A fish out of water?

posted in: Natural Word | 2

Silverfish: I feel privileged that our house contains one or two of these shiny prehistoric creatures. I don’t see them often, as they appear in the kitchen at night, but from early childhood, finding one has always given me a thrill. Imagine if you had a time machine that could take you back 400 million years. You could find these when you got there.

Like other extremely ancient creatures such as sharks and millipedes, silverfish are obviously well designed for survival in their natural environment – otherwise they would have evolved into something else. Their legs may look flimsy, but silverfish can get away from predators such as spiders at great speed. The metallic sheen and curving fishtail shape earns them their common name. © Rowena Millar

Silverfish in the home

Silverfish are about the size of a woodlouse and are shy, harmless and inoffensive, unless you value that fragment of paper bag in the back of the cupboard, that mote of paste stuck to the back of some old, loose wallpaper, or that dusty piece of dandruff or flake of dried cereal under your cupboard. The scientific name (Lepisma saccharina) of this living fossil relates to its love of eating sugars and starches.

A night in the museum

An ancient silverfish fossil might perhaps be exhibited in a damp natural history museum basement while live ones gradually eat its label, including the ink and glue. Silverfish do need moisture. They can survive for up to a year without food, as long as there is water.

Friend or foe?

Pest control articles tell us that silverfish eat books or even clothing, but their mouths are tiny, they cannot fly or climb up slippery surfaces and they carry no diseases. You could move your more precious books or textiles to a drier place if you are worried, rather than destroying a fascinating animal.

Private life-cycles

I’ve never seen a silverfish mating ritual, but apparently it involves antennae quivering, chasing, and a silk-covered sperm capsule that is chastely picked up by the female, rather than inserted by the male. A female silverfish lays her eggs in hidden crevices. She may produce up to 100 of them in her two to eight years of life, whereas spiders can lay a few hundred eggs in a single season. Silverfish young look like tiny adults and unlike most other insects, continue moulting throughout their adult lives.

If you find one trapped in a sink or a bowl, simply tip it out gently, either where you found it or in another slightly damp place.

2 Responses

  1. Rosalie Gelling

    Very interesting, Rowena. People used to think they lived in dirty bakeries and were a threat to human health. Our own little family lived under a soggy front door mat. The babies were tiny gut as fast as the adults.

    • admin

      Dear Rosalie
      That’s very interesting. I rather like finding the occasional one in the kitchen, as they are so sleek in their silver armour.
      Very best wishes,
      Rowena

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