Silverfish

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Lepisma saccharina (commonly called the fishmoth, urban silverfish or just the silverfish) is a small, wingless insect typically measuring from half to one inch (12 to 25mm). Its common name derives from the animal's silvery blue color, combined with the fish-like appearance of its movements, while the scientific name indicates the silverfish's diet of carbohydrates such as sugar or starches. It belongs to the basal insect order Thysanura, and the species is estimated to have existed for 300 million years, originating in the Palaeozoic Era.^[1] Often misidentified as a silverfish is the house centipede, another house-dwelling arthropod that exhibits rapid, fluid movement.

An eyeless species of silverfish, or a close relative, was discovered in January 2006 in caves in Sequoia National Park, California.

[edit] Diet

The favourite food of silverfish is any matter that contains starch or polysaccharides, such as dextrin in adhesives. These include glue, book bindings, paper, photos, sugar, hair, and dandruff. Silverfish can also cause damage to books, tapestries, and textiles. Silverfish will commonly graze in and around showers, baths, and sinks on the cellulose present in many shampoos, shaving foams and so on. Apart from these cases, the damage caused by silverfish is negligible and they have no direct effect on human health beyond psychological distress to those who are frightened by their appearance. However, they also have a bite which may cause irritation but has no long term effects. Other substances that may be eaten include cotton, linen, silk and synthetic fibres, and dead insects or even its own exuvia (moulted exoskeleton). During famine, a silverfish may even attack leatherware and synthetic fabrics. In extreme cases, silverfish may live for a year without eating.

[edit] Habitat

The silverfish is a widespread commensal in human dwellings, much like its relative, the firebrat (Thermobia domestica). Silverfish can often be found under refrigerators, beds, or around a well-heated toilet, if the crevices in the floor tiles are large enough. It is also common to find them near the crevices of the wood that has been bonded with starch glue (from which they feed), especially where the wall and floor meet. They are quite shy and most of them come out at night, when there isn't much human activity nearby. Firebrats prefer warmer conditions, and can be found in bakeries, where they feed on flour and bread, as well as other animal products.

[edit] Reproduction

The reproduction of silverfish has only recently been studied. The male lays a spermatophore, a sperm capsule covered in gossamer. Having located the spermatophore via a variety of biochemical signals, the female takes up the spermatophore for fertilization, which will then result in a fertilized egg. ^{[citation needed]}

[edit] Predation

Earwigs, house centipedes, and in rare cases spiders are known to be predatory upon silverfish.

[edit] Elimination

In buildings, silverfish can only exist in sufficiently humid, crevice-rich environments. If these two conditions are removed, the silverfish will not be able to survive. Other measures that may be taken to eliminate silverfish, at least temporarily, include the following:

Non-lethal

• By far the most effective way to be rid of silverfish for sure is to keep an area or room tidy, limiting the possible number of breeding grounds they have.
• Ensuring showers, baths etc. are rinsed clean and free of any residual toiletries that may attract hungry silverfish.
• Leaving the bathroom door open after a shower to lessen the humidity
• The scent of a sal ammoniac solution should drive away silverfish within 24 hours.
• To capture silverfish, trap in small glass containers -- silverfish cannot climb up the smooth inside walls.

Lethal

• Silverfish can also be caught by sprinkling plaster on a wet, white cotton cloth, put it in a corner overnight, near the silverfish's hideout.
• It is important when filling crevices in which silverfish are living or may potentially live to use a filler material which is either toxic to insects, or does not contain materials which would supply the silverfish with a source of food.
• A 1:1-ratio dispersion of borax or boric acid and sugar is a reliable bait to kill silverfish (relatively non-toxic to non-insects).
• Adults can be killed by freezing, but it is difficult to kill the eggs.