:''The
striped bark scorpion
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 medi ...
and the closely related
Baja California bark scorpion are also called bark scorpions.''
The Arizona bark scorpion (''Centruroides sculpturatus'', once included in ''
Centruroides exilicauda'') is a small light brown
scorpion common to the
Sonoran Desert in the
southwestern United States
The Southwestern United States, also known as the American Southwest or simply the Southwest, is a geographic and cultural region of the United States that generally includes Arizona, New Mexico, and adjacent portions of California, Colorado, Ne ...
and northwestern Mexico. An adult male can reach 8 cm in length (3.14 inches), while a female is slightly smaller, with a maximum length of 7 cm (2.75 inches).
Predators
Arizona bark scorpions are eaten by a wide variety of animals such as
pallid bats,
birds (especially
owls),
reptile
Reptiles, as most commonly defined are the animals in the class Reptilia ( ), a paraphyletic grouping comprising all sauropsids except birds. Living reptiles comprise turtles, crocodilians, squamates (lizards and snakes) and rhynchocephalians ( ...
s, and other vertebrates. Some examples include
spiders,
snakes,
peccaries,
rodents, and other scorpions. Development, pesticides and collecting scorpions for research or the pet trade also reduces the bark scorpion population.
The painful and potentially deadly venom of Arizona bark scorpions has little effect on
grasshopper mice. Scientists have found the scorpion toxin acts as an analgesic rather than a pain stimulant in grasshopper mice.
Life cycle

Arizona bark scorpions have a gestation period of several months, are born live, and are gently guided onto their mother's back. The female usually gives birth to anywhere from 25 to 35 young. These remain with their mother until their first molt, which can be up to 3 weeks after birth. Arizona bark scorpions have a life expectancy of about 6 years.
Arizona bark scorpions, like most other scorpions, are incredibly resilient. During US nuclear testing, scorpions, along with cockroaches and
lizard
Lizards are a widespread group of squamate reptiles, with over 7,000 species, ranging across all continents except Antarctica, as well as most oceanic island chains. The group is paraphyletic since it excludes the snakes and Amphisbaenia alt ...
s, were found near ground zero with no recorded adverse effects.
Habitat
The Arizona bark scorpion is
nocturnal
Nocturnality is an animal behavior characterized by being active during the night and sleeping during the day. The common adjective is "nocturnal", versus diurnal meaning the opposite.
Nocturnal creatures generally have highly developed sens ...
,
and particularly well adapted to the desert: layers of wax on its exoskeleton make it resistant to water loss. Nevertheless, Arizona bark scorpions hide during the heat of the day, typically under rocks, wood piles, or tree bark. Arizona bark scorpions do not burrow, and are commonly found in homes, requiring only 1/16 of an inch for entry.
Arizona bark scorpions prefer
riparian areas with
mesquite,
cottonwood, and
sycamore groves, all of which have sufficient moisture and humidity to support insects and other prey species. The popularity of irrigated lawns, and other systems which increase environmental humidity in residential areas, has led to a massive increase in the number of these animals in some areas.
''Centruroides'' scorpions are unusual in that they are the only genus in the Southwest that can climb walls, trees, and other objects with a sufficiently rough surface. Arizona bark scorpions practice
negative geotaxis, preferring an upside down orientation, which often results in people being stung due to the scorpion being on the underside of an object.
[
]
The Arizona bark scorpion preys on small and medium-sized animals such as beetles, spiders, crickets, cockroaches, other insects and other scorpions.
The range of the Arizona bark scorpion is from southern
California, southern
Arizona and western
New Mexico. They are also found in
Baja California,
Sonora
Sonora (), officially Estado Libre y Soberano de Sonora ( en, Free and Sovereign State of Sonora), is one of the 31 states which, along with Mexico City, comprise the Administrative divisions of Mexico, Federal Entities of Mexico. The state is d ...
and
Chihuahua Chihuahua may refer to:
Places
*Chihuahua (state), a Mexican state
**Chihuahua (dog), a breed of dog named after the state
**Chihuahua cheese, a type of cheese originating in the state
**Chihuahua City, the capital city of the state
**Chihuahua Mun ...
,
Mexico.
