General Information

What are millipedes?

Millipedes belong to the class Diplopoda, a name meaning "double foot", because each body segment carries two pairs of legs rather than one. They are among the oldest land animals on Earth, with a fossil record stretching back over 400 million years.

Despite the name, millipedes do not actually have 1,000 legs. Most species have between 30 and 400 legs depending on their size and number of segments. The record holder is now Eumillipes persephone, discovered in 2021 in Australia, with 1,306 legs, the first millipede confirmed to exceed 1,000 legs. (Illacme plenipes, a tiny Californian species with up to 750 legs, held the previous record.)

There are approximately 12,000 described species of millipede worldwide, ranging from a few millimetres to over 30 cm in length. They are found on every continent except Antarctica.

Millipedes vs centipedes

This is one of the most common questions we get. Despite looking vaguely similar, millipedes and centipedes are very different animals:

• Legs per segment: Millipedes have two pairs of legs per body segment; centipedes have one pair per segment.
• Speed: Where millipedes are slow and deliberate, centipedes are fast and agile predators.
• Diet: Millipedes are primarily detritivores, though some species are facultative scavengers and will consume animal protein such as dead insects or carrion. By contrast, centipedes are active predators that hunt insects and other invertebrates.
• Defence: When threatened, millipedes curl into a tight coil and may release chemical secretions. Centipedes instead defend themselves by biting with venomous forcipules.
• Temperament: Handling millipedes is safe and easy. Centipedes are aggressive, fast, and can deliver a painful bite.

Defensive secretions

Many millipede species produce chemical secretions as a defence mechanism. These commonly include benzoquinones and, in some species (particularly the order Polydesmida), hydrogen cyanide. The secretions can stain skin and irritate eyes and mucous membranes. Always wash your hands thoroughly after handling millipedes, and avoid touching your face during handling.

Ecological role

Millipedes are major decomposers in forest and woodland ecosystems. They break down leaf litter, dead wood, and other decaying organic matter, returning nutrients to the soil. Their burrowing also aerates the substrate, benefiting plant growth. In many habitats, they are some of the main decomposers in many forests.

Why keep millipedes?

Millipedes make excellent pets for keepers of all experience levels. They are docile, tolerate gentle handling well, and pose no serious danger to humans, though some species produce defensive secretions that can stain skin and irritate eyes (see above). The giant African millipedes in particular reach sizes of over 30 cm, and they make great display animals. Their behaviour is more interesting to watch than you'd expect. They graze, dig around, and bump into each other constantly.

Common issues to be aware of

Mite infestations: Small white mites are extremely common in millipede enclosures. In most cases these are harmless grain mites that thrive in the same warm, humid conditions your millipedes need. They should be monitored. If numbers increase dramatically, review your feeding and remove uneaten fresh food promptly. A small population of grain mites is usually nothing to worry about.

Toxic substrates: Never use cedar or pine substrates (shavings, chips, or bark) in a millipede enclosure. The aromatic oils in softwoods are toxic to millipedes and can be fatal. Stick to deciduous hardwood, coco coir, and organic topsoil.

Breeding expectations: Most large millipede species breed very slowly in captivity. Eggs can take months to hatch, and young grow at a glacial pace. It may take several years for offspring to reach adult size. If you are hoping to breed, be prepared for a long wait.

Care basics at a glance

• Enclosure: Minimum 60x40x40 cm for large species such as Archispirostreptus gigas. Smaller species require proportionally smaller enclosures. Glass terrariums or ventilated plastic boxes work well. Moderate ventilation. Avoid fully mesh lids that dry the enclosure out.
• Substrate: Deep (10–20 cm depending on species size), moist, nutrient-rich mix: 50% well-rotted deciduous wood, 30% coco coir, 20% organic topsoil or leaf mould. Dried leaves on top. Larger species like A. gigas need the deeper end (20 cm). Never let it dry out.
• Temperature: 22–26°C for most species.
• Humidity: 70–80% suits most tropical species. The notable exception is Orthoporus ornatus (desert millipede), which needs only 40–60%. See its species guide for details. Mist regularly. Substrate should feel like a wrung-out sponge.
• Food: Rotted wood and dried leaves (staple), supplemented with vegetables (cucumber, courgette, sweet potato), mushrooms, and cuttlefish bone for calcium.
• Handling: Support the full body, let them walk hand to hand, never grip. Wash hands after handling.