Trachelipus caucasius Isopods

Most of the isopods in this hobby want steady warmth, so a species that shrugs off a cold room is a useful thing to have, and that is Trachelipus caucasius's trick. It comes from the Caucasus and the Black Sea coasts of Russia, Georgia and Turkey, a region of warm summers and hard winters, and it has brought that broad tolerance with it. Where a tropical species would sulk or stall in an unheated spare room, caucasius keeps going, which makes it one of the easier larger isopods to keep in a normal, occasionally chilly British house.

It is a substantial animal, too. A large Trachelipus, reaching up to around 3 cm, it is grey with a warm orange or amber edging picked out along the segment margins, and the segmented, slightly flattened body gives it a low, armoured, faintly prehistoric look. It is easy to observe and makes a solid display animal, more understated than the bright Mediterranean morphs but handsome in a naturalistic way. It shares the flattened build of its better-known genus-mate the Trilobite, though caucasius runs larger.

Like all Trachelipus it cannot pull the full pill-bug trick. Faced with trouble it stays flat and relies on speed and cover rather than rolling into a sealed ball the way an Armadillidium does. That is simply how the genus is built, not a shortcoming, and it puts caucasius in the same bracket as its relatives the neat difficilis and the flat, dry-country Coros rather than with the rollers.

Housing is undemanding. A five to ten litre tub with a clip-lock lid and cross-ventilation on opposite walls suits a starter colony. Keep a moderate humidity with a gradient, around 55 to 70%: a damp corner under sphagnum and leaf litter with the rest allowed to breathe and dry between mistings. The temperature range is the easy part, anywhere from cool room conditions up to the mid-20s in Celsius, and it will sit happily at the lower end that would trouble a tropical species. Give them a living base of flake soil, rotted hardwood and organic topsoil around five centimetres deep, and keep a plain coco-coir base out of it, since it holds moisture but offers nothing to graze.

Top the substrate with a generous layer of magnolia and oak leaf litter and cork bark for cover, and leave a calcium source such as cuttlebone or crushed eggshell in permanently for clean moults. Feeding is the standard detritivore spread: leaf litter and rotting wood always available, soft veg like courgette, carrot and squash a couple of times a week with leftovers lifted out promptly, and an occasional pinch of protein such as fish flake or dried insects to keep a breeding colony productive.

Breeding is reliable once a colony settles, the female carrying young in her pouch and releasing live miniatures, and a starter group given warmth, calcium and steady food builds into a self-sustaining population over a season or two. A springtail culture alongside keeps mould in check around damp corners and protein scraps, and the two coexist without any bother. Every order travels as an established colony in a double-walled box around a ventilated tub of damp sphagnum, posted Monday to Thursday by tracked Royal Mail aiming for next-day delivery, packed with care and covered by our live-arrival guarantee.