The house centipede (Scutigera coleoptrata) is an arthropod that frequently enters human dwellings, often causing alarm due to its appearance and rapid movement. Despite its unsettling look, this creature is generally harmless to both humans and household pets. Native to the Mediterranean region but now found worldwide, the house centipede does not spread disease or cause structural damage to homes. It is a solitary predator whose presence typically indicates a different, more common pest issue within the structure.
Identifying the House Centipede
The house centipede has a distinctive physical form that contributes to its bad reputation. Its body is relatively small, typically measuring between one and one and a half inches in length. However, it possesses 15 pairs of extremely long, delicate legs that make it appear much larger, sometimes up to four inches long including the appendages. The body is yellowish-gray and marked with three dark longitudinal stripes running down its back.
These long legs and similarly long antennae allow the centipede to move with impressive speed, capable of darting across floors and walls at high velocity. They are nocturnal creatures, preferring to hide in cool, dark, and especially damp areas during the day. Homeowners most often encounter them in basements, crawl spaces, bathrooms, and utility closets, where humidity levels are typically higher. This preference for moisture is a biological necessity, as their respiratory system requires a humid environment to prevent dehydration.
Assessing the Threat: Bites and Venom
The house centipede is a predator that possesses venom delivered through modified front legs called forcipules. These pincer-like appendages are used to paralyze and kill small prey, not for attacking people. Bites to humans are extremely rare because the house centipede is non-aggressive and instinctively flees when disturbed. A bite usually only occurs if the centipede is handled roughly, accidentally trapped against the skin, or crushed.
For the house centipede, the forcipules are often too weak to successfully penetrate human skin. If a successful bite does occur, the experience is comparable to a mild bee sting. Symptoms are localized and minor, generally limited to pain, mild swelling, and redness at the site. The venom is not considered medically significant to humans, and symptoms resolve within a few hours to a few days without special medical treatment.
Unseen Benefits: Pest Control
Despite the initial fear they may cause, the house centipede provides a natural pest control service within the home environment. They are voracious, generalist predators that actively hunt a wide variety of other unwanted household arthropods. They use their speed and venom to quickly subdue these prey items, which are often far more destructive or numerous than the centipede itself. Their diet includes common pests such as:
- Silverfish
- Firebrats
- Carpet beetle larvae
- Cockroaches
- Spiders
The presence of a house centipede can be an indicator that a more significant pest issue exists, as they are drawn to a consistent food supply. By consuming these other arthropods, the centipede helps to regulate their populations, acting as a beneficial resident. This predatory role means they are not considered a destructive pest themselves, as they do not feed on wood, fabric, or stored food products.
Managing Their Presence
For individuals who find the house centipede’s presence unsettling, managing the environment can be an effective way to discourage them. Since they are strongly attracted to moisture, the most effective preventative measure is reducing humidity in areas like basements and bathrooms. Using a dehumidifier and ensuring proper ventilation with exhaust fans will make the environment less hospitable. Promptly fixing any plumbing leaks or moisture issues is also important.
To limit their entry, homeowners should inspect the exterior of the house and seal any cracks or gaps in the foundation, around windows, and near doors. Reducing the centipede’s food source is also a successful strategy; eliminating other household pests through regular cleaning and vacuuming will make the home less appealing. For direct removal, using sticky traps placed along baseboards or simply catching and releasing the centipede outside are humane alternatives to chemical treatments.