Many people in the Phoenix area assume that every scorpion they come across is an Arizona bark scorpion. That's not necessarily the case.
Arizona is home to dozens of species of scorpions. While all scorpions have venom that they might use to capture their prey, not all scorpions have venom that is harmful to humans. Here in Arizona we don't have the largest scorpions in the world, and we don't have the deadliest scorpions in the world, but we do have a scorpion with a rather potent venom: the Arizona bark scorpion. At best, a sting from that scorpion can be rather annoying, or, at worst, the scorpion sting can be extremely painful with longer lasting effects. Deaths from scorpion stings are very rare. People who are prone to have allergic reactions to stings, and those with undeveloped or compromised immune systems (the very young and very old), may have strong or severe reactions. Small pets may also have adverse reactions.
The Sonoran Desert covers an area of about 100,000 miles and includes southeastern California, most of Baja California and Baja California Sur, parts of northwestern Mexico including the cities of Guaymas, Hermosillo and Puerto Peñasco (Rocky Point), and much of the southern half of Arizona, including the cities of Tucson, Yuma and Phoenix. In the pages that follow you'll get some tips on how to identify the four most common types of scorpions that we are likely to find in the Sonoran Desert. Of course, they are identified by by their anatomical differences, so here is terminology relating to the anatomy of a scorpion
The information in the pages that follow was provided primarily by Kari J. McWest of Canyon, Texas. He is associated with American Tarantula Society Headquarters, Scorpion Systematics Research Group in the Division of Invertebrate Zoology at the American Museum of Natural History (AMNH) and REVSYS: Systematics of the Scorpion Family Vaejovidae. Looking for other Arizona scorpion species? Here is Mr. McWest's list by state.