1: translucent horn-coloured operculum.
2: long, translucent pallial tentacle protruding beyond shell.
3: whitish posterior of opercular lobe.
4: opercular lobe darkly pigmented at anterior only.
5: mantle greyish-white with some yellow.
6: eye on small swelling at base of tentacle.
7: anterior of sole expanded; bilaminate edge has outlet within for mucus from anterior pedal gland; spreads mucus to lubricate creeping .
8: purple/black peripheral line on foot extends well beyond proximity of broad transverse band on dorsal surface of foot (indistinct on some specimens).
9: central pore of opaque posterior pedal gland; secretes thread of mucus that hardens on contact with sea water; used to anchor the snail and act as climbing line in its movement around algae.
10. translucent peripheral band of foot not occupied by opaque gland. Height 2.6 mm. Llŷn Peninsula, Wales. March 2015.