Spire conical with distinctly convex sides. Apex (slightly) oblique. Whorls 4 3/8-4 7/8; top whorls convex; last whorl obtusely angular at the periphery, slightly convex above and below. Constriction with a short and inconspicuous parietalis, a transverse palatalis, an inconspicuous columellaris. Tuba bulging and then abruptly narrowed towards the constriction, slightly angular below. Radial ribs widely spaced (1-2 ribs/0.5 mm on the penultimate whorl and half-way on the tuba), those on the spire hardly visible but on the lower half of the whorls with a deeply trough-shaped to almost tubular, slightly curved projection, abrading to a scar with a single deep loop; those on the tuba similar but more distinct, with a longer, strongly curved projection below which is swollen at the tip. Spiral striation absent. Umbilicus open, 0.35-0.50 mm across. Aperture tilted up to 20° with regard to the coiling axis, its upper margin widely above the level of the apex, elliptic. Peristome distant from the spire, double; outer peristome hardly to moderately spreading beyond the inner all around, or sometimes gradually narrowed towards, and absent along the side of the aperture which is closest to the spire; inner peristome not or hardly protruding from the outer, spreading. Spire: height 1.9-2.2 mm; width 1.7-2.0 mm; index 1.0-1.1. Total width 2.8-3.1 mm. Height aperture 1.4 mm; width 1.1 mm.