Porcellio hoffmannseggii 'Sevilla' Isopods

Same giant, different city. This is the Sevilla form of the Titan (Porcellio hoffmannseggii), the big Iberian woodlouse that for years sold as its own undescribed species, Porcellio sp. "Sevilla". As of 2024 it has been confirmed as a form of the Titan rather than a species of its own: the same animal, from around Sevilla in southern Spain. Dr Julio Cifuentes, who knows the Spanish Porcellio better than most, identified it as a morphological variant of P. hoffmannseggii, the species Brandt first described in 1833. The trade name has stuck because the look and temperament earn it, but taxonomically this is hoffmannseggii.

It is a large, fast woodlouse, 25 to 35 mm as an adult, which is a lot of isopod. The body is grey to dark grey with a smooth, slightly glossy back and a pale skirt running along the margin, and males carry long uropods at the tail. It cannot conglobate. Where an Armadillidium rolls into a ball when startled, this one flattens, holds still, or runs, relying on size, speed and cover rather than armour. Lift a piece of bark and the colony scatters. That is part of the appeal.

Care comes down to one idea that trips up new keepers: this is a dry animal. I keep mine in a well-ventilated tub with plenty of airflow and a single damp corner, not a humid box. Most of the enclosure stays dry, with one moist patch of sphagnum the colony can visit when it wants to. Low overall humidity, real cross-flow ventilation and a clear dry-to-damp gradient are what keep it thriving. Over-misting and stuffy, stagnant air are the usual reasons a hoffmannseggii colony struggles.

For substrate I use a free-draining base of flake soil, rotted hardwood and topsoil, kept mostly dry, and I would avoid a plain coco-coir base, which holds too much water for this one. A few centimetres is plenty, since it forages on the surface rather than burrowing deep. Top it with a generous layer of hardwood leaf litter, oak, beech and hazel, plus cork bark and chunks of rotting wood for cover and food. Calcium wants to be constant: cuttlebone, crushed oyster shell or limestone left in permanently.

Feeding is simple, with one warning. Porcellio hoffmannseggii is protein-hungry, and a fast colony this size will start nibbling its own moulting members if the protein runs out. So I keep a protein source available at all times, fish flake, dried shrimp or the like, alongside leaf litter, rotting wood and the odd piece of veg such as courgette or squash. Offer protein and fresh food on the dry side to slow spoilage, and do not be alarmed by how quickly an established colony clears a meal.

Temperature is easy: standard room warmth suits it, and breeding picks up towards the warmer end of that range, so there is no need for extra heat in most heated homes. Given calcium, protein and a stable gradient, it breeds prolifically, and a starter group grows into a self-sustaining colony without much fuss. It sits in our wider Porcellio collection alongside the other Iberian giants: the bright hoffmannseggii Orange, the same species in a much louder colour, the Expansus Orange and the Magnificus.

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 small overcount as standard.