ILLINOIS PEST IDENTIFICATION GUIDE

House Centipedes of Illinois

House centipedes are fast, long-legged predators that commonly appear in basements, bathrooms and other sheltered parts of Illinois homes. Their many legs and sudden movement look alarming, but they spend their time hunting smaller insects.

This guide covers identification, behavior, diet, life cycle, risks, habitat and the difference between centipedes and millipedes.

House centipede identification photograph

How to Identify a House Centipede

  • Adult body roughly one to one-and-one-half inches long, appearing much larger when the legs are included
  • Fifteen pairs of extremely long, delicate legs
  • Yellowish gray body with three dark longitudinal stripes
  • Long antennae and a final pair of legs that can resemble antennae
  • Very fast, darting movement across walls and floors

The scientific name of the common house centipede is Scutigera coleoptrata. Young centipedes hatch with fewer legs and add more pairs as they molt.

House centipede showing long banded legs and striped body

Where House Centipedes Live

House centipedes need protected areas with access to moisture and prey. Inside, they are commonly found in basements, crawl spaces, bathrooms, laundry rooms, utility rooms, closets and garages.

They hide during the day inside cracks, wall voids and beneath stored items. Most visible hunting occurs at night, when they run across floors or climb walls in search of insects.

What House Centipedes Eat

House centipedes are active predators. Their prey can include silverfish, spiders, cockroaches, crickets, moths, flies and other small arthropods.

They use modified front legs called forcipules to capture prey and deliver venom. This hunting behavior means repeated centipede sightings can be a clue that other insects are present.

Centipedes vs. Millipedes

Centipedes

  • One pair of legs per body segment
  • Flattened bodies built for fast movement
  • Predators that hunt other small animals
  • House centipedes have unusually long legs

Millipedes

  • Most body segments carry two pairs of legs
  • Rounded, cylindrical bodies
  • Slow-moving feeders on decaying plant material
  • Often curl into a coil when disturbed

House Centipede Life Cycle

Females deposit eggs in protected, moist locations. Newly hatched house centipedes begin with only a few pairs of legs and add additional pairs through successive molts until reaching the adult total of fifteen pairs.

Development can take several years, and adults may live for multiple years when shelter, moisture and prey remain available.

Do House Centipedes Bite?

House centipedes are not aggressive toward people and bites are uncommon. Their first response is usually to run and hide. A bite is possible if one is trapped against bare skin, but most indoor encounters do not result in injury.

They do not damage buildings, furniture or stored food. Their primary concern is nuisance activity and the possibility that prey insects are also living inside.

House centipede common in Illinois homes

Other Centipedes Found in Illinois

Illinois also has native stone centipedes and soil centipedes. These species usually live outdoors beneath logs, stones, leaf litter and soil where they hunt small invertebrates.

Stone centipedes are compact, flattened and fast-moving. Soil centipedes are long, narrow and adapted to moving through soil. They may wander indoors accidentally, especially after heavy rain or changes in moisture, but house centipedes are the species most adapted to living inside buildings.

Frequently Asked Questions

Why do house centipedes run so fast?
Their long legs and lightweight body are adapted for chasing prey and escaping danger. They can also climb walls and ceilings while hunting.
Does one house centipede mean I have an infestation?
A single centipede may have wandered from a hidden area, but repeated sightings suggest favorable moisture, shelter or prey insects. Monitoring and inspection provide better evidence than one sighting alone.
Should I leave house centipedes alone because they eat pests?
They do eat other insects, but frequent indoor activity can be unpleasant and may point to another pest problem. Reducing moisture and prey is a better long-term approach than relying on centipedes for control.

Seeing house centipedes repeatedly? See how D&K inspects the moisture, hiding places and prey insects behind the activity on our House Centipede Control Services page.

Return to the Pest & Wildlife Library