Types of Centipedes, Millipedes & Crawlers: 7 Common Species
Wingless ground crawlers, many with far more than six legs. This guide covers the 7 centipedes, millipedes & crawlers people find most often.
How to narrow it down
Narrow it down with three quick checks. Count the legs: insects have six, spiders and ticks have eight, and centipedes and millipedes have many more. Check for wings, even folded ones. Then compare size against a coin: a US penny is 19 mm across. Our bug identifier tool does this filtering for you.
The 7 bugs
Earwig
EarwigForficula auriculariaA slender, reddish-brown insect with a pair of pincers on its tail. Earwigs hide under mulch and pots by day and chew seedlings, flowers and soft fruit at night.
Tell-tale sign: Forceps-like pincers at the end of the abdomen. Risk: Earwigs can pinch but are harmless, and they do not crawl into ears.
House Centipede
House CentipedeScutigera coleoptrataA fast, yellowish-gray centipede with 15 pairs of very long legs that races across floors and walls at night. It hunts silverfish, cockroaches and spiders.
Tell-tale sign: Fifteen pairs of long, banded legs. Risk: House centipedes rarely bite; a bite feels like a mild bee sting.
Millipede
MillipedeOxidus gracilisA slow-moving, cylindrical arthropod with two pairs of legs on most body segments. Millipedes eat decaying leaves and often migrate indoors after heavy rain.
Tell-tale sign: Rounded, segmented body with many short legs. Risk: Millipedes don't bite; some release a fluid that can stain or irritate skin.
Silverfish
SilverfishLepisma saccharinaA wingless, carrot-shaped insect covered in silvery scales that moves with a fish-like wiggle. It eats paper, glue, starches and fabrics in damp areas.
Tell-tale sign: Silvery-gray, teardrop-shaped, scaly body. Risk: Silverfish don't bite; they damage books, wallpaper and stored papers.
Booklouse
BooklouseLiposcelis spp.A tiny, soft, pale insect that feeds on microscopic mold growing on paper, cardboard and stored food. It thrives in humid rooms and new construction.
Tell-tale sign: Very small, pale, wingless body. Risk: Booklice don't bite and aren't true lice; they indicate high humidity and mold.
Pill Bug
Pill BugArmadillidium vulgareA small land crustacean that rolls into a tight ball when disturbed, also called a roly-poly. It eats decaying plant matter in damp soil and mulch.
Tell-tale sign: Gray, armored, segmented body with seven pairs of legs. Risk: Pill bugs are harmless and only occasionally nibble seedlings.
Springtail
SpringtailCollembola classA tiny, wingless hexapod that jumps using a tail-like spring folded under its body. Springtails swarm in damp soil, potted plants and around leaks.
Tell-tale sign: Pinhead-size gray, white or black body. Risk: Springtails don't bite or damage homes; large numbers usually point to a moisture problem.
Which ones should you worry about?
0 of the 7 bugs in this guide can bite or sting. None of them are considered medically significant. The rest are harmless or simply a nuisance.
Comparison at a glance
| Earwig | House Centipede | Millipede | |
|---|---|---|---|
| Group | Centipedes, Millipedes & Crawlers | Centipedes, Millipedes & Crawlers | Centipedes, Millipedes & Crawlers |
| Scientific name | Forficula auricularia | Scutigera coleoptrata | Oxidus gracilis |
| Size | 12–20 mm | 25–35 mm | 20–40 mm |
| Colors | Brown and Red | Gray, Tan and Yellow | Brown and Black |
| Legs | 6 legs | many legs (30 or more) | many legs (30 or more) |
| Wings | Yes | No | No |
| Bites or stings | No | Bites | No |
| Risk | Nuisance | Nuisance | Nuisance |
| Key feature | Forceps-like pincers at the end of the abdomen | Fifteen pairs of long, banded legs | Rounded, segmented body with many short legs |
Frequently asked questions
What is the most common one?
Among the bugs in this guide, the earwig and house centipede are the ones people ask about most.
Which of these are dangerous?
None of them are medically significant, though some can bite or sting.
How can I identify a bug I found?
Use the free bug identifier tool: choose the number of legs, wings, main color, size and where you found it, and it will list the closest matches.