Adult: approx. 12 mm
A full-grown silverfish is around one centimetre long, wingless, silver insect with a body that tapers off at the end. Its antennae are long and filamentous. It has three long hairs at the end of its body. The larva is similar to the adult but smaller in size.
The silverfish lives in damp and warm indoor premises: sewers, kitchens, bathrooms and cellars. It moves around during the night time and escapes quickly when the light is switched on.
A silverfish moves from one space to another through, for example, the entries of pipes, and is also able to crawl into apartments through drain traps. The silverfish lays its eggs into holes and cracks.
It eats materials that are high in starch. It can dissolve cellulose and can therefore eat wallpaper adhesive, glue used for book binding, mouldy paper and even photos. It can also feed on dirty textiles, leather and synthetic materials and chew holes into them.
In bathrooms, the silverfish feed on hair, loose skin cells and dirt. If there are a large number of silverfish, it may be a sign of moisture damage, as silverfish also feeds on mildew mycelium and spores.
At least two annual generations are produced. Silverfish can live for up to five years. They do not like dry, well-ventilated spaces.
Silverfish do not usually cause any visible damage and do not often damage the food stuffs, either. A silverfish can, in theory, spread diseases, when moving from the sewers onto surfaces where food is prepared.
Prevention and extermination
You can decrease the amount of silverfish by pouring boiling water into the sewers. If necessary, you can treat the spots, where water is used daily (such as floor drains and pipes) with a solution including pyrethrin every evening. A more long-term pesticide is used on baseboards and other places, where there are cracks, in which the pesticide can remain for several weeks. After it is no longer effective, the treatment can be carried out again.