Venom
The Arizona bark scorpion is the most
venomous scorpion in North America, and its venom can cause severe pain (coupled with numbness, tingling, and vomiting) in adult humans, typically lasting between 24 and 72 hours.
Temporary dysfunction in the area stung is common; e.g. a hand or possibly arm can be immobilized or experience convulsions. It also may cause loss of breath for a short time. Due to the extreme pain induced, many victims describe sensations of electrical jolts after
envenomation. Two recorded fatalities have occurred in the state of
Arizona since 1968; the number of victims stung each year in Arizona and
New Mexico is estimated to be in the thousands.
Antivenom
An
antivenin was developed for this species at
Arizona State University
Arizona State University (Arizona State or ASU) is a public research university in the Phoenix metropolitan area. Founded in 1885 by the 13th Arizona Territorial Legislature, ASU is one of the largest public universities by enrollment in the ...
by Dr. Herbert L. Stahnke, and produced in quantities sufficient to treat individuals within the state of
Arizona. This antivenin was not FDA approved, but use within the state of Arizona was allowable and very successful in shortening the duration of symptoms and hospitalization. Production of this antivenin ceased by 2000 and the product was unavailable by 2004. A Mexican-produced antivenin, Anascorp
2, Laboratorios Silanes, Instituto Bioclon SA de CV">ntivenin Centruroides (scorpion) F(ab′)2, Laboratorios Silanes, Instituto Bioclon SA de CV received FDA approval on August 3, 2011, and is now in use.
First aid
Basic first aid measures can be used to help mediate Arizona bark scorpion stings:
* Clean sting site with soap and water
* Apply a cool compress (cool cloth)
* Take acetaminophen (
paracetamol
Paracetamol, also known as acetaminophen, is a medication used to treat fever and mild to moderate pain. Common brand names include Tylenol and Panadol.
At a standard dose, paracetamol only slightly decreases body temperature; it is inferior ...
) or
ibuprofen
Ibuprofen is a nonsteroidal anti-inflammatory drug (NSAID) that is used for treating pain, fever, and inflammation. This includes painful menstrual periods, migraines, and rheumatoid arthritis. It may also be used to close a patent ductus arte ...
for local pain and swelling
Medical emergencies
Arizona poison control centers suggest immediate medical attention if severe symptoms occur, particularly in young children.
The Poison Center may be reached at 1-800-222-1222.
UV lighting

Arizona bark scorpions, like most other scorpions, will glow when exposed to a
blacklight. This is particularly useful in scorpion detection, since Arizona bark scorpions are active during the night, and can be easily spotted using this method. Typical UV
LED
A light-emitting diode (LED) is a semiconductor Electronics, device that Light#Light sources, emits light when Electric current, current flows through it. Electrons in the semiconductor recombine with electron holes, releasing energy i ...
flashlights enable their human operator to readily detect Arizona bark scorpions at a distance of approximately six feet. Newly molted Arizona bark scorpions will not glow under
ultraviolet light for a few days after molting.
Control and prevention
Arizona bark scorpions are tan or light beige tone in color and very small, making them difficult to detect especially on natural terrain (rocky land, multiple vegetation and soil textured land). They are not known to seek out people, but look for places to hide unless provoked or defending their young. Several methods of control have historically been used to control Arizona bark scorpions, such as physical barriers (scorpions are unable to climb smooth surfaces), pesticides,
glue boards, and removing any scorpion congregation areas in the vicinity of the building.
References
External links
*
Further information on the scorpion
{{Taxonbar, from=Q666300
Buthidae
Scorpion, Arizona Bark
Scorpions of North America
Animals described in 1863