firebrats

Firebrats (Thermobia domestica) are small, wingless insects in the order Zygentoma. They are closely related to silverfish and share a carrot-shaped body with three tail-like appendages. Adults typically measure about 10 to 15 millimeters in length and have a mottled gray‑brown coloration.

Firebrats prefer warm, humid environments. They are commonly found in heated buildings such as boiler rooms, hot water pipes, ovens, and furnaces, but can also occur in greenhouses and warm outdoor areas in mild climates. They are nocturnal and quick runners, retreating to cracks or clutter by day.

They feed on a variety of starchy substances, including paper, glue, book bindings, dried foods, textiles, and other organic materials rich in carbohydrates. They rarely transmit disease, but can cause damage to books, wallpaper, fabrics, and stored foods in infested environments.

Firebrats undergo ametabolous development, meaning nymphs resemble adults and molt as they grow. Eggs hatch after several weeks to months, depending on temperature. Nymphs molt through numerous instars over several months to years before reaching adulthood. At warmer temperatures, development is faster; at cooler conditions, it slows.

Effective management focuses on sanitation and environmental modification. Reduce humidity, fix leaks, improve ventilation, and seal cracks and crevices to limit access. Remove food sources and clutter. Insecticidal baits, residual sprays, and desiccants such as diatomaceous earth may help, but professional treatment may be required for severe infestations. Long-term control relies on eliminating the warm microhabitats these insects rely on.