Vertigo (Vertilla) angustior JEFFREYS, 1830

Shell: Sinistrous, whorls 4.5-5.1, most often 5.0. Shell spindle-shaped, short to elongate, spire tapered, body whorl strongly narrowed at its base. Whorls moderately convex, suture moderately deep. Aperture heart-shaped. Teeth 4: columellar, in front view like a relatively large lamella parallel to the aperture plane; parietal and angular, high lamellate; palatal. Umbilicus shallow, closed. Surface sculpture of very distinct, strong and regular striae. Shell almost opaque, from silky to mat. Colour from horny-yellowish to rather dark reddish-brown, teeth and callus ligther.
Dimensions: Height 1.50-1.90 mm, breadth 0.90-1.00 mm, aperture height 0.40-0.53 mm, aperture breadth 0.45-0.63 mm, body whorl height 0.85-1.00 mm.
Ecology: A calciphile of habitat preferences varying with climate. In Central Europe closely associated with habitats of high and constant humidity; calcareous fens, marshes, margins of lakes, less often alder swamps.
Distribution: A European species: great part of Europe from Portugal to Caspian Sea, in the north to ca. 60°; not recorded from the southernmost fringes of Europe; in the east to Ural, recorded also from northern Iran. In Poland rather rare though its localities are scattered in all the studied regions.