The striped bark scorpion (Centruroides vittatus) is an extremely common scorpion found throughout the midsection of the United States and northern Mexico. It is perhaps the most frequently encountered scorpion in the U.S.
Appearance
A medium-sized scorpion that is rarely longer than 70 mm (up to around 2 3/4 in), the striped bark scorpion is a uniform pale-yellow scorpion that can be identified by two dark, longitudinal stripes on its carapace, with a dark triangle above the ocular tubercle. Minor variations on this theme occur, however; specimens that are lighter-colored and lack the characteristic stripes have been described as separate species in the past. Their color suits their environment well, providing them with a natural camouflage from predators as well as prey. Males have a pectinal tooth count of 21–30, while females count 20–27.
Distribution and habitat
The natural geographic distribution of C. vittatus is formed by several adjoining South-Central US states and northern Mexico. Beginning in the northern Mexico Border States, Chihuahua, Coahuila, Nuevo León, and Tamaulipas, C. vittatus’s range extends upward longitudinally through Texas, Oklahoma, and Kansas, to reach as far north as Thayer County, Nebraska. The area also extends laterally from the Sangre de Cristo Mountains and Rio Grande in New Mexico and south Colorado to the Missouri and Mississippi Rivers in Missouri and Louisiana. In all, the range includes the following states: Arkansas, Colorado, Kansas, Illinois, Louisiana, Mississippi, Missouri, Nebraska, New Mexico, Oklahoma, Florida, Georgia, and Texas.
Reports have also found C. vittatus in locations inconsistent with the aforementioned natural geographic distribution. Populations seem to be found only in particular cities outside its natural distribution, so it is thought likely that human activity has introduced C. vittatus to these areas. They include locations in Iowa (Harrison County), Kentucky (Marshall and Calloway Counties), Louisiana (East Baton Rouge Parish and Orleans Parish), Mississippi (Lamar, Pike, and Rankin Counties), Missouri (Clark County), North Carolina (Dare, Nash, and Wake Counties), and Tennessee (Rutherford and Shelby Counties). Additional sightings have occurred in Arizona (Maricopa County), California (Contra Costa County), and Colorado (Boulder County).
A wide geographic distribution allows C. vittatus to occupy desert, deciduous and coniferous forest, and temperate grassland [biomes], where they can be found in crevices under rock and surface debris, vegetation, old rural structures like sheds and barns, and houses during the day. At night, this species emerges from its daytime home and can be found on the open ground or in vegetation, like microphyllous desertic brushwood or other classifications.
Behavior
While placement in the genus Centruroides implies this species is a semi-arboreal one, the striped bark scorpion spends a substantial amount of its time on the ground; and can be found under rock and surface debris, within vegetation, and in weathered rural structures such as old sheds and barns during the day. The terrestrial preferences of this species carry into the night hours, when the scorpion emerges from its temporal shelter at or after sunset to forage for potential prey. Juveniles, however, spend a substantial amount of time in vegetation, likely to avoid predation to which they are more vulnerable. C. vittatus has a very dynamic diet which includes insects, smaller arachnids, and juveniles of the same species. It is preyed on by birds, reptiles, some mammals, and larger arachnids.