Stages of Life
The specific length of time between birth and adulthood depends on various environmental factors such as temperature, humidity, and food availability. Silverfish nymphs molt up to many times a year, and maturation may take anywhere from three months to three years. Silverfish are long-lived insects, with adults enjoying a lifespan of up to three years.
Silverfish begin their lives in tiny, white, oval-shaped eggs.
Where Do You Find Them?
Usually deposited into cracks and crevices in damp environments, silverfish eggs are laid in groups of 1 to 200.
Timeline for Hatching
When environmental conditions are adequate, they hatch within a few weeks. If temperatures drop below 50 degrees Fahrenheit, eggs can lay dormant until warmer conditions speed up the developmental process.
What Do Silverfish Larvae Look Like?
Silverfish larvae are very small, usually around 1/16 of an inch long. The insects do not undergo metamorphosis, so young silverfish are similar in appearance to adults with their lengthy antennae, six legs, and three long posterior appendages. Until they develop their characteristic silver scales after going through four molts, silverfish larvae have soft, white bodies. It takes approximately 40 days for them to develop into mature adults, though, where environmental conditions are unfavorable, the process can take over a year.
Despite their small size, silverfish larvae cause all the same problems as fully grown adults. They are just as capable of damaging paper and clothing products and are more likely to contaminate stored foods like cereals, grains, and flours. As they eat, silverfish larvae chew ragged holes in the pages of books, curtains, carpets, and wallpaper. The pests also defecate and leave yellowish stains behind when feeding.
Newly hatched silverfish are white and squishy as the pests do not grow their characteristic silver scales for several weeks. Once the scales come in, young nymphs have the appearance of tiny adult silverfish.
The insects continue to molt throughout their lives, maturing through over 60 instars and growing to an average size of 3/4 of an inch. It takes approximately 40 days for them to develop into mature adults, though, where environmental conditions are unfavorable, the process can take over a year.
Silverfish feed on cellulose matter and objects rich in starch or protein. Nymphs can cause just as much damage to books, paper products, stored foods, and clothing as adults since they need to feed in order to grow.
When temperatures are favorable, silverfish grow from eggs to sexually mature adults in the span of a couple months. However, in colder climates, the process can take as long as two years. Silverfish are one of the few insect species that continue to molt even after reaching maturity. Adults congregate in dank areas to mate, and female silverfish are capable of producing thousands of offspring over the course of their lives.
Adults live up to three years in ideal conditions.