Look but don't touch
Blister beetle
When I was a kid just coming into my sexual years, there was a persistent rumor among the boys that a substance called "Spanish Fly" was all you needed to succeed with the girls. Give them some of this mythical stuff and they'd get an itch that only a guy could scratch. It wasn't true, of course, but when I became a naturalist, I learned that the alleged sure-fire ingredient in Spanish Fly is a substance known as Cantharidin, a toxin that can cause blisters. (This doesn't sound too sexy to me.) The compound is secreted for defensive purposes by a group of insects called Blister Beetles. I spotted this member of the beetle family Meloidae on a grass stem from which it surveyed a local field for suitable leaves and flowers. I was not tempted to get too close.