Description: A solid bivalve with a broadly oval outline that reaches up to 6.5 cm in size, although is more commonly smaller. Colour is cream, light yellow or light pink-brown, with varying red-brown patterns including zigzags, streaks and blotches. It can however be completely uniform in colour, with no patterning. The periostracum is thin and smooth. On the exterior of the shell there is a sculpture of fine concentric ridges and grooves. There are 3 cardinal teeth and no lateral teeth in each valve. In the right valve the the posterior cardinal tooth is bifid, in the left the central one is bifid. Interior of the shell is a glossy white, sometimes within umbones or pallial sinus it is stained pink or orange. Pallial sinus doesn't extend deeply.

Habitat: Gravel, shelly gravel, sandy gravel or muddy gravel as well as coarse sand. Found from low water down to over 180 m.

Distribution: Widespread around all coasts of Britain and Ireland.

Similar Species: Could be confused with Politapes aureus, or possibly Ruditapes decussatus and Ruditapes philippinarum.

Key Identification Features:

• Solid with broadly oval outline.
• Cream, yellow to light pink-brown with varying red-brown patterning.
• 3 cardinal teeth and no lateral teeth in each valve.
• Left valve has central bifid cardinal tooth.
• Right valve has posterior bifid cardinal tooth.
• Pallial sinus does not extend deeply.

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

iNaturalist: Polititapes rhomboides at iNaturalist World Species Observations database.

GBIF data for Polititapes rhomboides

WoRMS: Polititapes rhomboides at World Register of Marine Species. Accepted name: Polititapes rhomboides (Pennant, 1777). AphiaID: 745846.

Classification: Biota; Animalia; Mollusca; Bivalvia; Autobranchia; Heteroconchia; Euheterodonta; Imparidentia; Venerida; Veneroidea; Veneridae; Tapetinae; Polititapes