UK Millipede

Millipedes are among the most frequently encountered invertebrates in British gardens, woodlands, and compost heaps. These many segmented invertebrates belong to the class Diplopoda, a name derived from Greek roots meaning “double-footed”—a reference to the two pairs of legs found on most body segments. This article focuses on common species in the UK, including the white legged snake millipede (Tachypodoiulus niger) and flat backed millipede varieties like Polydesmus angustus, while enthusiasts may also encounter captive exotics such as the Ivory Millipede (Chicobolus spinigerus).

Introduction to UK millipedes

UK millipedes are slow moving creatures that play a vital role in recycling nutrients through British soils. You’ll find them in woodland leaf litter, under stones and bark, throughout gardens, and deep within compost heaps. Britain hosts more than 50 millipede species, though some are introduced and confined to glasshouses, while native ones vary considerably in size, appearance, and habitat preferences.

One familiar group includes the elongated snake millipedes with their cylindrical body shape, while another familiar group includes the broader flat-backed varieties with their distinctive flattened body profile. Despite having many legs—typically between 40 and 400—millipedes generally move in a slow, undulating wave-like motion rather than scurrying about.

Key takeaways:

• Millipedes have two pairs of legs on most body segments, unlike centipedes which have only one pair

• They are detritivores, feeding primarily on decaying matter rather than hunting prey

• Most UK millipedes are completely harmless to people

• Some species excrete almond smelling fluids or other pungent secretions as a defence mechanism

• They perform a useful nutrient recycling function in soil ecosystems

Millipede vs centipede: how to tell the difference

Millipedes and centipedes are often confused in the UK because they share similar habitats—both lurk under logs, rocks, and in leaf litter. However, these two myriapod groups are quite different once you know what to look for.

Leg arrangement:

• Millipedes have two pairs of legs per segment on most body segments, giving them anywhere from 40 to over 400 legs depending on species

• Centipedes have one pair of legs per segment and typically fewer total legs (usually 30-354)

• Despite having more legs, millipedes are actually slower than centipedes

Feeding habits:

• UK millipedes feed mainly on decaying vegetation, leaf litter, dead wood, and mildew

• Centipedes are nocturnal predators that use venomous forcipules (modified front legs) to catch invertebrate prey

• Millipedes have a nutrient recycling function; centipedes control pest populations

Body shape and movement:

• Millipedes have either a cylindrical body (snake millipedes) or a flat body (flat-backed species) and move slowly

• Centipedes have a dorsoventrally flattened body and are fast-moving hunters

• Very slow moving creatures like millipedes rely on defence rather than speed

Behaviour when disturbed:

• Millipedes curl into a tight spiral or ball and may release pungent or almond-scented fluids

• Centipedes tend to run away quickly, using their speed to escape predators

Common UK millipede species

Britain and Ireland host dozens of millipede species, but a handful are frequently encountered by anyone willing to turn over a log or sift through a compost heap. The following profiles cover the most common minibeast varieties you’re likely to find in gardens, woodland, and various habitats across the UK.

White-legged snake millipede (Tachypodoiulus niger)

Tachypodoiulus niger is one of the most recognisable millipedes in Britain, thanks to its striking appearance and widespread distribution.

• Size: Up to about 6 cm in length (typically 4-5 cm), making it one of the larger common UK species

• Appearance: Shiny, tubular black body with contrasting white legs that are immediately distinctive

• Juvenile colouration: Younger individuals are brown with pale longitudinal stripes before turning fully black as adults

• Body shape: Cylindrical body with numerous segments and a pointed tip (telson) at the rear

Habitat and distribution:

• Widespread across lowland England, Wales, and parts of Scotland and Ireland

• Found in deciduous woodland, gardens, allotments, and parkland

• Typically discovered under stones, logs, in leaf litter, or within rotting trees

• Can be seen year round in damp conditions, though most active in spring and autumn

Behaviour:

• Tends to curl into a spiral when disturbed

• Can release a pungent defensive secretion to deter predators

• Feeds on decaying organic matter and leaf litter

Flat-backed millipedes (e.g. Polydesmus angustus)

Flat-backed millipedes are easily recognised by their distinctive body shape. Unlike the rounded snake millipedes, these species have lateral “keels” or extensions on each segment, giving them a broad, segmented profile.

