Pest profile

Pseudoscorpions

Pseudoscorpiones (e.g., house pseudoscorpion, Chelifer cancroides) · Pseudoscorpiones: Cheliferidae[3]

Pseudoscorpions are tiny arachnids with pincer-like claws that are neither dangerous nor destructive. Homeowners usually find them in bathroom sinks and tubs and often mistake them for ticks or small spiders.[1]

House pseudoscorpion on a white wall, a tiny dark teardrop-shaped arachnid with a ribbed abdomen and long reddish pincer arms
House pseudoscorpion on a white wall, a tiny dark teardrop-shaped arachnid with a ribbed abdomen and long reddish pincer arms. (c) Jason Hill, some rights reserved (CC BY) — via iNaturalist, CC BY 4.0

How to identify it

  • Pseudoscorpions are very small; most have a body under about 1/8 inch, and the house pseudoscorpion is 3 to 4 millimeters long.[2][1]
  • A pair of long pincer arms (pedipalps) in front, like a scorpion's claws, is more than twice as long as the legs in the house pseudoscorpion.[1][2]
  • The body is teardrop-shaped with a segmented abdomen, and the house pseudoscorpion is a rich mahogany color.[1][2]
  • Unlike true scorpions, they have no long tail and no stinger.[2]

Look-alikes

Look-alikeHow to tell them apart
TicksPseudoscorpions are often mistaken for ticks, but their crab-like pincer arms in front, longer than the legs, set them apart.[1]
ScorpionsPseudoscorpions are far smaller and lack the long tail and stinger of a true scorpion.[2]

Where it lives

More than 2,000 species are described, mostly in the tropics; the house pseudoscorpion is found worldwide, Pennsylvania has several dozen species and Texas has 33.[1][2]

Biology and life cycle

They hunt small arthropods, including caterpillars, flies, ants, beetle larvae and booklice.[1][2]

They live in leaf litter, rotting logs, under bark, in caves, in bird and rodent nests, and in homes.[2][1]

A female carries her 20 to 40 eggs beneath her abdomen, and the young may ride on her back for a few days before dispersing.[1]

Young molt three times; development takes 10 to 24 months depending on temperature, and adults can live 3 or 4 years.[1]

They can spin silk, which they use to build nests.[2]

Some ride on beetles or other large insects, where they apparently feed on mites.[2]

Damage and signs

  • They are not destructive and are not considered pests.[1][2]

Health risk

Pseudoscorpions are medically harmless: they have no stinger and pose no hazard to homeowners.[2][1]

Control

Prevention

No treatment is needed; Penn State Extension does not recommend using pesticides against pseudoscorpions.[1]

Sanitation

Finding them may point to high indoor humidity or a population of the small arthropods they eat, which is worth checking.[1]

Common questions

Is a pseudoscorpion a baby scorpion?
No. Pseudoscorpions are their own group of arachnids; they have no tail or stinger and stay tiny as adults.[2][1]
Why do I find pseudoscorpions in the bathroom?
Homeowners commonly discover them in sinks and tubs, and their presence may reflect humid conditions or the small arthropods they feed on.[1]

Sources

  1. Penn State Extension, “Pseudoscorpions (updated June 24, 2026).” extension.psu.edu/pseudoscorpions (accessed 2026-10-06)
  2. Texas A&M AgriLife Extension, “Pseudoscorpion (Field Guide to Common Texas Insects).” texasinsects.tamu.edu/pseudoscorpion/ (accessed 2026-10-06)
  3. iNaturalist, “Chelifer cancroides taxon page (order and family).” www.inaturalist.org/taxa/409775 (accessed 2026-10-06)

Updated 2026-10-06. Built from sourced records. Spot an error? Tell us.