Bug FAQCommon Pill Millipede
Glomeris marginata · Order: Glomerida · Family: Glomeridae
Also called: Pill Millipede, bordered pill millipede
The common pill millipede rolls into a ball and has dark, shiny plates with lighter rims that may be black, brown, red or yellow. It lives in leaf litter, grass and under stones, especially on calcareous soils and in garden hedgerows where lime leaches from old mortar.
Source: Wikipedia
How to recognize it
Its back plates (tergites) are usually black with lighter edges, but can also appear brown, red or yellow. The outer shell is darker and shinier than that of a pill woodlouse.
Source: Wikipedia
Size
Females are 8 to 20 mm long and 4 to 8 mm wide; males are a bit smaller at 7 to 15 mm long and 3.5 to 6 mm wide.
Source: Wikipedia
Does it bite or sting?
When threatened it releases one to eight drops of a sticky fluid containing quinazolinone alkaloids that act as toxins and antifeedants.
Source: Wikipedia
Where it lives
It inhabits leaf litter, grass and the undersides of stones, preferring soils rich in calcium.
Source: Wikipedia
What it eats
It feeds on old, decaying leaves, helping recycle nutrients in leaf litter.
Source: Wikipedia
Life cycle
Juveniles take several years to become mature adults. Adults can live ten to eleven years, molting once each year and passing through up to sixteen stages.
Source: Wikipedia
When you see it
Adults are present year-round but are collected most often in spring and autumn. Males mature at stage seven and can breed by their second or third spring; females mature at stage eight and breed by their third or fourth spring.
Source: Wikipedia
Where it comes from
It is a European species of pill millipede.
Source: Wikipedia
More photos
Questions people ask
What does the common pill millipede do when it feels threatened?
It sprays a few drops of a sticky, toxic fluid that can deter ants and other predators.
Source: Wikipedia
How can I tell a pill millipede apart from a pill woodlouse?
Look for a darker, shinier back and the characteristic color pattern of the plates; woodlice have a different texture and coloration.
Source: Wikipedia
Sources
- Wikipedia: https://en.wikipedia.org/wiki/Glomeris_marginata
Look it up elsewhere: GBIF · iNaturalist · BugGuide · Wikipedia
Text written 2026-10-24 from the sources above and checked sentence by sentence against them. Data fetched 2026-10-22.