Armadillidium hauseni 'Triceratops' Isopods

The first thing you notice is the horn. Armadillidium hauseni carries a prominent, shield-like tubercle on the head, a raised projection that gives this Greek pill woodlouse its 'Triceratops' nickname and marks it out from every smooth-headed Armadillidium in the trade. It is an odd, striking feature, and it is what draws most keepers to the species in the first place.

Behind the horn, the body carries the same theme. It is heavily granulated and armoured, with a rugged, prehistoric texture that reads more like a small trilobite than the rounded isopods most people picture. The colouring is muted, greys and browns rather than bright pigment, so the appeal here is shape and texture rather than colour. Adults reach roughly 12 to 18 mm, mid-sized for the genus, and typically live two to three years. They move at a measured, unhurried pace and rarely rush for the exit when the lid comes off, which makes them easy to sit and watch.

The species is endemic to Greece, one of a small but growing group of Greek Armadillidium in captive culture, and a relatively recent, scarce arrival to the UK. Most cultured species in the genus come from Croatia, Italy or France, so a Greek animal is a real geographic novelty. Care follows the classic Armadillidium pattern, which is forgiving once you understand it. As a Mediterranean pill woodlouse it wants a moisture gradient rather than a wet box, so keep one corner damp with lightly misted sphagnum and let the rest dry out between waterings, aiming for somewhere around 50 to 70 per cent overall. These animals evolved in country that dries between rains, and constant damp will stress them, so give the enclosure medium ventilation and good cross-flow.

A free-draining substrate suits them. I would start with a base of flake soil, topped with a generous layer of magnolia leaf litter and other hardwood leaves, which serve as cover and as the foundation of the diet. They are detritivores, grazing the leaf litter, rotting wood and substrate for most of what they need, with the occasional vegetable such as courgette or carrot and a little protein now and then, though far less protein than a Porcellio wants. Calcium matters more here than with many isopods, both for clean moults and because Greek Armadillidium are hungry for it, so keep cuttlefish bone, crushed limestone or oyster shell available throughout.

Room temperature suits them, roughly 18 to 26°C, with no extra heating needed in most heated homes. Like every true pill woodlouse, hauseni conglobates, rolling into a tight sealed ball when startled rather than bolting. Breeding is steady rather than prolific: females carry their young in a brood pouch and release tiny replicas of the adults, horned heads and all, though a fresh colony can take several months to settle before you see much of it.

Once settled, hauseni is hardy and undemanding, and a distinctive collector's Armadillidium for anyone building beyond the common species. It sits happily beside patterned Mediterranean forms like the Clown, or as a textural counterpoint to brighter morphs such as Pallasii Orange and Magic Potion. You will find it in the wider Armadillidium collection alongside the rest of the genus.

Every order is captive-bred, boxed double-walled around a ventilated tub of damp sphagnum and sent out Monday to Thursday by tracked next-day Royal Mail, with a live-arrival guarantee and a 20% overcount included as standard.