Giant African millipede

Archispirostreptus gigas · Round-backed millipedes

One of the largest millipedes in the world, a slow-moving, non-venomous detritivore that feeds on decaying plant material and is commonly kept as a pet.

!To humansIrritant secretions ❦To plantsBeneficial
Giant African millipede (Archispirostreptus gigas)
(c) Stephanie Dolrenry, some rights reserved (CC BY-SA) · iNaturalist

!Is the giant African millipede dangerous?

Only mildly. Not venomous and do not bite as a defense. When stressed they can release a defensive fluid that may irritate skin or eyes and can stain clothing. Wash skin with soap and water if contact occurs; avoid touching your eyes after handling; rinse eyes with plenty of clean water and seek medical attention if irritation is severe or persistent.

Pets

Generally not dangerous to pets but secretions can irritate pet skin or mucous membranes; small pets that chew or eat millipedes may become sick and should be monitored or seen by a vet if they show signs of distress.

📖Overview

Archispirostreptus gigas is a large, slow-moving millipede native to parts of East Africa. It feeds on decaying leaves, wood and other plant matter and plays an important role in nutrient recycling. Adults can reach substantial lengths and are popular in the pet trade and classroom displays because they are easy to handle when calm.

These millipedes are primarily nocturnal or crepuscular and spend daylight hours hidden under logs, leaf litter or in burrows. When disturbed they curl into a tight spiral to protect their softer underside and may release a defensive fluid that can irritate skin or eyes. They are not venomous and do not bite in the way predatory arthropods do.

🔍How to identify a giant African millipede

Adults are cylindrical, composed of many body segments each with two pairs of legs, giving a dense banded appearance. Colour varies from dark brown to black or reddish-brown, often with a glossy, slightly striated exoskeleton. When threatened they roll into a coil exposing the harder dorsal plates. Males are generally smaller and slimmer than females; females can appear stouter particularly when gravid.

  1. Very large cylindrical body up to about 20-38 cm long with many segments.
  2. Each body segment bears two pairs of legs, producing a dense, banded-looking underside.
  3. Glossy dark brown to black or reddish-brown dorsal plates; curls into a tight spiral when disturbed.
  4. Slower moving than centipedes and lacks the flattened, fast-bodied appearance and visible long legs of centipedes.

Lookalikes

American giant millipede Narceus americanus

Also a dark, round-backed millipede that coils when disturbed, but much smaller (up to about 10 cm), often with reddish edges to the segments, and native to eastern North America.

Giant African millipede vs American giant millipede →

Other spirostreptid millipedes Spirostreptidae (various species)

Related large round-backed millipedes may look similar; A. gigas is among the largest and has a robust cylindrical body and specific regional range.

↻Life cycle

  1. Egg

    Females lay clusters of eggs in moist soil or rotting wood; incubation time varies with temperature and humidity.

  2. Juvenile (nymph)

    Hatchlings resemble small adults but with fewer segments and legs; they grow by molting and add segments at each molt.

  3. Adult

    After multiple molts juveniles reach adult size and reproductive maturity; adults continue to molt periodically.

🍃Diet and predators

Young eat

Decaying plant material, leaf litter, rotting wood; juveniles may accept softer fruits in captivity

Adults eat

Detritivore; primarily dead leaves, decaying wood and other decomposing vegetation; may also consume soft fruits and vegetable scraps in captivity

Predators of the young

Birds, small mammals, amphibians, reptiles and predatory insects

Predators of adults

Larger birds, small mammals, some reptiles and invertebrate predators; curling and chemical defenses reduce predation

🌱Effect on plants and gardens

Feeds on dead and decaying plant material; helps break down leaf litter and return nutrients to the soil. Not a primary pest of live crops or healthy plants.

📍Where and when to find it

Look under logs, rocks, leaf litter, rotting wood and in soil crevices. In captivity they are often found in the moist substrate of their enclosure.

Best time

Night and early evening are best for observing them; active year-round in warm climates.

Observation tips

Use a soft light and approach slowly. Photograph from above or at slight angle to show the cylindrical body and leg pairs. Keep them moist and minimize handling stress if observing in captivity.

✨Fun facts

  • Giant African millipedes can live many years in captivity, sometimes 5-10 years with good care.
  • They have two pairs of legs per body segment — that is a defining trait of millipedes (Diplopoda).
  • Instead of venom or a bite, their main defense is curling up and using a chemical secretion that can deter predators.

?Frequently asked questions

Do giant African millipedes bite?

No. They are detritivores with chewing mouthparts for eating decaying plant matter and are not aggressive biters.

Do giant African millipedes spray acid or poison?

They secrete a defensive fluid that can irritate skin or eyes and may have a noticeable smell. It is not delivered as a spray or venomous bite. Avoid handling them with bare hands if you are concerned; wash hands after handling.

Why is a giant African millipede in my house?

They are attracted to damp, dark places and decaying organic matter. They may wander indoors seeking moisture or shelter, especially during wet weather.

How do I get rid of giant African millipedes in my home?

Gently pick them up (use gloves) and release them outdoors away from the house. Reduce moisture, seal entry points, remove leaf litter and woodpiles near foundations to make your home less attractive to them.

Are giant African millipedes good for my garden?

Yes. They are beneficial decomposers that help break down organic matter and return nutrients to the soil; they rarely damage healthy plants.

This guide was written with AI assistance and fact-checked, last updated 2026-10-10. Identification from photos is never certain: don't handle insects you can't identify, and get medical advice for bites, stings or allergic reactions. More about the giant African millipede: iNaturalist, Wikipedia.