Description: This bivalve is an elongate oval shape, with two equal valves. The shell is weak and brittle and has fine concentric lines. It is white in colour but this may be covered in part by a shiny, light brown periostracum. It can reach up to 25 mm in size. Growth stages are not clear in this species. Right valve has two cardinal teeth, and single anterior and posterior lateral teeth. Left valve has one cardinal tooth and weak single anterior and posterior laterals. Pallial sinus is deep.

Habitat: Clean sand, fine sand and sandy mud from low water to around 60 m.

Distribution: Recorded around all coasts of Britain and Ireland.

Similar Species: There are other superficially similar looking bivalves and other species of Abra found in Britain and Ireland. These can be distinguished by the presence (or not) of lateral teeth, the shape of the shell and visibility of growth stages.

Key Identification Features:

• Brittle, weak, white shell, which may be partially covered by glossy, light brown periostracum.
• Grow stages not clear.
• Lateral teeth present.
• Pallial sinus deep.

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

iNaturalist: Abra prismatica at iNaturalist World Species Observations database.

GBIF data for Abra prismatica

WoRMS: Abra prismatica at World Register of Marine Species. Accepted name: Abra prismatica (Montagu, 1808). AphiaID: 141436.

Classification: Biota; Animalia; Mollusca; Bivalvia; Autobranchia; Heteroconchia; Euheterodonta; Imparidentia; Cardiida; Tellinoidea; Semelidae; Abra