How to Identify Silverfish

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Silverfish normally live outdoors in the soil, but they may occasionally enter homes and buildings in search of food. These insects are known to cause damage to household items such as books, paper products, and clothing. They can also contaminate food and cause allergies. Because they move fast and can hide in tight spaces, silverfish can be quite difficult to catch.


Silverfish are primitive, wingless insects that get their name from their silvery-gray color and their fish-like wiggling motions.

These pests are mostly active at night. During the day, they like to hide in warm, concealed areas with high humidity.

Silverfish can feed on a variety of materials and foods, but they are particularly voracious when it comes to items containing starches, glue, and cellulose (like papers, books, and wallpaper). This makes them a common pest in schools, libraries, and museums.

Size: 1/2″ – 1″ long (13 – 25 mm); about the size of a sunflower seed

Color: Silvery-gray or brown

Shape: Carrot-shaped body with thread-like antennae, 6 short legs, and 3 tail-like appendages

  • 6 short legs
  • Thread-like (filiform) antennae
  • Wide head with small, compound eyes
  • Covered in silvery scales
  • Carrot-shaped body with an elongated abdomen that tapers at the rear
  • 3 long, tail-like appendages (2 cerci and one terminal filament)