Portuguese Millipede

Fascinating facts about the Portuguese Millipede

• In 1953, a shipping container from Portugal landed in Western Australia carrying a stowaway no one was looking for: millipedes. Seventy years later, Ommatoiulus moreleti has colonized over 300,000 square kilometres of Australian farmland — an area larger than New Zealand. With no natural predators waiting in their new home, they've turned entire wheat and barley crops into dust. The insect equivalent of a biological avalanche, released by accident.
• A Portuguese millipede's body is a chemical factory. When threatened, it sprays hydrogen cyanide — the same poison used in lethal injections — directly from 200 paired glands running down its flanks. The smell alone stops most predators. Back in the Mediterranean, native wasps evolved to tolerate it. In Australia, nothing did.
• These millipedes move through soil in armies. A single female lays 300 eggs in a season, and the juveniles stay together in clusters so dense they create visible moving carpets across paddocks at dusk. Farmers have watched entire hillsides turn black with migrating millipedes, a phenomenon first documented in the 1960s that still happens every autumn. The sheer number turns a tiny creature into a geological event.
• A Portuguese millipede is 30 millimetres long and has 200 legs — two pairs per segment, all of them synchronised in a hypnotic wave that pushes them through decaying plant matter faster than any other millipede species. This speed, combined with their appetite for decomposing crops and roots, means they can strip a season's growth in days. They're not eating plants; they're eating Australia's agricultural timeline.
• When millipedes die in water troughs and on roads, they release cyanide into the environment. Dead specimens have been documented poisoning sheep that drank from contaminated troughs. In Australia's driest regions, this millipede has become a hidden cost of drought — an invader that created a second crisis nobody can see, turning a decomposer into a threat to the food chain itself.

At a glance

About the Portuguese Millipede

In the damp, moss-softened crevices of ancient stone walls, the Portuguese Millipede weaves its subtle path, a whispered rustle of innumerable legs as it navigates the hidden topography of its subterranean realm. With each delicate, segmented wave, it propels itself forward, a mesmerizing embodiment of slow, relentless purpose, driven by the primal urges of survival and exploration. As it moves, the millipede leaves behind a trail of faint, glistening threads, a testament to its quiet industry and the mysterious, unseen world it inhabits.

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