Pest Identification

Size:
Silverfish and bristletail adults are about 1/2-3/4 in (12-19 mm) long, not including tails.

Characteristics:
Bristletails and silverfish are wingless, with flattened bodies tapered from head to rear, covered with scales. They have 3 long bristle type appendages on the end. Antennae are long, threadlike. Compound eyes are small, widely separated. Silverfish, 1/2 in (12-13 mm), four lined silverfish, 5/8 in (16 mm) and gray silverfish, 3/4 in (19 mm) are representative species found in the U.S., including southern California.

Color:
Silvery to gunmetal colored, one species with dark lines along length of body.

Where found:
Throughout the United States and the world. 

Comparison with other species:
Firebrats are not silvery, usually mottled in color. Jumping bristletails have large compound eyes that touch each other; they jump when disturbed. Springtails lack the 3 appendages ("tails") but have a forked appendage at end of their bodies, and short antennae. Larvae and wingless adults of insects with complete metamorphosis do not have the 3 bristle like appendages.

Habitat:
Anywhere in houses, commercial buildings; can breed in a variety of places, such as wall voids, floors, attics. They thrive at room temperature and in high humidity.

Food:
Depends on species, but all can survive for weeks without food or water. They roam to search for food, but stay close to it once they find it. Silverfish (Lepisma saccharina) prefer protein to carbohydrates, are cannibalistic, and pests of paper. Gray silverfish feed on wheat flour and beef extract, especially in wallpaper paste, preferring papers with high chemical pulp content, such as cellophane, tissue, onion skin (instead of newsprint, cardboard, brown wrapping paper); they also eat linen, rayon, cotton (not wools or natural silk). Four lined silverfish, not so limited by temperature and moisture, live and feed indoors and outdoors, can digest cellulose, are sometimes found in attics near wooden shingle roofs, or under bark of Eucalyptus trees in California. 

Biology:
Varies with the different species. Eggs are laid in cracks. Nymphs molt a number of times. Silverfish and bristletails breed in a variety of places, in almost any room of the house, as well as in commercial structures. Some species can digest cellulose.

Damage:
These are nuisance pests, which leave surface etchings in paper, especially glazed paper, wallpaper, books.