Blister Beetle (Lytta aenea)
Detailing the physical features, habits, territorial reach and other identifying qualities of the Blister Beetle.
Updated: 2/8/2018; Authored By Staff Writer; Content ©www.InsectIdentification.org
Touching a Blister Beetle can leave its handler with a swollen, painful reminder that some insects are better objects for observation.
Blister Beetles are members of the family Melodiae. If squeezed, they eject a chemical toxin called cantharidin that is a skin irritant to humans. Tissue that comes into contact with this irritant swells into a painful blister. This substance's effectiveness at destroying skin tissue is proven by its use as an ingredient in some wart removal products. It is primarily used as a defense mechanism against predators, but the beetle will use it even when under a perceived threat.
This species of Blister Beetle has a black body and bright red legs. Its 'knee caps' and 'feet' are black. The head is slightly larger than the prothorax (shoulders), but the abdomen is the largest and longest part of the body. Segmented antennae are relatively short and ridged. Black wing coverings fold over delicate wings and look almost like armor plates.
Adult Blister Beetles can be found on apple trees and other similar plants. The larvae are parasites to solitary bees like the Augochlora Sweat Bee. Larvae jump onto a passing bee, stowaway to the bee's lair, and then feed on bee eggs and bee larvae inside. After the Blister Beetle pupates, it makes its way out of the lair.