Eluma purpurescens Budde-Lund, 1885
GB rarity status: Naturalised
This large pill-woodlouse (to 15mm) is virtually identical to Armadillidium vulgare in size and shape and is able to roll into a perfect sphere. It is easily distinguished from all Armadillidium spp. by possessing eyes composed of single prominent ommatidium.
Distribution and Habitat
It is mainly found across the extreme south-east of England, but outlying populations occur elsewhere, notably Co. Dublin, Ireland and Cumberland coast, northern England. It favours disturbed habitats, whether this is on the coast (e.g. ‘soft’ slumping cliffs) or synanthropic habitats (e.g. waste ground, railway lines and gardens).
It typically takes refuge under mat-forming plants, beneath stones and dead wood, or among leaf-litter, tussocks, rubbish and other debris.
This summary is based on the detailed account in Gregory (2009).