A defensive steroidal pyrone in the Glow‐worm Lampyris noctiluca L. (Coleoptera: Lampyridae)

Chemical defences against predators appear to be widespread amongst fireflies but, until now, the substances involved have only been identified in a few species, all of them from North America. In the present study, evidence is presented that a similar toxin may be present in a Eurasian species, Lampyris noctiluca L.