Description: The largest scallop found in Britain or Ireland, growing up to 15 cm. It is reddish-pink, off-white or light brown in colour. Shells (valves) are unequal - uppermost valve is convex while lower valve is flat. Each shell is strongly ribbed, with around 16 distinct ridges.

Habitat: Sand, fine gravel or sandy mud to depths of up to 100 m.

Ecology: When very young they are usually attached by byssus, with older individuals free living. Can swim, but not an active swimmer like Aequipecten opercularis.

Distribution: Found all around Britain and Ireland.

Similar Species: Unlikely to be confused with any other species.

Key Identification Features:

• Large scallop, up to 15 cm.
• Unequal valves, uppermost convex, lower flat.
• Strongly ribbed, with around 16 distinct ridges on each shell/valve.

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

iNaturalist: Pecten maximus at iNaturalist World Species Observations database.

WoRMS: Pecten maximus at World Register of Marine Species.