The shell is roundly triangular in shape strong and heavy, with radiating ridges and varies in colour from greyish white through yellow to buff brown. The shell also has distinctive black and white markings. The interior surface of the shell is smooth with a deep purple band. It can grow up to 6 cm in length. The tip of the siphon is split. The body tissue of live specimens, especially the foot, are orange.Manila clams are indigenous to Japan and are widely used in commercial fisheries. It can tolerate water temperatures ranging from 0 to 23 °C. The Manila clam is superficially similar in shape and size to the paloured clam Tapes decussatus, however the flesh of live Manila clams, especially the foot is orange whilst in the paloured clam, the foot is white. The shell of the Manila clam also has distinctive black and white markings. When observed feeding underwater, the siphon of the Manila clam is joined but separate in the paloured clam.