Sphaerechinus granularis (Lamarck, 1816)

Sphaerechinus granularis

Description: A robust-looking regular sea-urchin. The test is somewhat flattened compared with Echinus and the spines are much thicker and very blunt. There are two distinct colour forms, purple all over and purple with white spines. The spines are very regular in size and arrangement giving a neat overall appearance. Up to 15cm. in diameter.

Habitat: Mostly in fairly shallow water, to 30m or slightly more. Found in sheltered or semi-sheltered conditions amongst algae on rocky and gravel sea-beds. Often covers itself with loose algae.

Distribution: Only found to the south of the English Channel, where it has been reported from the Channel Islands and is quite common in the Bay of Morlaix. Further distribution south to the Mediterranean and Cape Verde.

Similar Species: This is a large urchin, comparable in size with Echinus esculentus, from which it is easily distinguished by the thick, neatly-arranged, spines.

Key Identification Features:

• Large, flattened test
• Thick, blunt spines, all of one size
• Purple test with purple or white spines

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