Description: This bivalve has a thin, fragile shell with a slightly oval outline. It reaches almost 2 cm in length and is white in colour, sometimes with ferruginous (rusty) markings. Growth lines are visible on the outer surface of the shell and fine ridges. There may be some irregular grooves and dents. Small cardinal tooth in right valve, and recess in left valve into which this fits.

Habitat: Mud and muddy sand,

Distribution: Found around most coasts of Britain and Ireland.

Similar Species: There are other species of Thyasira that this could potentially be confused with.

Key Identification Features:

• Thin and fragile shell.
• Growth lines visible along with fine ridges.
• White, occasionally with rusty markings.
• Right valve with small cardinal tooth, left valve with recess for this tooth.

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

iNaturalist: Thyasira flexuosa at iNaturalist World Species Observations database.

GBIF data for Thyasira flexuosa

WoRMS: Thyasira flexuosa at World Register of Marine Species. Accepted name: Thyasira flexuosa (Montagu, 1803). AphiaID: 141662.

Classification: Biota; Animalia; Mollusca; Bivalvia; Autobranchia; Heteroconchia; Euheterodonta; Imparidentia; Lucinida; Thyasiroidea; Thyasiridae; Thyasira