Scorpions are primitive organisms that inhabit a variety of regions throughout the world, and along with spiders, they are among the hundred thousand documented species in the class Arachnida. Around 1,800 scorpion species have been documented worldwide, 25 of which are considered medically harmful. Dozens of scorpion species have been documented as inhabiting the United States, most of which can be found in the southwest, but several species dwell in the southeastern and even midwestern states as well.
The only scorpion species that inflicts medically threatening and potentially deadly stings to humans and pets in the US is Centruroides sculpturatus, or the “Arizona bark scorpion,” which can only be found in Arizona, southeastern California, New Mexico, and far west Texas. At least 20 scorpion species have been documented in Texas, particularly western Texas, and a few scorpion species are notorious for making themselves at home within and around homes in the state. The striped bark scorpion (Centruroides vittatus) is the most commonly encountered scorpion species in Texas, and homes located in all areas of the state are frequently invaded by these stinging pests.
Striped bark scorpions appear similar to all other scorpion species in that they possess the characteristic lobster-like pincers and stinger-equipped tail that is perfectly designed for striking enemies. This species can be recognized for its 2 to 2 ½ inch long body that ranges in color from tan to yellow and features two dark colored stripes running vertically down its back. These scorpions are encountered throughout the year with the exception of the coldest winter months, and they readily invade homes in large numbers to seek refuge from excessive bouts of heat and/or to seek moisture during periods of dry climate. Unlike many scorpion species, striped bark scorpions are capable of climbing walls and they frequently congregate in attics, wall voids, and on the shaded exterior sides of homes.
Striped bark scorpions are not motivated to sting humans unless they become disturbed or are mishandled, but medically significant scorpion sting incidents are frequently reported in the US, especially in Texas. According to data obtained from US poison control centers, Texas follows only Arizona as the state with the greatest number of annual scorpion sting incidents reported to poison control authorities each year. Between 2005 and 2015 an average of nearly 20,000 scorpion envenomation incidents were reported to Texas poison control centers annually, with San Antonio, Dallas and Austin as the most commonly affected areas.
Have you ever sustained a scorpion sting on your property?