Shell very small, reaching only to 1.5 mm; shape discoidal. Sculpture of three strong keels with moderately deep interspaces between them, with the abapical (away from the apex) one most prominent. Umbilicus large, base with a strong additional keel that forms the “lower” angle of the aperture. A series of well-spaced radial ribs is present between this keel and the shell periphery. Color vitreous-white. Species identified by Harry G. Lee, Main photos by James F. Kelly.