I was first introduced to the Blister Beetle in the mid 70's. In a way that I would not wish upon my worst enemy or best friend( in creationist science your best friend is your worst enemy, talk about weird science, lol). Back to the point. I was strolling down the street, was a beautiful summer's eve, when I felt something crawling on the back of my neck. I reached back, gave it a whack and picked it off my neck. First glance I was relieved that it was not a hornet, yellow jacket or bee. I thought only a beetle, good. As I continued my stroll and examination of this unknown beetle, I observed a reddish fluid on the beetle and my fingers. Suddenly, my neck and fingers began to burn, as if a hot comb was pressing against my skin. The back of my neck and fingers blistered something awful but the pain became scientific bliss when I realized that I had my first Blister Beetle.
The beetle in the photo is the Margined Blister Beetle (Epicauta pestifera). Common in the eastern USA. These beetles are vegetarians as adults. The eggs are laid in the soil, upon hatching the instar (nymphs) seek out grasshopper eggs for food. During a drought, when grasshopper eggs are few, they substitute ground nesting bee larva for their food. Some consider them parasitic but they are actually insect predators(insectivores). The blister agent is secreted by the males and given to the females during mating. She puts the fluid on the eggs. This makes the eggs poisonous and repels any creature that finds the eggs. The toxic chemical in the fluid not only burns but it also kills horses, grazing animals and humans when the beetles are eaten. Old timers out there, remember the aphrodisiac "Spanish Fly", well, the ground up beetle was it. Now banned around the world because it is a deadly poison. If you ever wondered what a Spanish Fly looked like, here it is.
