Silverfish are nocturnal insects typically 13–25 mm (0.5–1.0 in) long. Their abdomens taper at the end, giving them a fish-like appearance. The newly hatched are whitish, but develop a greyish hue and metallic shine as they get older. They have two long cerci and one terminal filament at the tip of the abdomen between the cerci. They also have two small compound eyes, despite other members of Zygentoma being completely eyeless, such as the family Nicoletiidae.
Silverfish are agile runners and can outrun most of their predators (including wandering spiders and centipedes). However, such running is possible only on horizontal surfaces, as they lack any additional appendages, and therefore are not fast enough to climb walls at the same speed. They also avoid light.
Homeowners with homes that are particularly ideal for a silverfish infestation can prevent a problem by changing the conditions where they live.
What’s the lifespan of a silverfish?
The female lays groups of fewer than 60 eggs at once, deposited in small crevices.
When the nymphs hatch, they are whitish in colour and look like smaller adults. Silverfish are among the few types of insects that continue to moult after reaching adulthood.