Vertigo (Vertigo) ronnebyensis (WESTERLUND, 1871)

Shell: Dextrous, whorls 4.5-5.1, most often 4.7-4.8. Shape ovate-cylindrical, from rather short to elongate, spire blunt. Whorls flat to moderately convex, suture shallow to moderately deep. Aperture nearly semicircular, palatal margin somewhat flattened. Teeth 0-4: columellar, of variable size; parietal, low and short lamellate or knob-shaped; upper and lower palatal, low and short lamellate or knob-shaped. Umbilicus deep, open and extremely narrow, or closed. Surface sculpture of distinct, regular striae, makes fresh shells silky. Colour light: from horny-yellowish to pale goldish-brown, teeth white.
Dimensions: Height 2.00-2.35 mm, breadth 1.15-1.33 mm, aperture height 0.45-0.58 mm, aperture breadth 0.68-0.83 mm, body whorl height 1.10-1.30 mm.
Ecology: A woodland species; deciduous, mixed and coniferous forests; in Northern Europe a typical inhabitant of coniferous, but also frequent in mixed forests; found in comparatively dry places, even on poor, non-calcareous soil.
Distribution: A North-European, continental species: great part of Scandinavia (except for the most mountaineous areas), becoming scarced in south-western Sweden and towards the coast in Norway; Finland; isolated localities scattered over north-western part of the Russia, neighbourhood of Berlin, recorded also from Rugen. In Poland recorded from the Pomeranian and Mazurian Lake Districts, Wielkopolska and Kujawska Lowlands, and vicinity of Warsaw.