UW Plant Disease Facts


Authors: Phil Pellitteri, UW Insect Diagnostic Lab
Last Revised: 04/27/2004
D-number: XHT1112

Have you ever found a strange, scorpion-like creature in your home? Pseudoscorpions are common, but rarely seen. 

A pseudoscorpion.
A pseudoscorpion.

They are harmless, small (116 to 18 inch long), tick-shaped critters that have a large pair of pincers, but lack the long tail and stinger of a true scorpion. Pseudoscorpions are beneficial, because they feed on carpet beetles, ants, mites, small flies and other critters in the home. They are usually found in small numbers and spend most of their time hunting in closets and other quiet places. They cannot bite. There are a number of species that commonly inhabit leaf litter outdoors, but Cheilfer cancroides is the common indoors species that is found worldwide.

Pseudoscorpions can live for two years or more. They have silk glands that they use to build retreats and cover their eggs. They prefer humid conditions in homes and are often found in or near the bathroom. When cornered, they will often walk backwards and raise their pincers in a threatening posture. If they fall into a sink they may not be able to crawl out. It is unusual to see more than one or two a month in the average home.

Control: Control is neither needed nor suggested. Because pseudoscor­pions eat pest insects in the home, it is better to preserve their numbers. They are harmless to people and pets. If needed, pseudoscorpions can be captured on sticky traps, such as glue boards, and should respond to indoor residual ant and roach sprays.

For more information on pseudoscorpions: Contact your county Extension agent.

This Fact Sheet is also available in PDF format:

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References to pesticide products in this publication are for your convenience and are not an endorsement or criticism of one product over similar products. You are responsible for using pesticides according to the manufacturer’s current label directions. Follow directions exactly to protect the environment and people from pesticide exposure. Failure to do so violates the law.

Thanks to Karen Delahaut and Susan Mahr for reviewing this document.

A complete inventory of UW Plant Disease Facts is available at the University of Wisconsin-Madison Plant Disease Diagnostics Clinic website: https://pddc.wisc.edu.