Blister Beetles (Meloidae)

Blister beetles are beetles of medium or large size, found on flowers, trees, or wandering on the ground, on the slopes, among grasses or along the roadways.

Zonabris geminata. CAMBODGE, 1988.Meloe proscarabaeus. GUINEE, 1998.Meloe violaceus. TCHECOSLOVAQUIE, 1992.

The blood and the genitalia of all representatives of this group contain cantharidin, a substance that causes blistering when it is applied to the skin, and supposed to be an aphrodisiac. When they are disturbed, they have a haemorrhage reflex: they emit blood from the joints of their cuticle.
Below Lytta vesicatoria, or Spanish fly, consumed in powder like aphrodisiac.

Lytta vesicatoria. CAMBODGE, 1994.

Larvae of blister beetles undergo complex and pronounced changes during their life cycle, called hypermetamorphosis.  Some stages of these larvae develop at the expense of Hymenoptera.