremata in everted (left) and retracted condition. [Bar = 1 mm A and C from Eisner, 1980].

Host plants play a key role in the production and use of sex pheromones by herbivorous insects through larval or adult sequestration of chemically active compounds and pheromone precursors [210]. One of the best examples of sequestration of plant chemicals by larvae and their subsequent use by adult males in sex attraction or courtship interactions is shown in Utetheisa ornatrix (Arctiidae), whose courtship pheromone derives from pyrrolizidine alkaloids (PAs) ingested at the larval stage from the host plant Crotalaria spectabilis [211]. U. omatrix larvae sequester PAs (e.g. monocrotaline) and retain the alkaloids through metamorphosis into the adult stage to provide egg protection for the next generation. 

---