Description: A large brittle star with moderately long arms and a smooth disc. The arm spines are prominent and neatly arranged like the teeth on a comb. The characteristic colour is almost uniform dark brown or black but pale, almost white specimens occur in any population. There are five to seven long slender arm spines and a pair of tentacle scales. Disc 25mm., arms 5x disc diameter.

Habitat: Usually found in moderately sheltered sites with some water movement, may form dense beds with over 100 animals to the square metre, often associated with Ophiothrix fragilis. Lives out in the open on boulders, bedrock or gravel. Tolerant of brackish conditions.

Distribution: Common all round the British Isles apart from the southern North Sea.

Key Identification Features:

• Large smooth disc, usually dark brown or black in colour.
• Robust arms with neat arm spines.

Distribution Map from NBN: Ophiocomina nigra at National Biodiversity Network mapping facility, data for UK.

iNaturalist: Ophiocomina nigra at iNaturalist World Species Observations database.

WoRMS: Ophiocomina nigra at World Register of Marine Species. Accepted name: Ophiocomina nigra (Abildgaard in O.F. Müller, 1789). AphiaID: 125027.

Classification: Biota; Animalia; Echinodermata; Asterozoa; Ophiuroidea; Myophiuroida; Metophiurida; Ophintegrida; Ophiacanthida; Ophiacanthina; Ophiotomidae; Ophiocomina