Bug Identifier

Centipedes, Millipedes & Crawlers

Millipede

Oxidus gracilis

010203040
Body length in millimeters. Shaded bar shows the typical adult range.
Scientific nameOxidus gracilis
GroupCentipedes, Millipedes & Crawlers
Size20–40 mm (up to about 1.6 in)
Colors Brown and Black
Legsmany legs (30 or more)
WingsNo (as usually seen)
Where foundBasement or garage and Garden or plants
Most activeSpring and Fall
BitesNo
StingsNo
Risk levelNuisance

How to identify it

The millipede is a large member of the centipedes, millipedes & crawlers group. Wingless ground crawlers, many with far more than six legs. Check for these three features:

  1. Rounded, segmented body with many short legs
  2. Curls into a tight coil when disturbed
  3. Slow, gliding movement

About this bug

A slow-moving, cylindrical arthropod with two pairs of legs on most body segments. Millipedes eat decaying leaves and often migrate indoors after heavy rain.

You'll usually find millipedes in basements and garages and in gardens and on plants. They are most active in spring and fall.

Is it dangerous?

Millipedes don't bite; some release a fluid that can stain or irritate skin.

Our rating: Nuisance, meaning it is a nuisance pest but not a health threat to most people.

When you'll see millipedes

Millipedes are most active in spring and fall. In spring, overwintering adults become active and many species lay their first eggs. In fall, many bugs look for shelter, and some move toward or into buildings.

Typical places to check: basement or garage and garden or plants.

About centipedes, millipedes & crawlers

The millipede is one of the centipedes, millipedes & crawlers. This group gathers wingless crawlers that people often lump together: centipedes, millipedes, silverfish, earwigs, springtails, booklice and pill bugs. Most need high humidity to survive and dry out quickly in dry air.

Because moisture is the common thread, a dehumidifier and fixed leaks often do more than any insecticide.

What to do about it

  1. Rake mulch and leaves back from the foundation
  2. Fix drainage so soil near the house dries out
  3. Seal door thresholds and low foundation cracks

Bugs that look similar

House CentipedeScutigera coleoptrata25–35 mmNuisance

Size: Millipedes are larger, reaching 40 mm, while house centipedes top out around 35 mm.

Pill BugArmadillidium vulgare8–14 mmHarmless

Size: Millipedes are larger, reaching 40 mm, while pill bugs top out around 14 mm.

Frequently asked questions

What does a millipede look like?

Rounded, segmented body with many short legs. Adults measure 20–40 mm (up to about 1.6 in).

Does the millipede bite or sting?

It does not bite. It does not sting. Millipedes don't bite; some release a fluid that can stain or irritate skin.

Where do millipedes live?

Millipedes live in basements and garages and in gardens and on plants.

When are millipedes most active?

Mostly in spring and fall.