Echinocardium cordatum (Pennant, 1777)

Echinocardium cordatum

Description: A heart-shaped sea urchin which burrows in clean sand. The test is truly heart-shaped with a definite indentation in the broader end, corresponding with the sunken frontal ambulacrum. In Echinocardium species there is an inner fasciole surrounding the frontal ambulacrum and the apical plates. Up to 9cm in length.

Habitat: Lives buried in clean sand at a depth of 10-15cm. There is usually a conical depression at the surface corresponding with the position of the animal. Food in the form of detritus collects in this depression and is passed down to the buried animal by the long tube-feet of the frontal ambulacrum.

Distribution: Very common all round the British Isles from low tide mark to moderate depths.

Similar Species: Similar to other Echinocardium species but distinguished by the depressed frontal ambulacrum.

Key Identification Features:

• Heart-shaped test with indentation at front.
• Habitat in clean sand.

Distribution Map: NBN map : National Biodiversity Network mapping facility, data for UK.

WoRMS: Species record : World Register of Marine Species.

iNaturalist: Species account : iNaturalist World Species Observations database