Shell is round to trigonal in shape, and it has a prominent umbo (beak). Sculpture consists of coarse radial ribs (often with beads). The dentition (interior of shell) includes very fine teeth oriented along a narrow, but straight, hinge line.
Size: 20-30 mm.
Ecology: inhabits shallow marine waters (5-50 m), burrowing in sand near the sediment surface.
Geological range: Late Miocene (11-10 million years ago).
Geographic distribution: Caribbean – Panama; Pacific – Panama.