silverfish

1 silver-gray wingless insect found in houses feeding on book bindings and starched clothing [syn: Lepisma saccharina]

2 a silvery variety of Carassius auratus [also: silverfishes (pl)]

English

Noun

silverfish (plural silverfish or silverfishes)

1. A small wingless insect with silvery scales, a type of bristletail.

Scientific names

• Lepisma saccharina

Translations

• CJKV Characters: 蟫
• Chinese: 銀魚, 银鱼
• German: Silberfisch , Silberfischchen , Zuckergast
• Hebrew: דג כסף
• Russian: сахарная чешуйница /sáχarnaja češújnica/
• Spanish: lepisma , pececillo de plata

Lepisma saccharina' (commonly called the fishmoth, urban silverfish or just the silverfish) is a small, wingless insect typically measuring from a half to one inch (12–25 mm). 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 over 300 million years, originating in the Paleozoic Era. 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.

Diet

The favorite 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 or disgusted 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 fibers, 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.ref UARK Silverfish can be found anywhere in your home including, but not limited to, garages, closets, underneath beds, couches. Silverfish like the dark. They sometimes eat off of left-over skin or dry skin.

Reproduction and growth

The reproduction of silverfish is preceded by a "love dance", involving three phases, which may last over half an hour. In the first phase, the male and female stand face to face, their trembling antennae touching, then repeatedly back off and return to this position. In the second phase the male runs away and the female chases him. In the third phase the male and female stand side by side and head-to-tail, with the male vibrating his tail against the female. Finally the male lays a spermatophore, a sperm capsule covered in gossamer, which the female takes into her body via her ovipositor to fertilize the eggs she will lay later on.

Juvenile silverfish are white in color.

Under laboratory conditions, silverfish may go through between 17 and 66 molts, much more than usual for an insect. Silverfish are one of the rare insects that continues to molt after mating.

Predation

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

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 live. 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
• To capture silverfish, trap in small glass containers -- silverfish cannot climb up the smooth inside walls.
• Silverfish can also be caught by sprinkling plaster on a wet white cotton cloth put in a corner overnight, near the silverfish's hideout.
• Placing moth balls in 4 corners of room is said to keep silverfish away from wall paper.

Lethal

• 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.

References

External links

• Silverfish factsheet at Virginia Tech, Department of Entomology
• http://www.uos.harvard.edu/ehs/pes_silverfish.shtml Harvard University factsheet on silverfish and firebrats
• Frequently Asked Questions about Silverfish at Cornell Cooperative Extension, Insect Diagnostics Laboratory
• Magnified pictures of Silverfish