Shell of the Week: The Spiny Piddock
Jouannetia quillingi Turner, 1955 is a member of the family Pholadidae, a group that also includes the Angel Wing (Cyrtopleura costata), and piddock species of the genus Martesia.
The shell measures up to 18 mm (3/4 inch), and the left and right valves differ from each other in this species, with concentric ribs stronger on the right valve. This species is rare in shallow water, preferring to bore into rocky or coral-related offshore bottoms. The presence of special mantle glands in this species suggests that it may employ chemical dissolution to help the boring action carried out by the anterior part of the shell valves.