Porcellionides pruinosus 'Wild Type' Isopods

Blink and you will miss it. Porcellionides pruinosus, the Tropical Grey Woodlouse, is quicksilver on legs: a restless, plain grey animal, 12 to 15 mm long, that scurries across the substrate at a speed most isopods never manage. It is diurnal and rarely hidden, out in the open far more than the shy rollers people expect. And for all its plainness, this is the original, the wild grey stock from which every flashy Powder morph on the shelves was bred. Watch the tub for a minute and something is always moving.

The 'Wild Type Powdered' is the natural, unaltered form of the species, and the foundation behind the whole Powder line: Powder Blue, Powder Orange and Powder White all trace back to this animal. The body is a purplish grey, with long whitish legs and pale-banded antennae, and it carries the faint pale bloom that gives the family its name. That "powder", a pruinose dusting over the shell, is the Porcellionides signature, and it catches the light nicely between moults. Grey, yes, but far from dull.

Unlike the pill woodlice, this one cannot roll into a ball. It is flat-bodied and does not conglobate at all, and its whole defence is speed. Disturb the colony and they scatter rather than tuck away, which is part of what makes them such lively animals to watch. They are decent climbers too, so a secure, well-fitting lid matters more here than with slower species. They are not shy, and they are not fragile.

Care is straightforward, and forgiving. For all the "tropical" in its common name, this is a Mediterranean animal of compost heaps, manure and stable bedding, a fast detritivore of warm, well-aired waste, and that ecology tells you what it wants. These are extremely hardy woodlice that need good ventilation and a moderate moisture gradient rather than a wet box. Keep one end damp and let the rest run drier so the colony can choose, with cross-ventilation on opposite sides to stop the substrate stagnating. Room temperature suits them, and they breed fastest at the warmer end of a normally heated home.

Give them a living base rather than a plain coco-coir fill. I build the substrate from flake soil, rotted hardwood and organic topsoil, 4 to 6 cm deep, so it feeds the colony as much as it houses them. A generous top layer of magnolia leaf litter with a few pieces of bark gives cover and grazing. They also like some protein alongside the leaf litter, a pinch of fish flake or dried shrimp now and then, which keeps their heavy breeding ticking over.

Prolific barely covers it. A single female can produce around 400 young over her life, and a settled colony builds fast, which is why this is one of the best bioactive clean-up crews going. The young arrive as live, fully formed miniatures, carried first in the mother's brood pouch, and they grow quickly. They tear through waste and mould, and make a productive feeder colony too. If you want a smaller, quieter crew for a planted vivarium floor, the Dwarf White is the gentler choice, while the Wild Type is the faster, bolder, more visible worker.

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