Description: A large brittle star which lives in coarse gravel and extends a group of long arms up into the water. The arms are banded with dark and pale brown and have long tube feet. The arm spines are flattened and arranged in groups of 11-12 at each joint. There are one long and one small tentacle scale at the edge of each tentacle pore, the long ones tend to cross on the underside of the arm like a pair of swords. Disc 14mm., arms 10x disc diameter.

Habitat: This species has strict habitat requirements, living only in coarse gravel. It is inconspicuous despite its size, and quickly retracts into the gravel on disturbance. May be found with Echinocardium flavescens.

Distribution: A southern species which occurs on the south coast of England, the west coast of Ireland and in SW Scotland as far north as Oban. Its habitat is rarely sampled adequately and it could be much less rare than is supposed. Further distribution south to the Mediterranean.

Similar Species: Ophiopsila aranea is considered to be difficult to separate from this species but has fewer arm spines per joint (6-8).

Key Identification Features:

• Long banded arms protruding from gravel.
• 11-12 long flattened arm spines.
• Large crossed tentacle scales.

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

iNaturalist: Ophiopsila annulosa at iNaturalist World Species Observations database.

WoRMS: Ophiopsila annulosa at World Register of Marine Species. Accepted name: Ophiopsila annulosa (M. Sars, 1859). AphiaID: 125048.

Classification: Biota; Animalia; Echinodermata; Asterozoa; Ophiuroidea; Myophiuroida; Metophiurida; Ophintegrida; Amphilepidida; Ophiopsilina; Ophiopsiloidea; Ophiopsilidae; Ophiopsila