• Size: Polydesmus angustus January specimens typically measure around 2-2.5 cm long and about 4 mm wide

• Colour: Orangey brown or grey-brown body with pale legs

• Identifying feature: Flattened body segments with pronounced lateral extensions visible from above

• Segment count: Typically 19-20 body segments in adults

Habitat and distribution:

• Common in damp woodland across the UK

• Found under dead wood, deep in leaf litter, and in shaded garden borders

• Occasionally turn up in compost heaps where conditions are suitably moist

• December length surveys often record them in sheltered spots

Behaviour:

• Slow moving, preferring to hide in crevices rather than flee

• Can exude an almond-like smelling substance when handled or threatened

• Several similar species exist within this group, so detailed identification may require a hand lens and specialist keys

Striped millipede (Ommatoiulus sabulosus)

The striped millipede is one of the easier UK species to identify, thanks to its bold markings and relatively large size.

• Size: Up to about 3 cm long, with a thick cylindrical body

• Appearance: Dark brown or black background with one or two orange or yellowish stripes running lengthwise along the back

• Legs: Numerous pairs giving the characteristic rippling movement when walking

Habitat and distribution:

• Widespread in Britain and Ireland

• Especially common in meadows, rough grassland, sandy soils, and open woodland edges

• More tolerant of drier conditions than many UK millipede species

Behaviour:

• May be seen climbing low vegetation, walls, or tree bark

• Active during the day, grazing on algae and lichens

• Hides under litter or logs during hot or dry weather

• Bold stripes make it one of the easiest UK millipedes to identify without magnification

Other millipede forms in the UK

Beyond the common species described above, Britain hosts several other distinctive millipede groups worth knowing about.

• Pill millipedes (Glomerida): Can roll into a complete ball when threatened, resembles a woodlouse but with smoother, shinier plates and more legs

• Tunnelling millipedes: Slimmer, more streamlined species adapted for burrowing deeper into soil rather than living at the surface

• Leg count variation: Common UK species typically have between 40 and 200 legs, reflecting their different lifestyles and microhabitats

• Identification resources: UK-focused field guides such as AIDGAP keys or regional atlases provide detailed species-level identification for those wanting to go further

Habitats and lifestyle of UK millipedes

UK millipedes are terrestrial invertebrates that thrive in moist, sheltered environments rich in organic matter. Their distribution across Britain reflects their dependence on humidity and their role as decomposers in various ecosystems.

Typical microhabitats:

• Soil and leaf litter in deciduous and mixed woodland

• Under stones, logs, and loose bark on rotting trees

• Compost heaps and garden waste piles, where simple cucumber traps to find wild isopods can also reveal other detritivores

• Shaded garden borders, rockeries, and around tree stumps

• Damp cellars, greenhouses, and outbuildings

Activity patterns:

• Generally most active at night or during damp, overcast days

• Seek refuge from drying winds and direct sun

• Many species are present year round in the UK

• Observers most likely to encounter them in wetter months of spring and autumn

Feeding habits:

• Primary diet consists of decaying leaves and dead plant material

• Also consume mildew, microfungi, and algae growing on damp surfaces, much like woodlice feeding on decaying matter and fungi

• Eating mildew and fungal threads forms an important part of their nutrition

• Break down litter so microbes can complete decomposition

• Fragment material into pellets enriched with bacteria and fungi

Ecological importance and behaviour

Millipedes perform an important recycler role in UK ecosystems, from garden soils to ancient woodlands. Their contribution to nutrient cycling is often underappreciated, yet these invertebrates are essential components of healthy decomposer communities.

