All at same scale, largest 10 mm high.
Shells 2 to 10 occupied by live animals; shells brown. Shell 1 vacant and in store for 70 years; shell yellow-brown. Beachworn shells, bleached and/or with worn away periostracum may be dull whitish. Usual adult height 3.5 mm to 7.5 mm, exceptionally 10 mm.
All have more than two protrusions in the aperture.
1: Caker Point, Cloghan, S. Kerry, Ireland. Leg. A.W. Stelfox 4th June 1948. 10mm high; unusually large for the species.
2 & 6: Menai Strait, Wales. Under embedded stones with L. bidentata at EHWS, sheltered, full salinity.
All others from by tidal River Dee under stones or driftwood at EHWS, low salinity, on Puccinellia maritima sward close to sandstone cliff; no L. bidentata found.
5: abapertural view of live specimen in water (more translucent than when dry). Lines indicate palatal protrusions visible through shell from exterior; double row of 4 near rim and single row of 4 far back in the aperture marking a previous lip position.

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