Columella columella (MARTENS, 1830)

Shell: Dextrous. Shape cylindrical. Up to 7.5 whorls. Whorls moderately to strongly convex, suture deep. Aperture outline distinctly oval. Umbilicus deep, open. Surface sculpture of rather strong distinct and irregular striae. Colour light to dark brown, sometimes with a reddish tint.
Dimensions: Maximum height: 2.65-4.00 mm, maximum breadth: 1.25-1.50 mm.
Ecology: A calciphile: marshy grassland, wet subarctic woodland, grey willow thickets, alpine meadows. In Poland limited to epilithic grassland in the calcareous part of the Tatra Mts., from 1500 m a.s.l. upwards; found in tufts of Saxifraga aizoon, S. aizoides, Dryas octopetala, among Salix herbacea and S. reticulata, most often accompanied by V. arctica and V. alpestris.
Distribution: An Arctic-Alpine species: mountains of Scandinavia mainly beyond the Arctic Circle, a part of Asia between 61° and 69°N, isolated localities in the Alps and Tatra Mts. and Crimea. In Poland only the calcareous part of the Tatra Mts.