By Vermeulen (1994)
"Spire conical with flat to slightly concave sides. Apex not oblique. Whorls 4 1/2- 5 1/4, convex; last whorl slightly angular at the periphery, slightly convex above and below. Constriction with a very distinct, lamella-shaped parietalis which continues upe to, or over half-way the tuba. Tuba free from the spire, gradually narrowed towards the constriction, rounded below. Radial ribs rather closely placed to widely spaced (3-8 ribs/0.5 mm on the penultimate whorl, as well as half-way the tuba), those on the spire (slightly) sinuous, low; those on the tuba not or hardly sinuous below, much higher that those on the spire. Spiral striation absent. Umbilicus open, 0.10-0.20 mm across. Aperture hardly tilted with regard to the coiling axis, its upper margin widely below the level of the apex, circular or slightly angular. Peristome double, outer peristome distinctly spreading beyond the inner, but gradually narrowed towards, and absent along the right side of the aperture, its margins often slightly bent backwards; inner peristome distinctly protruding from the outer, somewhat spreading, its outer surface and the upper surface of the outer peristome with numerous fine lamellae. Spire: height 1.5-1.9 mm; width 1.0-1.2 mm; index 1.4-1.6. Total width 2.2-2.4 mm. Height and width aperture 0.5-0.6 mm"