Species Lepisma saccharinum - Common Silverfish

The gender of this genus is neuter, not feminine, following ICZN

Article 30, and explicitly clarified in ICZN Opinion 2427 in 2018."

the only species in this genus in North America

body length 10-12 mm

wingless; body flattened, slender, silvery, gray, or blackish above, and pale below; femora broad and flattened; tip of abdomen with 1 long medial filament and 2 lateral cerci often as long as the medial one, and projecting at right-angles to the body (filaments may be broken or missing); long thread-like antennae with many segments; mandibles articulate at two points; can run quickly but cannot jump

cosmopolitan

indoors in warm, damp environments such as bathrooms and kitchens, or in damp basements; rarely encountered outdoors

all year indoors; they are active at night, hide during the day, and avoid direct light

crumbs and food scraps, dried meat, cereals, moist wheat flour, glue on book bindings and wallpaper, starch in clothing made of cotton or rayon fabric

female lays eggs continuously after reaching adulthood, and may lay over 100 eggs in total; eggs are deposited singly or in small groups in cracks and crevices, and hatch in 3-6 weeks; young are white initially, becoming silver within 4-6 weeks; incomplete metamorphosis (egg, nymph, adult); adults continue to molt throughout their life, and may live 2-8 years; they can survive for weeks without food or water

the Four-lined Silverfish (formerly Ctenolepisma quadriseriata, now synonymized with C. lineata) has 4 lines down its back, and the Gray [or Giant] Siverfish (which includes the former Ctenolepisma urbana, now synomymized with C. longicaudata) is uniformly gray; both of these species are 15-19 mm long - significantly larger than the Common Silverfish (see images of the Four-lined Silverfish and the Gray Silverfish [ 1, 2 ])

the Firebrat (Thermobia domestica) is yellowish with dark brown bands and mottled spots on the dorsal surface, and is more stout-bodied (its abdomen is relatively broad-tipped and often shorter than the thorax, giving an overall "chunky" appearance); the Firebrat is normally found in hot places such as around furnaces and fireplaces, and in the insulation surrounding hot water and heating pipes

may also be confused with Bristletails (order Microcoryphia), which have large eyes that meet in the middle, a cylindrical body, an arched thorax, mandibles that articulate at only one point, are not normally found indoors, and have the ability to jump

live adult image courtesy of Clemson University, Alabama (insectimages.org)

live adult image (Invertebrates of Lake Baikal region, Russia)

live adult image (University de Liege, Belgium)

live adult image (Jurgen Peters, Germany)

preserved adult images and other info in French (Insects of Quebec)

images and info on the Common Silverfish and Firebrat (John Jackman and Phillip Hamman, Texas A&M U.)

overview of silverfish species (Walter Ebeling, U. of California at Riverside)

overview of silverfish species (PEI Pest Control, Canada)