Neopyrochroa flabellata

Behavior

Male pyrochroid beetles seek out blister beetles and ingest the blistering agent (cantharidin) exuded as a defense mechanism by these meloid beetles. (One source I found said the male fire-colored beetles "lick off" the cantharidin. Another said they "feast compulsively on meloid carcasses". Regardless, male pyrochroid beetles consume canthariden.)

The toxic cantharidin deters predators from dining on beetles that have ingested it. Perhaps more importantly, it makes the male pyrochroids more attractive to females. As an introduction to mating, the pyrochroid male secretes a gooey substance from a groove-like structure in his forehead. The female tastes it. Only if she detects cantharidin does she readily agree to mate. Females actively reject advances from males having none of this toxic substance.

During breeding cantharidin is transferred to the female affording her some protection from predators and, more importantly, she passes the chemical defense onto her eggs. Studies using ladybugs as predators have shown the cantharidin reduces egg predation.