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Gray Silverfish (Ctenolepisma longicaudata)

Detailing the identifying qualities of the Gray Silverfish, including physical features and territorial reach.

 Updated: 1/18/2014; Authored By Staff Writer; Content ¬©

  Gray Silverfish  
Picture of Gray-Silverfish

Gray Silverfish are usually spotted indoors, scurrying around floors and up walls, looking for a warm place to rest.

These fast insects are usually found around dark, warm places inside a home (ovens, furnaces, fireplaces, bathroom vents, clothes dryer). They are very flat and can run under baseboards and into other tight spaces to hide. It has three thread-like tails found at tip of its abdomen. Silverfish bodies are covered in flexible and slippery scales that help prevent the insect from capture by bigger things like centipedes and spiders.

All Silverfish are attracted to dry, starchy substances, which comprise their food. It is not unusual to find them wandering around in pantries where bags of flour, sacks of potatoes and other starchy delights are stored. The crusty glue that binds old book pages together is also source of food to Gray Silverfish. It is also not unusual to find them in the pages of old books, or running even around libraries. Gray Silverfish can live for months without eating. They are harmless to humans, though many humans consider them a nuisance.

Another interesting fact about these insects is how long it takes them to mature. Some Silverfish need 2 years to become fully-grown adults, and other species take even longer.

Gray Silverfish Information

Category: Bristletail
Common Name: Gray Silverfish
Scientific Name: Ctenolepisma longicaudata
Other Name(s): Silverfish

Taxonomy Hierarchy

 Arrow graphic Kingdom: Animalia
  Arrow graphic Phylum: Arthropoda
   Arrow graphic Class: Insecta
    Arrow graphic Order: Thysanura
     Arrow graphic Family: Lepismatidae
      Arrow graphic Genus: Ctenolepisma
       Arrow graphic Species: longicaudata

Size, Identifying Tags and Territorial Reach

Size (Adult, Length): Size (Adult, Length): 10 mm to 20 mm (0.39 inches to 0.78 inches)
Identifying Colors: gray, black, silver
Additional Descriptors: fast, tail, three, flat, silver

North American Territorial Reach (Though Not Limited To): Alabama; Alaska; Arizona; Arkansas; California; Colorado; Connecticut; Delaware; Florida; Georgia; Hawaii; Idaho; Illinois; Indiana; Iowa; Kansas; Kentucky; Louisiana; Maine; Maryland; Massachusetts; Michigan; Minnesota; Mississippi; Missouri; Montana; Nebraska; Nevada; New Hampshire; New Jersey; New Mexico; New York; North Carolina; North Dakota; Ohio; Oklahoma; Oregon; Pennsylvania; Rhode Island; South Carolina; South Dakota; Tennessee; Texas; Utah; Vermont; Virginia; Washington; West Virginia; Wisconsin; Wyoming; Alberta; British Columbia; Manitoba; New Brunswick; Newfoundland and Labrador; Nova Scotia; Ontario; Prince Edward Island; Quebec; Saskatchewan; Mexico

A Note About Territorial Reach: Keep in mind that an insect's reach is not limited by lines drawn on a map and therefore species may appear in areas, regions and/or states beyond those listed above. Insects are driven by environmental factors, food supplies and mating patterns and do not nescessarily work within hard-and-fast territorial lines like we humans do.

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