Callochiton septemvalvis. North Devon. March 2016. © R. Durrant.
Dorsal surface of valves usually some shade of red, sometimes yellow or green, with or without irregular blotches or marbling. Head and tail valves, i and viii, are often darker than the other valves.
Girdle colour is usually similar to the adjacent valve colour, often with a transverse cream band by sutures i/ii and vii/viii and occasionally by other sutures, as on this one.

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