:''The
striped bark scorpion and the closely related
Baja California bark scorpion are also called bark scorpions.''
The Arizona bark scorpion (''Centruroides sculpturatus'', once included in ''
Centruroides exilicauda
''Centruroides exilicauda'', the Baja California bark scorpion, is a species of bark scorpion found in Baja California. It is closely related to the Arizona bark scorpion (''Centruroides sculpturatus''), but is not considered dangerous. Previous ...
'') is a small light brown
scorpion
Scorpions are predatory arachnids of the order Scorpiones. They have eight legs, and are easily recognized by a pair of grasping pincers and a narrow, segmented tail, often carried in a characteristic forward curve over the back and always endi ...
common to the
Sonoran Desert
The Sonoran Desert ( es, Desierto de Sonora) is a desert in North America and ecoregion that covers the northwestern Mexican states of Sonora, Baja California, and Baja California Sur, as well as part of the southwestern United States (in Arizon ...
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, N ...
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,
bird
Birds are a group of warm-blooded vertebrates constituting the class Aves (), characterised by feathers, toothless beaked jaws, the laying of hard-shelled eggs, a high metabolic rate, a four-chambered heart, and a strong yet lightweig ...
s (especially
owl
Owls are birds from the order Strigiformes (), which includes over 200 species of mostly solitary and nocturnal birds of prey typified by an upright stance, a large, broad head, binocular vision, binaural hearing, sharp talons, and feathers a ...
s),
reptiles, and other vertebrates. Some examples include
spider
Spiders (order Araneae) are air-breathing arthropods that have eight legs, chelicerae with fangs generally able to inject venom, and spinnerets that extrude silk. They are the largest order of arachnids and rank seventh in total species d ...
s,
snake
Snakes are elongated, limbless, carnivorous reptiles of the suborder Serpentes . Like all other squamates, snakes are ectothermic, amniote vertebrates covered in overlapping scales. Many species of snakes have skulls with several more j ...
s,
peccaries
A peccary (also javelina or skunk pig) is a medium-sized, pig-like hoofed mammal of the family Tayassuidae (New World pigs). They are found throughout Central and South America, Trinidad in the Caribbean, and in the southwestern area of No ...
,
rodent
Rodents (from Latin , 'to gnaw') are mammals of the Order (biology), order Rodentia (), which are characterized by a single pair of continuously growing incisors in each of the upper and lower jaws. About 40% of all mammal species are roden ...
s, 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
Grasshopper mice are rodents of the genus ''Onychomys'', occurring in North America. They feed on insects and other arthropods.
Biology
The three species in this genus of New World mice are only distantly related to the common house mouse, ''M ...
. 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 al ...
s, were found near ground zero with no recorded adverse effects.
Habitat
The Arizona bark scorpion is
nocturnal
Nocturnality is an ethology, animal behavior characterized by being active during the night and sleeping during the day. The common adjective is "nocturnal", versus diurnality, diurnal meaning the opposite.
Nocturnal creatures generally have ...
,
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
A riparian zone or riparian area is the interface between land and a river or stream. Riparian is also the proper nomenclature for one of the terrestrial biomes of the Earth. Plant habitats and communities along the river margins and banks a ...
areas with
mesquite
Mesquite is a common name for several plants in the genus '' Prosopis'', which contains over 40 species of small leguminous trees. They are native to dry areas in the Americas.
They have extremely long roots to seek water from very far under g ...
,
cottonwood, and
sycamore
Sycamore is a name which has been applied to several types of trees, but with somewhat similar leaf forms. The name derives from the ancient Greek ' (''sūkomoros'') meaning "fig-mulberry".
Species of trees known as sycamore:
* '' Acer pseudoplat ...
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
Gravitaxis (or ''geotaxis'') is a form of taxis characterized by the directional movement of an organism in response to gravity. Gravitaxis is one of the many forms of taxis. It is characterized by the movement of an organism in response to gravit ...
