Described by Verco as Myadora corrugata:
Shell transversely ovate, thin, subequilateral, inequivalve. Umbos apposed, acute, retroflexed. Anterior dorsal margin uniformly slightly convex. Posterior dorsal margin uniformly slightly concave; the two forming an angle of about 130°. Ventral margin slightly convex, anteriorly rising rapidly to form a well-rounded curve with the front dorsal margin; posteriorly forming a marked angle, slightly more than a right angle, with the truncated posterior extremity; in large specimens the ventral margin is slightly concave in front of this angle. Posterior extremity almost vertically straightly truncated, the end sloping slightly downwards and forwards, making a right angle with the post dorsal margin. Right valve convex, wellmarked ridge from umbo to postero-inferior angle; sculptured with very distinct, regular, concentric ribs, about one-half the width of the interspaces, and as high as wide, smooth and rounded, continuous from one dorsal margin to the other. Left valve a little smaller than the right, almost flat, very slightly rounded transversely, an indistinct ridge from umbo to postero-inferior angle, behind which the surface is quite flat; sculpture like that of the right valve, but not quite so deep, especially behind the umbonal ridge. There is a long narrow postumbonal area on the dorsal hingeline, smooth, slightly excavated, the right valve composing rather the larger part. Ventral margin very thin and simple. Internally, valves shining, pearly, indistinctly marked by the corrugations of the outside, furrows within corresponding with ridges without. A small triangular cartilage-pit within each apex ; there is a small umbonal ossicle. The right valve has a long linear furrow, with a scarcely projecting long lamina at its inner margin, for the reception of a long lamina on the left valve along the whole of the post-dorsal margin. The edge of the anterior-dorsal margin of the right valve scarcely projects, so as to enclose the left valve, and allow it to rest on the ledge within.
Length, anteroposterior, 14,25 mm.; umbo-ventral, 9 mm.; sectional diameter of apposed valves, 3,5 mm.

Southern Australia. Yankalilla Bay, Backstairs Passage, and Spencer Gulf.