Silverfish—Lepisma saccharina & Firebrat—Thermobia domestica
Also called bristletails because of the three long tail-like appendages at the hind end. They live normally outdoors under rocks, bark and leaf mold, but can be a nuisance when they enter homes. Silverfish are most likely found in moist areas such as kitchens, bathrooms and basements. Removing sources of dampness may eliminate the problem. Firebrats live in warmer, humid places such as attics in the summer and near ovens, fireplaces and central heating pipes in winter. They are harmless to humans and pets but can damage papers, wallpaper, books and sometimes clothing. Both insects are nocturnal, and move quickly when caught in the light.
Silverfish adults are slender, wingless insects, about 1/2 inch long, with silvery-metallic scales covering their body and antennae as long as their body.
Firebrats adults are slender, wingless insects, about 1/2 inch long, with tufts of brown scales which give a mottled appearance and antennae which are longer than their body.
Damage caused by silverfish.
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Identification and Control Information
- Integrated Pest Management In and Around the Home: Silverfish and Firebrats (PDF)—University of California Pest Notes
- Integrated Pest Management Fact Sheet Series: Silverfish and Firebrats (PDF)—Minnesota Department of Agriculture
- Community Horticulture Fact Sheet: Silverfish and Firebrats (PDF)—Washington State University Extension
[Photos, left to right: Jeff Hahn, University of Minnesota Extension; Clemson University—USDA Cooperative Extension Slide Series, Bugwood.org]