Description: A brittle shell with a flattened oval outline. Reaches up to around 2 cm in length. Colour can be white, pink, orange or yellow and either uniform or a mix of various shade of each, usually in concentric bands of colour. Occasionally each valve may be differently coloured but this is rare. Growth stages are visible and there are concentric lines on the outer surface of the shell. Both valves have 2 cardinal teeth, posterior is bifid in right, anterior in left. Right valve with 2 lateral teeth, left valve only 1. Inside of shell is a paler shade of the outside.

Habitat: Fine sand, from the lower shore to around 6 m.

Distribution: Found all around Britain and Ireland.

Similar Species: Could be confused with other tellins, careful inspection of cardinal and lateral teeth, as well as overall appearance should help to distinguish.

Key Identification Features:

• Flattened oval outline.
• Colour is variable but usually grouped into concentric bands of stronger shades.
• 2 cardinal teeth on each valve, 1 of which is bifid in each.
• Left valve with only 1 lateral tooth.
• Right valve with 1 lateral teeth.

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

iNaturalist: Macomangulus tenuis at iNaturalist World Species Observations database.

GBIF data for Macomangulus tenuis

WoRMS: Macomangulus tenuis at World Register of Marine Species. Accepted name: Macomangulus tenuis (da Costa, 1778). AphiaID: 878470.

Classification: Biota; Animalia; Mollusca; Bivalvia; Autobranchia; Heteroconchia; Euheterodonta; Imparidentia; Cardiida; Tellinoidea; Tellinidae; Tellininae; Macomangulus