Lepisma saccharinum
Philipp · CC0Completely harmless. No bite, no sting, no venom and no disease. It damages paper, book bindings and starched fabric, and that is the entire extent of what it does.
Across the United States, in buildings almost universally.
Bathrooms, kitchens, basements, and inside stored paper, books and cardboard. Anywhere humid, dark and undisturbed.
It eats starch and cellulose — paper, glue in book bindings, wallpaper paste, starched linen and dry pantry goods — and it needs high humidity to survive, which is why bathrooms suit it. It is nocturnal and fast, and it cannot climb smooth vertical surfaces, which is why one so often ends up stranded in a bath or sink where it fell in and could not get out. It is long-lived for an insect, reaching several years, and it keeps moulting throughout adult life, which almost no other insect does.
Reduce humidity — that is the whole solution. Ventilate bathrooms, fix leaks, run a dehumidifier in a damp basement, and store paper and books somewhere dry. They cannot maintain a population in genuinely dry conditions, so nothing needs spraying.
No. They have chewing mouthparts suited to paper and starch and cannot bite people. There is no venom and no disease risk.
It fell in and cannot climb out — smooth porcelain defeats them. It was not coming up the drain, which is the usual assumption.
Starch and cellulose: paper, book glue, wallpaper paste, starched fabric, and dry goods like flour and oats. Damage to books and stored documents is the real cost.
Take the humidity away. Ventilation, leak repair and a dehumidifier do more than any insecticide, because the population depends entirely on damp.
Identify another animal from a photo or return to the Other guide.
Last reviewed 2026-07-30. We identify, we don’t diagnose — what we can and can’t tell you.