What are silverfish?

Silverfish, Lepisma saccharina, are small, wingless bugs that are characterized by their silvery (or light grey) body colour and fish-like look, hence the name. It is also known as fishmoth.  As you can guess from its scientific name, it feeds on starches and natural sugars.

Silverfish are 13-25 mm long and have two antennae and two tiny eyes that are too small to be seen by the naked eye. Some species are completely eyeless. They possess three long appendages extending from their backs. Newly-hatched silverfish are whiteish, but their colour turns to metallic silver when they get older.

What do silverfish eat?

Silverfish’s diet is composed mainly of carbohydrates, sugars, and starches. They will eat anything from paper, wood, and clothes to glue, coffee, and dead insects.  In huge populations, these bugs are very destructive, feeding on almost anything in a household. Furthermore, they prefer moist and slightly wet conditions. So damp clothing and moist food will be good sites for infestation.

Interesting Silverfish Facts

  • Silverfish can’t cross an area with masking tape. They can’t grip very flat surfaces.
  • Silverfish can live at an average of 2-4 years, but it can live up to 8 years at optimum conditions.
  • Silverfish bugs hate the smell of citrus.
  • The saccharina in Lepisma saccharina stands for “–saccharides” or “carbohydrates”.


Find some silverfish. Put them in a jar with a slice of moist cake or bread. Observe how they infest the cake. Record the time it takes for them to eat halve the cake.