Silverfish Life Stages
Silverfish are one of the oldest insect orders — over 400 million years old. Unlike most insects, they continue to molt throughout their adult life (up to 60 times). Their presence indicates humidity problems.
Egg
1mm, white, oval. Laid in crevices, paper products, or wall gaps. Female lays 1-3 per day (up to 100 per year). Eggs are difficult to spot — coated in sticky substance that collects debris.
Early Nymph
Hatch white, scale-free. Scales develop by 3rd molt. Require high humidity (70-90%) to survive. Growth is slow — heavily dependent on temperature. May take 3-5 years to reach adulthood.
Late Nymph
Developing silver scales, two antennae, three tail filaments. Now eating starchy materials. Found in bathrooms, laundry rooms, basements. Molts up to 8 times before adulthood.
Adult Silverfish
12-20mm, metallic silver, teardrop-shaped body, three long tail filaments. Moves in a fish-like wiggling motion. Thrives in 70-90% humidity. Can live 2-8 years and continues to molt as an adult.
Firebrat
Similar to silverfish but mottled gray-brown, prefers heat (90-105F). Found near boilers, ovens, and hot water pipes. Slightly faster than silverfish. Often confused at first glance.
Feeding Signs
Irregular surface etchings on paper and cardboard. Yellow stains on fabric. Holes in wallpaper with a peppered appearance. Shed scales near damage sites. Fecal pellets — tiny black specks resembling ground pepper.
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