The silverfish (Lepisma saccharinum) is a species of small, primitive,[1] wingless insect in the order Zygentoma (formerly Thysanura). Its common name derives from the insect’s silvery light grey colour, combined with the fish-like appearance of its movements. The scientific name (L. saccharinum) indicates that the silverfish’s diet consists of carbohydrates such as sugar or starches. While the common name silverfish is used throughout the global literature to refer to various species of Zygentoma, the Entomological Society of America restricts use of the term solely for Lepisma saccharinum.[2]

Description

The silverfish is a nocturnal insect typically 13–25 mm (0.5–1.0 in) long.[3] Its abdomen tapers at the end, giving it a fish-like appearance.[4] The newly hatched are whitish, but develop a greyish hue and metallic sheen as they get older.[5] It has two long cerci and one terminal filament at the tip of the abdomen between the cerci. It also has two small compound eyes, although other members of Zygentoma are eyeless, such as the family Nicoletiidae.[4][6]

The silverfish, like other species in Apterygota, is wingless.[4][7] It has long antennae, and moves in a wiggling motion that resembles the movement of a fish.[8] This, coupled with its appearance and silvery scales, inspires its common name. Silverfish can regenerate lost terminal filaments and antennae within four weeks.[9] Silverfish typically live for up to three years.[10]

The silverfish is an agile runner. It avoids light.[11]