If you are trying to identify a millipede, start with body shape. This guide helps you tell cylindrical, flat-backed and pill millipedes apart by their visible build, markings and size.

Once you can recognise those main forms, it becomes much easier to narrow down what you are looking at and compare it with the right species information. If you want to go further after identification, our more detailed Millipede Species Care Guides are the next step.

How to identify a millipede at a glance

The quickest clue is overall body shape. Even when a millipede is partly hidden or curled, its outline usually gives away the main group.

Cylindrical millipedes are rounded in cross-section and tend to keep a fairly even width along the body. Flat-backed millipedes are broader and more compressed, with a more obvious flattened profile. Pill millipedes are smaller and more compact, with a domed shape and the ability to roll into a tight ball.

Movement can add context, but it is not usually the best identification feature on its own. A millipede seen above the substrate may simply be a more surface-dwelling species, while one that stays buried may be acting normally for its type.

Colour, shape and markings

Colour is often the first thing people notice, but it should be read alongside the body's shape and structure. Millipedes may be dark brown, black, chestnut, reddish, orange or patterned, and some show banding between segments while others are more uniform.

Look for details such as smooth segments, visible ridges, flattened sides or a more tapered rear end. A broad, flattened millipede will look very different from a slim cylindrical one, even if both are similarly coloured.

Size is useful too, but only when handled carefully. Juveniles are often much smaller than adults and may not yet show full colour or pattern. Adult size can also vary, so a large individual is not automatically a giant species and a small one may simply be immature.

Scientific names are helpful when common names are used loosely. They make it easier to match photos, listings and care notes to the same animal.

How to tell similar types apart

When two millipedes look alike, the most useful clues are usually structural. Ask whether the body is round, flattened or compact; whether the animal has obvious bands or a more even tone; and whether the outline is smooth, ribbed or strongly segmented.

These differences matter because they often point to different species groups. A giant cylindrical millipede, a flat-backed millipede and a pill millipede can all have very different visible proportions, even before you get into species-level detail.

If you are comparing live examples, start with the side profile and overall build rather than colour alone. Photos can help, but a live animal viewed from above and side-on usually gives the clearest idea of shape.

What these differences mean for keepers

Identification matters because it helps you match the animal to the kind of enclosure experience you want. Some species are chosen for their size and presence, while others are more compact or more often seen in the open.

That is why body form is such a useful first step. It helps you separate a millipede that is likely to stay under cover for much of the time from one with a more obvious, surface-visible build.

If you are still deciding which type suits you, the current Millipedes for Sale UK collection is a useful place to compare live examples before checking the relevant guide.

In practice, the easiest way to identify a millipede is to start with body shape, then check colour, markings and size. Those visible cues are usually enough to separate cylindrical, flat-backed and pill millipedes before you move on to the species guides.