Cantharidus

Cantharidus, common name the kelp shells, is a genus of sea snails, marine gastropod molluscs of the family Trochidae, the top shells.

==Description== The shell has an ovate-conic or pyramidal shape. It is imperforate, smooth or spirally sculptured outside, brilliantly iridescent within. The colors are generally bright and variegated. The aperture is less than half the length of shell, longer than wide, ovate. The columella is usually more or less folded or toothed near the base.