Bronze Blister Beetle (Lytta aenea). As I sit, doing research on this beetle, I find my tendency to avoid touching or picking up any critters I encounter as I roam the woods up here to be reinforced. Though some creatures might look innocent or cute and cuddly they can bring on unpleasant consequences. This particular beetle, along with other similar species in the family, Meloidae, numbering in at some 7,500 species, have a defensive secretion of a blistering agent, cantharidin. This substance not only is a blistering agent but is extremely toxic, comparable to cyanide and strychnine. Cantharidin is found in the beetles’ blood and even after its death this substance remains strong and dangerous. Farm animals grazing in fields where Blister Beetles live or have died can be poisoned by eating them. In the case of humans, if actually consumed, as little as 10 milligrams can be fatal.

Cantharidin is an extreme external irritant to people who can end up with very painful swelling and blisters. The cantharidin is so effective in disintegrating a person’s skin that it is used in some wart removal products. There are some very clever flies, bugs and beetles that will eat (alive or dead) Blister Beetles in order to acquire the defensive nature of cantharidin. These insects with the name, cantharidinophilous insects, have become tolerant of the negative effects of this chemical and are better off because of its protection.

Certainly if I don’t know what a creature is, I’m not going to bother it, other than to get a picture of it with a long lens. Definitely not pick it up.