The anterior side of the shell is short and rounded, with an excavation near the umbones, which are located near the front of the shell. The posterior side of the shell is elongated. The dorsal margin of the shell is straight, while the ventral margin is sharp and convex, sloping upward towards each end. The outside of the shell is ornamented with purple or pale brown concentric rays, with 4 or 5 broad white radial bands.