Coral-eating Mussel

Shell size to 20 mm; Shell inflated, with ridge on postero-dorsal part of shell bearing radiating lines. Shell margins finely serrated. Interior of shell iridescent, bluish-white. Periostracum thick, heavy, but often absent in dead shells. This is a coral-rock boring species, found locally within small coral heads. The common name is a misnomer, as these mussels do not eat coral, only use the coral skeleton as substrate for boring.