, 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
California is a state in the Western United States, located along the Pacific Coast. With nearly 39.2million residents across a total area of approximately , it is the most populous U.S. state and the 3rd largest by area. It is also the ...
, southern
Arizona
Arizona ( ; nv, Hoozdo Hahoodzo ; ood, Alĭ ṣonak ) is a U.S. state, state in the Southwestern United States. It is the list of U.S. states and territories by area, 6th largest and the list of U.S. states and territories by population, 14 ...
and western
New Mexico
)
, population_demonym = New Mexican ( es, Neomexicano, Neomejicano, Nuevo Mexicano)
, seat = Santa Fe, New Mexico, Santa Fe
, LargestCity = Albuquerque, New Mexico, Albuquerque
, LargestMetro = Albuquerque metropolitan area, Tiguex
, Offi ...
. They are also found in
Baja California
Baja California (; 'Lower California'), officially the Free and Sovereign State of Baja California ( es, Estado Libre y Soberano de Baja California), is a state in Mexico. It is the northernmost and westernmost of the 32 federal entities of Mex ...
,
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 Federal Entities of Mexico. The state is divided into 72 municipalities; the ...
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
Mexico ( Spanish: México), officially the United Mexican States, is a country in the southern portion of North America. It is bordered to the north by the United States; to the south and west by the Pacific Ocean; to the southeast by Guate ...
.
Venom
The Arizona bark scorpion is the most
venomous
Venom or zootoxin is a type of toxin produced by an animal that is actively delivered through a wound by means of a bite, sting, or similar action. The toxin is delivered through a specially evolved ''venom apparatus'', such as fangs or a ...
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
Envenomation is the process by which venom is injected by the bite or sting of a venomous animal.
Many kinds of animals, including mammals (e.g., the northern short-tailed shrew, ''Blarina brevicauda''), reptiles (e.g., the king cobra), spide ...
. Two recorded fatalities have occurred in the state of
Arizona
Arizona ( ; nv, Hoozdo Hahoodzo ; ood, Alĭ ṣonak ) is a U.S. state, state in the Southwestern United States. It is the list of U.S. states and territories by area, 6th largest and the list of U.S. states and territories by population, 14 ...
since 1968; the number of victims stung each year in Arizona and
New Mexico
)
, population_demonym = New Mexican ( es, Neomexicano, Neomejicano, Nuevo Mexicano)
, seat = Santa Fe, New Mexico, Santa Fe
, LargestCity = Albuquerque, New Mexico, Albuquerque
, LargestMetro = Albuquerque metropolitan area, Tiguex
, Offi ...
is estimated to be in the thousands.
Antivenom
An
antivenin
Antivenom, also known as antivenin, venom antiserum, and antivenom immunoglobulin, is a specific treatment for envenomation. It is composed of antibodies and used to treat certain venomous bites and stings. Antivenoms are recommended only if t ...
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 t ...
by Dr. Herbert L. Stahnke, and produced in quantities sufficient to treat individuals within the state of
Arizona
Arizona ( ; nv, Hoozdo Hahoodzo ; ood, Alĭ ṣonak ) is a U.S. state, state in the Southwestern United States. It is the list of U.S. states and territories by area, 6th largest and the list of U.S. states and territories by population, 14 ...
. 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 inferi ...
) 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 ...
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
A blacklight, also called a UV-A light, Wood's lamp, or ultraviolet light, is a lamp that emits long-wave ( UV-A) ultraviolet light and very little visible light. One type of lamp has a violet filter material, either on the bulb or in a sepa ...
. 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 device that emits light when current flows through it. Electrons in the semiconductor recombine with electron holes, releasing energy in the form of photons. The color of the light (cor ...
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
Ultraviolet (UV) is a form of electromagnetic radiation with wavelength from 10 nm (with a corresponding frequency around 30 PHz) to 400 nm (750 THz), shorter than that of visible light, but longer than X-rays. UV radiati ...
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