Shell small, thin, trigonal, almost equivalve; rostrum abruptly truncated. Anterior and posterior dorsal slopes fairly straight, sharply and uniformly descending. Ventral margin convex, barely incurved below the truncated rostrum. Anterior end rather narrowly rounded low down on the same level as the rostrum. No clearly defined angle separating the rostrum from the rest of the shell. Surface smooth except for very faint irregular concentric growth lines. Hinge of left valve edentulous, that of right valve with an anterior and a posterior lateral, the latter being lamellate triangular as in the preceding species. Resilium large triangular, set slightly posterior to the beak. Length 3,5 mm.; height 2,5 mm.; thickness (one valve) 0,7 mm. (Holotype).

This species closely resembles the genotype, from which it differs mostly in shape, being proportionately much shorter.

New Zealand. Habitat: 60 fathoms off the Poor Knights Islands.