Silverfish Pest Library Entry:

Order= Now Zygentoma, Previously Thysanura (Bristletails)

Common Pest Species:

Common Silverfish (Lepisma saccharina)

Gray Silverfish (Ctenolepisma longicaudata) aka Urban, Giant, and Long-Tailed Silverfish

Four-Lined Silverfish (Ctenolepisma lineata)

Firebrat (Thermobia domestica)

Active Times: Nighttime (Nocturnal)

Characteristics (Appearance/Habitation/Etc.):

Silverfish and Firebrats range in their coloration. Silverfish species are commonly metallic silver with some brown colored variant species. Firebrats generally have a mottled gray-brown coloration. Both are generally half an inch to one inch in length with adults having scales. Species are wingless and do not fly. They have flattened body types which taper at the end and gives them the ability to flatten between tight spaces to hide in. Two long antennae on the head and three long filaments on the bottom tips of the body resembling a tail are characteristic to both. They move extremely fast to avoid predators and any perceived threat.

Silverfish are generally found underneath rocks and leaf litter in cool damp areas, and in the home such places with moisture that are cool and dark like bathrooms, garages, cellars, kitchens, closets, and etc.  are all common places to find them. Firebrats prefer to be in extremely warm dark damp areas such as cellars and basements with boilers and furnaces.

One exception is the Four-Lined SIlverfish, a European species gaining footing in the U.S. invasively who prefers either extremely dry climates such as California/Arizona or extremely wet humid areas to live in such as the East Coast as far south as Georgia and as far in midwest as Arkansas.

It should be noted that many species of Silverfish and Firebrats are grouped under the same order, but are not necessarily the same, just closely enough related and similar in general characteristics. Most of them are considered in the public domain as being grouped under one general name, but depending on the area that can range from Silverfish, Bristletails, Firebrats, Fishmoths, and etc.


Silverfish Eggs can be laid in numbers of 50 at a time and can take two weeks to a couple months in order to hatch. Some Silverfish species live as long as up to 7 years old, many sustaining 3-5 years of age.

Firebrats females lay eggs upwards of 50 eggs that can only survive in areas with temperatures between 90 and 112 degrees fahrenheit (Boiler Rooms & Basements with Furnaces) and they live an average of 1-2 years.

Diet: Generalist

Silverfish and Firebrats like starchy foods and sugars such as those found in pantries. They have also been known to eat various fabric/cloth materials and the glue holding book pages together. They can go without food for upwards to three months if water is accessible to them, making them a tricky pest to treat for due to their inconsistent eating periods.

Diseases: N/A for both Silverfish and Firebrats

Notes/Research Sources:





http://www.entomology.ucr.edu/ebeling/ebeling8.html#ctenolepisma%20lineata *

http://extension.missouri.edu/publications/DisplayPrinterFriendlyPub.aspx?P=g7376 *PRINT!










*Bristletails are a common name for both Silverfish and Firebrat species.

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