Hallaniyat Island 'Oman' Isopods (Periscyphis sp)

Al-Hallaniyah is a barren granite island in the Arabian Sea, the largest of the Khuriya Muriya group off the Dhofar coast of Oman. Vegetation there is close to absent, the peaks run to around 500m, and roughly 94mm of rain falls in a year with none at all between June and September. The isopod collected there lives on and under the rocks. Build the enclosure around that sentence and you will keep it. Build it like a normal isopod tub and you will not.

Keep it dry

This is the inversion that catches people. Almost every isopod in the hobby wants damp substrate and a moisture gradient on top of it. This one wants the opposite: the enclosure kept as dry as you can manage, with a single small corner held permanently moist under a pad of moss and nothing else wetted at all. The two independent European keepers who have written the animal up both say the same thing in nearly the same words, and both arrived at it separately.

It also wants heat, which is the second departure. A British room is too cool. Aim for the middle twenties, around 24 to 27°C, with a low-wattage mat against one side wall rather than beneath the box, so the animals have a thermal gradient to work with. Below about 25°C they stop being active altogether. Substrate is roughly half forest soil and half sand, pressed into the gaps between fist-sized limestone rocks, which is as close to the island as you are going to get in a box.

What it is

Periscyphis was erected by Gerstaecker in 1873 and sits in the family Eubelidae, a group that barely exists in the hobby at all. Around forty-five to fifty species are described, and the genus is strictly African and southern Arabian, with several species named from Oman including one from Dhofar on the mainland opposite these islands. Nobody has matched the animal in the trade to any of them, so it goes out as Periscyphis sp. and stays that way until someone does the work.

Adults are small, somewhere between 13 and 17mm depending on whose count you read. Eubelidae are a conglobating family, so expect it to roll, though I have not seen that stated anywhere for this species specifically. They are nocturnal and sit in groups. Colour is the one thing I will not describe secondhand, because no published account of this animal describes it at all. Look at the photographs.

Who it suits

Advanced keepers, and only those who want the challenge rather than the animal. It grows slowly, it breeds slowly, and a dry warm enclosure is a fussier thing to hold steady than a damp one. There is no margin in it for someone still learning. Feed decaying wood, beech and oak leaf litter, cuttlebone always available, and small amounts of courgette, carrot or sweet potato.

Barely a word has been published on this isopod in any language. What exists is one German keeping report from a collector who went to the island, plus a handful of European listings, and that is the whole record. Where this page states a figure it comes from those, and where it does not state one it is because nobody knows. Everything else we stock sits in our isopod range, and if this is your first colony, the beginner list is the better place to begin.

Cultures travel over moistened moss, shut into a vented pot which is then bedded inside an outer carton of doubled walls. We stop posting on Thursdays so no order of ours is stranded across a Sunday. Carriage is tracked and next-day, arriving before 1pm. Every count leaves with a few spares folded in, and live arrival is guaranteed.