This article is about the most common insect species referred to by this name,Lepisma saccharinum. For the larger group of insects included under this name, seeZygentoma. For other uses, seeSilverfish (disambiguation).
Thesilverfish (Lepisma saccharinum) is a species of small,primitive,[1] winglessinsect in theorderZygentoma (formerlyThysanura). Itscommon name derives from the insect's silvery light grey colour, combined with the fish-like appearance of its movements. Thescientific name (L. saccharinum) indicates that the silverfish's diet consists ofcarbohydrates such assugar orstarches. While the common namesilverfish is used throughout the global literature to refer to various species of Zygentoma, theEntomological Society of America restricts use of the term solely forLepisma saccharinum.[2]
The silverfish is anocturnal insect typically 13–25 mm (0.5–1.0 in) long.[3] Its abdomen tapers at the end, giving it a fish-like appearance.[4] The newly hatched are whitish, but develop a greyish hue and metallic sheen as they get older.[5] It has two longcerci and one terminal filament at the tip of theabdomen between the cerci. It also has two smallcompound eyes, although other members ofZygentoma are eyeless, such as the familyNicoletiidae.[4][6]
The silverfish, like other species inApterygota, is wingless.[4][7] It has longantennae, and moves in a wiggling motion that resembles the movement of afish.[8] This, coupled with its appearance and silvery scales, inspires its common name. Silverfish can regenerate lost terminal filaments and antennae within four weeks.[9] Silverfish typically live for up to three years.[10]
The silverfish is an agile runner. It avoids light.[11]
Before silverfish reproduce, they carry out a ritual involving three phases, which may last over half an hour. In the first phase, the male and female stand face to face, their vibrating 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.[14] Finally, the male lays aspermatophore, a sperm capsule covered ingossamer, which the female takes into her body via herovipositor to fertilize her eggs. The female lays groups of fewer than 60 eggs at once, deposited in small crevices.[15] The eggs are oval-shaped, whitish, about 0.8 mm (0.031 in) long,[16] and take between two weeks and two months to hatch. A silverfish usually lays fewer than 100 eggs in her lifetime.[3]
When thenymphs hatch, they are whitish in colour, and look like smaller adults.[1] As theymoult, young silverfish develop a greyish appearance and a metallic sheen, eventually becoming adults after three months to three years.[15] They may go through 17 to 66 moults in their lifetimes, sometimes 30 in a single year—many more than most insects. Silverfish are among the few types of insect that continue to moult after reaching adulthood,[17]with an estimated lifespan of around 2 to 8 years.[18]
Silverfish are considered householdpests, due to their consumption and destruction of property.[3] However, although they are responsible for the contamination of food and other types of damage, they do not transmit disease.[5][21]House centipedes andspiders such as the spitting spiderScytodes thoracica are known to bepredators of silverfish.[22][23][24]
Theessential oil of the Japanese cedarCryptomeria japonica has been investigated as arepellent andinsecticide againstL. saccharinum, with promising results: filter paper impregnated with oil repelled 80% of silverfish at a gas concentration of 0.01 mg/cm3, and an exposure of 0.16 mg/cm3 for 10 hours caused a 100% mortality rate.[25]
The scientific name for the species isLepisma saccharinum[26] (originallysaccharina; Linnaeus' 1758 descriptionhere), due to its tendency to eatstarchy foods high in carbohydrates and protein, such asdextrin.[5] However, the insect's more common name comes from its distinctive metallic appearance and fish-like shape.[27] While the scientific name was established byCarl Linnaeus in his 175810th edition ofSystema Naturae, the common name has been in use since at least 1855.[28][29] Most authors have historically treated the nomenclatural gender ofLepisma as feminine (also as specified in ICZN Direction 71 issued in 1957), but in 2018 theInternational Commission on Zoological Nomenclature reversed this decision, issuing a new formal ruling (ICZN Opinion 2427) stating the gender ofLepisma (and all genera with that ending) is neuter, following ICZN Article 30, which resulted in changes to the spelling of several well-known species, includingLepisma saccharinum.[30]
The predecessors of silverfish, along with those ofjumping bristletails, are considered the earliest and mostprimitive insects. They evolved at the latest in mid-Devonian and possibly as early as lateSilurian more than 400 million years ago.[31] Some fossilizedarthropod trackways from thePaleozoic Era, known asStiaria intermedia and often attributed to jumping bristletails, may have been produced by silverfish.[32]
TheAustralian species most commonly referred to as silverfish is a different lepismatid,Acrotelsella devriesiana.[4] Thefirebrat (Thermobia domestica) is like a silverfish, but with a mottled gray and brown body.[33]
^abParkinson B. J. & Horne D. (2007).A photographic guide to insects of new zealand. New Holland. p. 14.ISBN978-1-86966-151-9.
^Phillips, Eleanor F.; Gillett-Kaufman, Jennifer L. (2018)."Silverfish - Lepisma saccharina".Featured Creatures - Entomology and Nematology Department, University of Florida. Retrieved10 January 2021.
^Hoell, H. V., Doyen, J. T. & Purcell, A. H. (1998).Introduction to Insect Biology and Diversity, 2nd ed. Oxford University Press. pp. 333–340.ISBN0-19-510033-6.{{cite book}}: CS1 maint: multiple names: authors list (link)
