Adults
Left: H. 10.1 mm, Orkney, March 1973. Distinct spire, 52% of shell height. Aperture 49% of height and about 30% of area of apertural view. Four bands (1, 2, 3, 4) on body whorl; bands 1 & 2 enter aperture leaving only 3 & 4 visible on other whorls.
Columellar groove (5). Parietal lip is a whitish glaze (6). Outer lip continues round to form abapertural edge of groove (7). White shell where thin periostracum worn off dead shell (8); rest of shell yellowed by periostracum. Fine spiral lines discernible on brown band (9).
Right: H. 9.4 mm, west Anglesey, March 2014. Spire 51% of shell height.