The adult shell is ovoid and is likened to a coffee bean in Dutch, French and Norwegian and to a kernel of oats in Scots.

Profile of right side (R) and left (L) when in living position.

1: approximate position of enveloped spire at posterior.

2 – 2: apertural face (ventral on live animal) is white.

3: dorsal and lateral faces have pinkish shell-material deposited in grooves.

4: no varix on columellar side of body-whorl; whorl bulges down centrally.

5: thickened white labial varix near palatal lip.

Adult, height (longest dimension) 10.8 mm. August 2010. Menai Strait, Wales.