House centipedes (Scutigera coleoptrata) are frequently encountered in homes, often causing alarm due to their appearance. Understanding their nature can help clarify their safety and reasons for their indoor presence.
Identifying House Centipedes
House centipedes possess distinct physical characteristics. Their bodies are typically yellowish-gray, measuring 25 to 35 mm (1.0 to 1.4 inches) in length, though their long legs and antennae can make them appear up to 75 to 100 mm (3 to 4 inches) long. They feature three dark dorsal stripes along their length, with their numerous legs also displaying dark bands. They have up to 15 pairs of elongated legs, with the last pair often being the longest, contributing to their feathery appearance and enabling rapid movement across surfaces.
Assessing Their Harmlessness
Despite their unsettling appearance, house centipedes are generally considered harmless to humans and pets. They do not transmit diseases or harmful bacteria. While they possess venom, it is primarily for subduing insect prey and not potent enough to significantly harm humans or common household pets.
A house centipede bite is rare, as they typically retreat from perceived threats. If a bite occurs, it is like a pinch or sting, causing mild, localized symptoms such as slight pain, redness, and swelling, comparable to a bee sting. In rare instances, an allergic reaction, similar to bee venom reactions, may require medical attention. House centipedes are beneficial, preying on household pests like spiders, silverfish, cockroaches, bed bugs, and ants, helping control their populations.
Why They Appear Indoors
House centipedes enter homes primarily in search of food, water, and shelter. They are attracted to environments offering protection, consistent food sources, and suitable conditions. These arthropods thrive in dark, damp, undisturbed areas like basements, bathrooms, crawl spaces, and garages, which provide the moisture they require.
Their presence indoors often indicates a larger underlying pest issue, as centipedes are drawn to homes with abundant prey. They are nocturnal hunters, hiding during the day and emerging at night to seek out their prey. Severe outdoor weather, like heavy rain or extreme temperatures, can also drive them indoors in search of more hospitable conditions.
Managing Their Presence
Managing house centipedes involves reducing their attractants. Addressing other household pest problems is a primary step, as eliminating their food source will discourage centipedes from remaining in your home. Keeping your living space free of clutter and food crumbs helps prevent the insects that centipedes feed on.
Reducing moisture and humidity levels is also important, as centipedes prefer damp environments. This can be achieved by using dehumidifiers in basements and crawl spaces, repairing leaky pipes, and ensuring proper ventilation in areas like bathrooms and attics. Sealing cracks and gaps in your home’s foundation, around windows, and entry points can prevent centipedes and other pests from entering indoors.