Vertigo (Vertigo) moulinsiana (DUPUY, 1849)

Shell: Dextrous, whorls 4.5-5.2, most often 4.7-4.8. Shape ovate, from short to elongate, spire tapered. Whorls flat to moderately convex, suture shallow to moderately deep. Aperture elongatedly heart-shaped. Teeth 4-8. Columellar, short fold-like or knob-shaped; parietal, short and high lamellate; upper and lower palatal; angular; suprapalatal (1, rarely 2); basal; infrapalatal; interpalatal. Umbilicus shallow, closed. Surface sculpture of very delicate, irregular, poorly visible striae. Colour from horny-yellow to brown.
Dimensions: Height 2.25-2.73 mm, breadth 1.33-1.65 mm, aperture height 0.65-0.83 mm, aperture breadth 0.88-1.08 mm, body whorl height 1.40-1.63 mm.
Ecology: A typical inhabitant of marshes and fens, most often beds of reed, sedge of Glyceria on lake shores and river banks; climbing leaves and stems of various species of Typha, Iris, Glyceria, Carex, Phragmites where it stays 30-50 cm above the ground or water surface, only in late fall descending to the ground to spend winter there; in autumn and early spring staying among plant debris; never found in habitats of apparently suitable character but regularly mowed or grazed.
Distribution: An Atlantic-Mediterranean species, with localities scattered over the southern part of the British Isles, Denmark, southernmost Sweden and Lithuania. Its southern distribution border is not known precisely. In Poland, like in the remaining parts of its range, it is very local and the number of its localities still decreases as a result of destruction (mainly drainage) of its habitats; recorded from Mazurian and Lubuskie Lake Districts, vicinity of Warsaw and Bialowieza Forest.