The house centipede, Scutigera coleoptrata, is an arthropod frequently encountered in human dwellings across the globe, often causing immediate alarm due to its startling appearance and speed. This myriapod is related to other centipedes and millipedes and is recognized as one of the most widespread species found indoors. While their sudden, rapid movements can be unsettling, understanding their biology and behavior reveals that their presence is rarely cause for serious concern. Their interaction with the indoor environment is driven by their need for specific environmental conditions and predatory hunting habits.
Distinct Physical Traits
The house centipede is instantly identifiable by its elongated body and numerous, extremely long legs. The main body of an adult typically measures between one and one and a half inches in length, but the combined length of its antennae and rear legs can make the creature appear much larger, up to four inches overall. The body is segmented into 15 sections, each bearing a single pair of legs.
Their coloration is usually yellowish-gray, often marked by three dark, longitudinal stripes running down the back. The legs are banded with alternating light and dark colors, contributing to their complex look when moving quickly. Unlike most other centipedes, the house centipede possesses well-developed faceted eyes, aiding its active hunting style. The pair of legs beneath the head are modified into specialized structures called forcipules, used to capture and subdue prey.
Indoor Habitat and Behavior
House centipedes are primarily nocturnal, retreating to dark, secluded areas during the day. They are highly dependent on moisture and humidity because they lack a waxy cuticle layer to prevent water loss, unlike many insects. This physiological need explains their preference for damp indoor locations such as basements, crawl spaces, bathrooms, and areas around floor drains.
They typically enter structures from the outdoors through cracks in foundations, gaps around windows and doors, or uncapped concrete blocks. Once inside, they do not chew on wood, fabric, or stored food products. The sight of a centipede often signals a moisture issue or excessive clutter, both of which provide suitable habitat and hiding places. When disturbed, they exhibit remarkable speed, darting across surfaces or up walls to find refuge.
Threat Level and Diet
Despite their intimidating appearance and rapid movement, house centipedes pose a negligible health risk to humans. They are active predators that use their modified front legs (forcipules) to inject paralyzing venom into their prey. However, their venom apparatus is designed for small invertebrates, and the forcipules are often too weak to pierce human skin successfully.
Bites are extremely rare, typically only occurring if the centipede is handled or provoked. If a bite does penetrate the skin, the effect is usually minor, with symptoms comparable to a mild bee sting, such as temporary pain and slight swelling. House centipedes are beneficial within the home environment because they actively hunt and consume common household pests. Their diet includes spiders, silverfish, firebrats, carpet beetle larvae, cockroaches, and even bed bugs.
Management and Prevention
The most effective strategy for managing house centipedes is to eliminate the two main factors that attract them: moisture and food sources. Controlling the humidity level in the home is a primary step, particularly in basements and crawl spaces, ideally maintaining indoor humidity below 50% using a dehumidifier. Repairing leaky pipes, ensuring proper ventilation in bathrooms, and removing damp organic materials from around the foundation also reduce their preferred habitat.
Sealing entry points prevents house centipedes from entering. This involves using caulk to fill cracks and crevices in the foundation, sealing gaps around utility lines, and ensuring weather stripping around doors and windows is intact. Reducing the population of other small pests through cleaning and sticky traps will diminish the centipede’s food supply. For individual centipedes encountered inside, non-lethal removal methods, such as capturing them under a cup and releasing them outdoors, are simple and effective.