Its sting can cause intense pain and neurologic symptoms, and severe reactions occur most often in young children. In the US, call Poison Control at 1-800-222-1222 after a suspected sting; use emergency services for breathing difficulty, collapse, seizure or severe weakness.
We identify, we don't diagnose. If you've been bitten or stung and symptoms develop, or you're worried, seek medical attention.
Size50–80 mm including the tail
MarkingsSmall and slender — light tan to yellowish, not dark · Very thin pincers, more like tweezers than crab claws
WhereArizona and neighbouring states. Shelters under bark, rocks and in block walls, and comes indoors readily.
SeasonMost active on warm nights, spring through autumn
How to tell it apart
Small and slender — light tan to yellowish, not dark
Very thin pincers, more like tweezers than crab claws
Slim tail held to one side when at rest
Climbs well and is often found on walls and ceilings, not just the floor
Glows blue-green under a UV torch, like all scorpions
How it behaves
It climbs very well, which is why it turns up on walls, in ceilings and inside shoes and bedding rather than only under rocks. It is nocturnal and hides in the day in cracks, under bark, and in block walls. Like all scorpions it fluoresces blue-green under ultraviolet light, and a UV torch at night is by far the most effective way to find out whether you have them around the house.
What a bite looks like
There is often little to see — sometimes no mark at all, sometimes slight redness and swelling. The absence of a visible wound does not mean the sting was minor.
Immediate, intense burning pain, often with numbness or tingling that spreads. In more severe cases, particularly in children, there can be muscle twitching, difficulty swallowing, blurred vision and agitation.
We identify, we don't diagnose. In the US, call Poison Control at 1-800-222-1222 for case-specific guidance after a suspected sting. Call emergency services for difficulty breathing, collapse, seizure or severe weakness.
A skin mark cannot confirm which animal caused it. Read the bug bite and sting guide for the limits and the symptoms that should end an online search.
You’ve found one indoors
Shake out shoes, clothing and bedding, and do not walk barefoot at night in areas where they occur. Sealing gaps and fitting door sweeps helps, since they can pass through remarkably narrow openings. A UV torch will show you very quickly whether you have a population.
Common questions
How dangerous is an Arizona bark scorpion sting?
It is the US scorpion of greatest medical concern. Many stings cause local pain and tingling, while severe neurologic symptoms occur most often in young children. Poison Control can assess the specific case; antivenom is used in hospitals for severe envenomation.
Why do scorpions glow under UV light?
A substance in the cuticle fluoresces under ultraviolet. Nobody is certain why it evolved, but it makes a UV torch the single most useful tool for finding them at night.
How do I tell it from a striped bark scorpion?
The Arizona bark scorpion is plain light tan with very slender pincers and no bold stripes. The striped bark scorpion has two dark lengthwise stripes down the back. Range helps too: if you are in Texas rather than Arizona, the striped is far more likely.
Mud · CC-BY