Description: A heart-shaped sea urchin with an indentation at the front of the test. The fasciole on the upper side encircles all five petals of the ambulacra and is conspicuous in the living animal. It is characteristically lyre-shaped hence the specific name. About 5cm in length.

Habitat: A characteristic species of fine muddy sand, occurring in large numbers in suitable habitats with Amphiura chiajei. May be commoner in deep water, in Scottish sea lochs it is often associated with Funiculina quadrangularis. Found in depths of 5-365 metres.

Distribution: Known from the west, north and east coasts of the British Isles but not recorded from the south coast.

Similar Species: The only heart urchin likely to be found in muddy sediments.

Key Identification Features:

• Heart-shaped test with the anterior ambulacrum indented.
• Lyre-shaped peripetalous fasciole.

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

iNaturalist: Brissopsis lyrifera at iNaturalist World Species Observations database.

WoRMS: Brissopsis lyrifera at World Register of Marine Species. Accepted name: Brissopsis lyrifera (Forbes, 1841). AphiaID: 124373.

Classification: Biota; Animalia; Echinodermata; Echinozoa; Echinoidea; Euechinoidea; Irregularia; Atelostomata; Spatangoida; Brissidina; Brissidae; Brissopsinae; Brissopsis