Juvenile.

1: very small snout with opening to pouch containing proboscis used for feeding.

2: bilaminate anterior of foot.

3: median groove in foot containing posterior pedal gland.

4: mantle on interior of shell.

5: mantle cavity containing ctenidium and osphradium.

6: exhalent siphon formed by fold of mantle resting in posterior siphonal canal of shell.

7: mantle on exterior of shell.

Shell length 9.3 mm. Anglesey, Wales. September 2015. Leg. J. Light.