Moo Cow Isopods (Porcellio scaber)

The Moo Cow is one of the modern hobby's home-grown success stories: a striking pied morph of the common Rough Woodlouse, Porcellio scaber, first developed here in the UK by Mark Titterton of Isopods Online, who line-bred it from grey Tunisian stock until the cow-spot pattern bred true. The result is a white-bodied woodlouse splashed with bold black flecking, so every animal really does look like a Friesian seen from above, and no two wear the same markings. From those UK culture rooms it has spread across the domestic and international scene on its own merits, which is a rare thing for a British-bred isopod.

It is worth being clear about what it is, because two different "cow" isopods do the rounds. The Dairy Cow is a black-and-white morph of the smooth, larger Porcellio laevis; the Moo Cow is the rougher, slightly smaller P. scaber, the very woodlouse you turn up under half the plant pots in Britain. Both are cow-patterned, but they are different species with a different shell texture, and the Moo Cow sits among the scaber morphs like the mixed Scaber Mix rather than with the laevis crowd.

What makes it such an easy recommendation is that the designer looks come attached to a bulletproof animal. P. scaber is about as hardy and forgiving as isopods get, so the Moo Cow is one of the best first colonies you can buy: striking enough to be satisfying, tough enough that almost anyone can succeed. Adults reach around 18 mm, they are active and often out day and night, and they breed prolifically once settled. Like all Porcellio they do not roll into a ball; startle them and they flatten and sprint for cover instead, relying on speed rather than armour.

Housing is simple. A six to ten litre tub with a clip-lock lid and cross-ventilation on both sides suits a starter group, kept at a moderate humidity with a gradient, around 50 to 70%, rather than uniformly wet: one damp corner, the rest drier, with good airflow to keep mould down. Normal room temperature, roughly 18 to 26°C, works the year round with no heating. Give them a living base of flake soil, rotted hardwood and organic topsoil at least five centimetres deep; a plain coco-coir base is best avoided, holding water while feeding nothing. Top it with magnolia and oak leaf litter, cork bark for cover, and a permanent calcium source such as cuttlebone or crushed eggshell for clean moults.

One feeding point matters more than any other with Porcellio: they are protein-hungry. Leaf litter and rotting wood are the base, but keep a protein source going, fish flake, dried shrimp or a proper isopod protein, a couple of times a week, alongside soft veg like courgette and squash. An underfed, fast-breeding colony can start on its own softer, freshly moulted members, so treat protein as part of the setup, not an afterthought. Do that and they are tireless, tidy workers.

Breeding needs little encouragement: a settled group given warmth, food and calcium will carry young in the brood pouch and drop live miniatures in quick succession, the cow pattern coming through as they grow. For a deeper look at the group, our guide to the different types of Porcellio is worth a read, or browse the full Porcellio collection. A springtail culture alongside keeps mould in check around the protein feedings. Every order is captive-bred here in the UK, sent in a double-walled box around a ventilated tub of damp sphagnum, posted Monday to Thursday by tracked next-day Royal Mail with a small overcount and a live-arrival guarantee.