Transfer of cantharidin (1) during copulation from the adult male to the femaleLytta vesicatoria (‘Spanish flies’)

Summary

Adult males of the ‘spanish fly’Lytta vesicatoria (Meloidae, Coleoptera) are able to biosynthesize cantharidin (1) ‘in copula’ after injection of E, E-11′-(³H,¹⁴C)-farnesol and 2-¹⁴C-methylfarnesoate. During mating, the cantharidin biosynthesized in the males is transferred to the females, who are unable to biosynthesize cantharidin from any terpenoid precursors. After injection of (³H,¹⁴C)-cantharidin into males during copulation, more than 10% is transferred into the female sex organs. Males injected with 2-(³H,¹⁴C)-mevalonate 24–30 h prior to copulation transferred 93–98% of the biosynthesized cantharidin to the females during mating. After mating, the males continue to produce cantharidin. It seems that in the male the biosynthesis of cantharidin is stimulated during copulation.