"Shell small, up to ca. 14 mm high, fragile, oblique, elongate, inequivalve, inequilateral, semi-transparent white, right valve more convex than left, auricles unequal, umbonal angle ca. 90". Prodissoconch ca. 200 pm in height. Left valve externally sculptured over entire surface with regular spaced concentric lamellae that enlarge towards ventral margin. Lamellae near periphery more strongly curved and more irregularly and closely spaced. Delicate radial lirae between concentric lamellae, more prominent directly beneath each concentric lira. Anterior and posterior auricles with curved, closely spaced concentric lirae, somewhat more prominent and widely arranged on anterior. Anterior auricle larger than posterior auricle, sculpture similar to that of disc margins. External sculpture visible from interior. Interior surface nacreous. Right valve with regular concentric lamellae and many delicate interstitial radial lirae similar to those on left valve. Anterior auricle separated from disc by distinct suture, sculptured with irregularly spaced, concentric lamellae, developed into spinous scales on dorsal margin. Posterior auricle with close-set concentric lamellae and continuous with the disc margin. Resilifer triangular. No cardinal crura exposed. Only an inactive ctenolium is developed (two teeth of active ctenolium are developed in paratype from BIOCAL: stn CP 72). Byssal notch present." (fide Dijkstra, 1995)
Size: Normal adult size range is 10 to 15 mm.

From eastern New Caledonia to the New Hebrides.
Habitat: Deep water, on fine muddy bottoms.