A large star with an arm span to about 38 cm (15 in), deep red through purplish, and unusually smooth: the long cylindrical arms carry neither spines nor warts, and the surface has a wet, almost polished look under a torch. The central disc is small for the size of the animal, so the outline is dominated by five clean tapering limbs.
It lives on coral rock and rubble slopes from about 3 m to 30 m (10 to 100 ft), sheltering in crevices by day and emerging after dark to graze the film of algae and detritus over hard surfaces. Color and smoothness together identify it here; nothing else of that size is both this red and this featureless. Like other long-armed stars it can shed a limb under stress and regrow it, but the process takes months and a shed arm is a real cost rather than a party trick. Night dives on rubble slopes are where the species turns up, usually as a single animal draped over rock.
- long smooth cylindrical arms with no spines or warts
- orange with red spots, through to deep red or purplish
- glossy, almost polished surface under a torch
- small disc relative to the arms
- arm span up to 38 cm
