Peters
Diagnosis: Shell stout, thick-walled, nearly triangular in lateral view. Dorsal wall broadly rounded, convex; ventral wall narrow, slightly convex. Aboral wall flattened to slightly concave. Ventral corner may expand into rounded projection. Peristome process long and twisted, originating from one side of dorsal mid-line, and extending into 2 asymmetrical, flange-like teeth.
Length (including process): 0.15-0.18 mm.