Nutrient cycling function:

• Feeding activity fragments dead leaves and wood into smaller pieces

• Increased surface area allows fungi and bacteria to work more efficiently

• Accelerates the return of carbon and minerals to the soil

• Particularly valuable where earthworm populations are low

• Their useful nutrient recycling function benefits plant growth

Defensive behaviours:

• Coiling into a spiral or ball to protect vulnerable legs and undersides

• Secreting foul-tasting or pungent chemicals from repugnatorial glands along their body

• Some species release hydrogen cyanide or other irritants

• Almond smelling fluids deter predators such as birds, shrews, and ground beetles

• Tough exoskeleton provides physical protection

Movement and speed:

• Despite their many legs, millipedes are relatively slow

• Rely on concealment and chemical defence rather than speed

• Characteristic wave-like leg motion moves them steadily but unhurriedly

Interactions with other soil fauna:

• Share habitats with earthworms, isopods such as woodlice, centipedes, springtails, and beetle larvae

• Form part of a complex decomposer community alongside other detritivores with similar roles, such as woodlice and their life cycle in decomposer habitats

• Provide food for various predators including hedgehogs and amphibians, while sharing decomposer niches with other invertebrates that can be supported by feeding isopods mealworm sheddings

• Compete with other detritivores for decaying resources

UK distribution and where to find them

Several common UK millipede species are widespread across England, Wales, Scotland, and Ireland, though their distribution often reflects habitat availability rather than climate alone.

General distribution patterns:

• White legged snake millipede: common throughout lowland Britain, scarcer in upland areas

• Flat backed millipedes: widespread in woodland across the UK

• Striped millipede: particularly associated with sandy soils and grassland

• Many species more numerous in southern and central England where woodlands are extensive

Habitat-specific distribution:

• Woodland species are more frequent in areas with mature trees and deep leaf litter

• Grassland species like the striped millipede favour meadows, field margins, and coastal dunes

• Urban populations often concentrated in parks, gardens, and allotments with suitable cover

Finding millipedes in the field:

• Turn over stones, logs, and flowerpots in gardens (replace them carefully afterwards)

• Check compost heaps, particularly around the edges where material is moist

• Gently sift through damp leaf litter on woodland walks

• Look under loose bark on dead or dying trees

• Search rockeries and shaded borders after rain

Recording and surveys:

• Conservation organisations run surveys encouraging public submissions

• Sighting records help improve millipede distribution maps for Britain and Ireland

• Local biological records centres welcome observations with photographs

How to support millipedes in UK gardens

UK gardens, allotments, and urban green spaces collectively provide substantial habitat for invertebrates. With simple changes, you can make your garden more welcoming for millipedes, UK isopods kept as pets or for education, and the wider decomposer community.

Wildlife-friendly practices:

• Leave some leaf litter and dead wood in corners rather than clearing everything away

• Maintain a compost heap—this provides ideal millipede habitat and feeding grounds

• Avoid excessive digging of every bed to preserve soil structure and microhabitats

• Create log piles in shaded spots as refuges for numerous invertebrates, including those interested in keeping different species of isopods

Reducing chemical use:

• Minimise or eliminate pesticide use where possible

• Chemicals can harm millipedes directly or disrupt the fungi and microorganisms they feed on

• Slug pellets and broad-spectrum insecticides are particularly damaging, and unnecessary if you encourage natural predators and source animals responsibly from top invertebrate suppliers in the UK

Habitat enhancement:

• Plant native shrubs and trees to create shade and maintain moisture

• Allow ground cover plants to establish in borders

• Position rocks or stones to create cool, damp hiding spots

• Sustain the conditions millipedes prefer—cool, damp, and sheltered

Benefits for your garden:

• Encouraging millipedes and other detritivores improves soil health naturally

• Better nutrient cycling leads to improved fertility over time

• Healthy decomposer communities reduce the need for synthetic fertilisers, and any purchase of live invertebrates to boost these communities should be backed by clear terms and conditions for buying livestock online

• Supporting these threatened-by-tidiness creatures benefits the whole garden ecosystem

By creating millipede-friendly spaces, you’re supporting a network of decomposers that quietly maintain soil health beneath your feet. Next time you lift a log or turn your compost, take a moment to appreciate these slow moving creatures going about their essential work.