African Giant Black Millipede (Archispirostreptus gigas)

Archispirostreptus gigas, the African Giant Black Millipede, is the largest millipede on Earth. A full-grown adult stretches to around 33cm and some 67mm in circumference, as thick as a courgette and carrying somewhere near 256 legs, and for all that scale it is one of the calmest animals I keep. This is the millipede you can actually hold. Across southern Africa it is known as the Shongololo, and it has spent decades as the gentle face of the millipede hobby in zoos and classrooms the world over.

What surprises most people is how easy-going it is. A settled gigas walks slowly across an open palm, exploring rather than bolting, and it neither bites nor stings. Its first defence is to coil into a tight spiral and show the hard shell of its back, and I do mean coil, because this animal winds up like a watch spring rather than rolling into a ball. If it ever feels cornered it can weep a defensive fluid from the pores along its body. Wood analysed this species directly in 1974 and found toluquinone and methoxy-methylbenzoquinone: it stains skin brown, irritates it if it is left on, and burns an eye badly enough to need treating. I wash my hands with soap afterwards and suggest you do the same before you touch your face. Watch that children do too, because they account for almost every eye injury on record. Beyond that it is about as beginner-friendly as a large invertebrate gets, and it can share the better part of a decade with you, seven to ten years being normal in good care.

I would rather be straight with you about what you are buying. These adults are wild imports, as the vast majority of gigas in the hobby are. They breed slowly and take years to reach this size, so home-grown adults are scarce everywhere, not just here. The honest upside is a long, well-earned track record. Wild-caught gigas settle beautifully into a stable enclosure and go on to live for years once they are comfortable.

Their care hangs almost entirely on the substrate, because for this species the substrate is the food. Give them a deep bed, 15 to 20cm at the least, of rotting hardwood and decaying leaf litter that they can burrow down into and eat their way through. A base of flake soil topped with plenty of magnolia leaf litter covers most of what they need, and I refresh the leaves as they work through them. Calcium matters just as much for an animal building an exoskeleton this size, so keep a cuttlebone or a piece of limestone in there at all times.

They want it warm and humid, around 22 to 26°C, with the substrate kept damp like a wrung-out sponge. Two rules are worth stating plainly. Never heat from underneath, because these are burrowing animals and a base heat source is fatal to something that digs down to escape the warmth. And never use softwood or pine, whose resins are toxic to millipedes, so keep it to hardwoods only. Warm the side of the enclosure if a British winter calls for it, and let the deep substrate hold the humidity for you.

If the Shongololo draws you in, there is a wider world to explore. The Ivory Millipede is a paler, striking contrast, the African Giant Chocolate is another substantial African species with a warm brown finish, and the Hawaiian Glow brings a quieter, luminous charm to a shelf. Any of them will happily share the same style of deep, wooded setup.

Whichever you choose, your millipede travels safely. I pack each one in a double-walled box around damp sphagnum moss and post Monday to Thursday only, by tracked next-day Royal Mail and backed by a live-arrival guarantee, so it reaches you settled and in good order.