Centipedes and millipedes are arthropods, not insects, because insects have only six legs - whereas, as their names imply, centipedes and millipedes have many more. Although they can be a nuisance and displeasing if found in the home, they are considered to be occasional invaders because they generally wander into homes and buildings accidentally rather than seeking a place to live or breed.
How to tell the difference between centipedes and millipedes
- Body: can be as short as 1/4 inch in length or as long as 6 inches. They body is made up of 15 or more segments, all of similar size.
- Legs: centipedes have one pair of legs on each body segment. These legs are as dominant as body; more similar to a caterpillar than a worm. The first pair has a set of poison claws, or fangs, which they use to paralyze their prey. The back legs are longer than the others and are used as antennae.
- Color: yellowish- to dark brown or even reddish green.
- Food: feed on small insects, spiders, earthworms, snails.
- Movement: Centipedes can move about very quickly on their long legs.
- When disturbed: centipedes will scurry away quickly.
- Where live: centipedes prefer dark, moist hiding places, such as under stones, boards, sticks, leaves, organic matter outdoors, and in basements and bathrooms indoors.
- Threat: centipedes of the U.S. rarely bite, but when they do, it can redden and swell similar to a bee sting. In other areas of the world where centipedes are often larger, their bite can cause a burning pain.
- Body: up to 1 1/2 inches long (except the Beauvois species found in Texas that can be up to 4 inches in length).
- Legs: millipedes have two pair of legs on each body segment. legs are shorter in relation to body, so have more of a worm-like appearance.
- Color: brown to black, rounded body.
- Food: organic material and some young plants.
- Movement: millipede movement is slower with a wave-like look.
- When disturbed: millipedes will curl into a ball, like pillbugs or sowbugs.
- Where live: millipedes live primarily in organic materials such as leaves, mulch and wood chips.
- Threat: millipedes do not bite, but may eject a fluid that can irritate skin or eyes, have a foul smell, and cause allergic reaction in sensitive individuals.
Damage and Disease
In general, these many-legged pests cause no danger or harm to people or pets; are not known to transmit any diseases to humans; and do not damage food, plants, furniture or structure as do other more harmful pests, such as cockroaches, rodents, and flies.
Because they require moisture and foods such as organic material or insects to survive, millipedes and centipedes will not be able to live for long or reproduce within the dry home environments.
Control of Centipedes and Millipedes
- Find the source - centipedes and millipedes need moisture to survive, so if they are living in your home, there may be a moisture problem that should be repaired.
- Remove any organic material that is within a few feet of the home, including mulch, wood-chip landscaping, and moisture-holding ground cover.
- Inspect for and eliminate moist areas near the exterior of the home where centipedes or millipedes may be living.
- Store firewood away from the structure and inspect for clinging bugs and insects prior to bringing into the home.
- Seal around doors and windows, particularly those that are low-lying.
- A perimeter treatment, around the foundation, about two feet up the outside walls, and one to two feet out from the home, with an insecticide labeled for this insect and use can help decrease invasion by these pests. Follow all label directions when using any pesticide.
- If found in the home, simply vacuum or sweep up, squashing and discarding or releasing the arthropods outside.