Disarticulated valves; inset tail (viii) and head (i) valves enlarged. Sublittoral, Orkney. February 2015. Leg. P. Lightfoot per J. Porter.
The head valve (i) is almost semicircular with, when in live position, a shallow V posterior edge. The tail valve (viii) is small and about twice as wide as its antero-posterior length. The unobtrusive, antemedian mucro (1) is encircled by the concentric growth lines . The colour of the antemucronal area (2) resembles that of the jugal area of intermediate valves (3).

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