The valves are white, delicate, and diaphanous, rounded upon the anterior side, truncated obliquely upon the posterior sid.

The side is bounded outwardly by an obtuse angle, which extends from the beak to the lower and posterior edges.

The exterior surface presents some very prominent transverse folds, rounded, undulating, more or less numerous.

The anterior muscular impression is very superficial, elongated, and very narrow ; the posterior rounded and small.

[2] Cyathodonta plicata is found off the U.S. Virgin Islands, Saint Thomas.