Shell small, thin, pink in colour, patelliform, elliptical, depressed; apex placed at about two-fifths of the total length from the anterior end; anterior and posterior ends are regularly rounded; anterior slope nearly straight but the posterior slightly convex; sculpture consisting of the rather irregular concentric growth lines and very weak radial threads, Length 5.6mm., breadth 4.8mm., height 1.4mm.

Both Ps. rugosoplicata Schepman and Ps. granulata Schepman are white species. Moreover the former has more elevated than this new species and the latter is differentiated from this new species by the different sculpture on its surface.

Type locality: Tosa Bay, Shikoku. Japan.