They really are.
Blister beetles are beetles of the family Meloidae. They cause blisters by ejecting an irritating agent known as cantharidin, which is also used to remove warts (who knew?).
They are hard to photograph because they never stop moving and you can’t really grab them and put them on a leaf (because then you’d suffer from the blisters all over your hands). I can’t remember where I read it, but I once heard that a famous entomologist wanted to know what species of beetle it was and carried one home in his mouth. (Really? I don’t know.)
The compound they use to cause blisters actually is part of their hemolymph, which means that in order to defend themselves, they use “reflexive bleeding.” Don’t you feel guilty now?