What it means
The bark scorpion is the scorpion Scottsdale residents mean when they say “we’ve got scorpions.” It is small, slim and pale, a straw-colored animal about the length of a thumb, with thin pincers and a long, thin tail. It hunts at night, hides by day in cracks, stacked wood, block walls and clutter, and, unlike the chunkier desert scorpions, it climbs. That is why it turns up on bedroom ceilings and in bathtubs it cannot climb back out of.
Locals talk about it with a particular mix of nonchalance and vigilance. People who have lived here twenty years will tell you they have never been stung, then shake out their shoes as they say it. Neighbors trade pest-control recommendations like restaurant tips, and summer night walks with an ultraviolet flashlight are a recognized suburban hobby.
The full cast of desert creatures, from javelina to Gila monsters, is in the desert wildlife field guide. This page is about the one animal most newcomers ask about first.
Where you’ll meet it
In homes, in garages and pool areas, in block walls, and in the monsoon months, which state health officials have called scorpion season. Real estate conversations and the first-year guide bring it up too.
Where the word came from
The scientific name is Centruroides sculpturatus. The common name, Arizona bark scorpion, is standard in science, medicine and pest control, though nobody has documented who first used it. Locals mostly drop the qualifier and just say scorpion.
What sets it apart is its venom. Arizona has more than 56 scorpion species, according to the state health department, and only the bark scorpion is of public health significance. University of Arizona extension specialists describe it as the most venomous scorpion in the United States, the only Arizona scorpion with a strong tendency to climb, and the only social scorpion found in urban areas, where groups shelter together in hollow-block walls for protection and moisture.
Those habits explain why it lives with people. Houses offer shade, water, insects to eat and walls to hide in. A Banner poison center study the state health department cited in 2011 found that a third of stings happened in bedrooms, about a quarter in living rooms and 6 percent in bathrooms.
What it is not
Not every scorpion in the yard is a bark scorpion. Larger, stockier ground-dwelling species look more alarming, but by the state’s account none of them is of public health significance. And a bark scorpion is not a desert-only problem: the sting data point to bedrooms and living rooms, which is why the standard precautions are about beds, shoes and towels.
The fine print
The numbers are large and mostly reassuring. Arizona’s two poison centers handled almost 5,500 scorpion stings in 2021, and the health department once reported more than 10,000 in a single year. Most need no hospital care. A sting is very painful, numbness and tingling can last several days, and washing, a cool compress and over-the-counter pain relief handle the typical case.
The exception is small children. The health department has estimated that about 200 Arizona children a year need intensive treatment, and the warning signs are specific: difficulty breathing, uncontrolled jerking, drooling and wild eye movements. University of Arizona specialists add older adults and people with high blood pressure to the higher-risk list. The poison centers, reachable at 1-800-222-1222 at any hour, triage calls and tell callers whether to go in.
Treatment improved in 2011. On August 3 the FDA approved Anascorp, an antivenom produced in Mexico and tested in clinical trials run through the University of Arizona, the first drug approved specifically for scorpion stings.
Control is about habitat more than spray. University of Arizona Extension says scorpions cannot be managed with pesticides alone and recommends sealing and caulking the house, replacing worn door sweeps and clearing clutter away from the walls. A UV flashlight at night finds them, since they glow green. Indoors, the state health department advises moving cribs away from walls and removing crib skirts that reach the floor.