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Aposematic coloration Means “NO Attempt” – Blister beetles (April 17, 2013)

Spring is the season of blister beetles in desert southwest! Adults are usually found crawling on the ground, hanging on flowers or tree branches. The common name ”Blister beetle” refers to a group of beetle family called “Meloidae”. Adults are herbivores that often seen feeding on pollen or flowers on desert bushes such as creosotes. Larvae are parasitoid or predator which believed to feed on eggs of bees and grasshoppers. Once being attacked or frightened, blister beetles often produce a type of toxic chemical “Cantharidin” that is sometimes poisonous to livestock or human. Especially the genus Epicauta is highly toxic and is occasionally consumed by horses with alfalfa hay, which causes the death of livestock. Unlike most of beetles can be casually handled or touched by hand, blister beetles may not be a fun insect to play with. Toxins excreted from them can be very harmful to human skin, especially those with allergic or sensitive skin. Luckily, blister beetles do not actively attack, toxic chemicals are only produced for defensive mechanism when threatened. So if you encounter those conspicuous little creatures in the wild, DO NOT attempt to grab them without protection!

Aposematic coloration Means “NO Attempt” – Blister beetles

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For questions or comments on any of the topics please contact Marco Pena at the Yuma Agricultural Center.
College of Agriculture, The University of Arizona, Tucson, AZ.

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