Pseudoscorpions

categories: Fact Sheet Nuisance Pests

revision date: 2025-03-15 08:37

Flattened, oval-shaped pseudoscorpion
Pseudo scorpion
Photo by: Lindsay du Toit

Biology

Pseudoscorpions are flattened, oval-shaped, and related to spiders. Pseudoscorpions are commonly found in houses but also occur outside under loose bark, dead leaves, etc.

Although these tiny creatures (usually in the neighborhood of 1/8 inch long) somewhat resemble true scorpions, they lack a stinging mechanism and are thus harmless. They feed mostly on small insects, and are therefore beneficial.

Pseudoscorpions spin small, disk-shaped, whitish, cocoon-like structures in which they lay eggs, overwinter, or shed their skins. These cocoon-like structures may be found in various locations (floor joists, firewood, etc.) where pseudoscorpions have been present.

Management Options

Use Integrated Pest Management (IPM) for successful pest management.

Non-chemical Management

Select non-chemical management options as your first choice!

  • Avoid stacking firewood indoors.
  • Only bring in the amount of wood you are going to burn at any one time.
  • Examine clothes drying on outdoor clothes lines before bringing them inside as they are sometimes found here as well.

Chemical Management

IMPORTANT: Visit Home and Garden Fact Sheets for more information on using pesticides.

  • None recommended


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