Categories
Insects

Blister Beetles

Spring in the Sonoran Desert is a good time for the emergence of blister beetles. In past years, I’ve seen swarms of the species Lytta magister, Master Blister Beetle. These are large colorful blister beetles that can be very abundant locally. Yesterday at Highway Tank, I saw for the first time the Iron Cross Blister Beetle, Tegrodera aloga. Also a large species, they are very colorful and a good example of aposematism, or advertising to potential predators that an organism is not worth eating. Aposematic signals are beneficial for both predator and prey, since both avoid potential harm.

The Iron Cross Blister Beetle. These beetles secret cantharidin, a potent toxin that causes severe blistering. The toxin can be lethal if ingested. It is a problem for farmers in some areas. The beetles get into hay and when eaten by horses, the toxin can kill them. On the beneficial side, cantharidin is used in the medical field as a topical medication in the removal of warts, removal of tattoos, and has been researched for certain cancer treatments.
From what I’ve gathered reading about these beetles, they are usually found locally but abundantly, and only for a short time. That is what I saw at Highway Tank. There were hundreds of them but only in a small area.
This is the other species that is more commonly seen: Lytta magister, Master Blister Beetle. Apparently, this species is also toxic. I cannot find any information on whether one or the other is the more toxic. Also a good example of aposematism, but not as pronounced, so maybe this species is not as toxic as the Iron Cross Blister Beetle.

3 replies on “Blister Beetles”

Great shots. I have only seen singles of the Iron Cross. A congregation of them would be fun to see.

Comments are closed.