The Arizona bark scorpion is a small light brown scorpion common to the Sonoran Desert in southwest United States 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).
Bark scorpions are eaten by a wide variety of animals such as birds (especially owls), reptiles, and other vertebrates. Some examples include spiders, snakes, peccaries, rodents, and other scorpions.
The painful and potentially deadly venom of 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.
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 may live up to 6 years.
The bark scorpion is particularly well adapted to the desert: layers of wax on its exoskeleton make it resistant to water loss. Nevertheless, bark scorpions hide during the heat of the day, typically under rocks, wood piles, or tree bark. 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.
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. 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 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.
Fatalities from scorpion envenomation in the USA are rare and are limited to small animals (including small pets), small children, the elderly, and adults with compromised immune systems.
Extreme reaction to the venom is indicated by numbness, frothing at the mouth, paralysis, and a neuromotor syndrome that may be confused with a seizure and that may make breathing difficult, particularly for small children.
Basic first aid measures can be used to help remediate scorpion stings:
- Clean sting site with soap and water
- Apply a cool compress (cool cloth)
- Take paracetamol or ibuprofen for local pain and swelling
Since the amount of venom a scorpion injects varies, Arizona poison control centers suggest immediate medical attention only in the event of extreme pain or stings involving weaker individuals.
Scorpions are unable to climb smooth surfaces such as glass, ptfe, polished metals. Many place legs of beds, cribs, and furniture in glass jars. Surrounding a structure such as a home with a glass strip barrier eliminates the entry of scorpions completely.
All scorpions including Bark Scorpions are lacking the anatomical feature arolia. Without this the ability to climb smooth surfaces is impossible.