The beautiful Royal Spiny Oyster (Spondylus Regis) is closely related to the scallop and live permanently attached to corals and rocks. Sometimes known as ‘Chrysanthemum Shells’ due to their flower-like appearance. Royal Thorny Oyster Shell 4" to end of spines True Collectors Shell Thorny oysters, Family Spondylidae Although resembling oysters, the Thorny Oysters or Chrysanthemum shells are more closely related to the scallops. The “ball and socket” hinge is characteristic. Marine growths on the long spines offer camouflage. Great variation in shape, colors and spines makes identification of the two dozen or more species difficult.
Size is measured from tip of spine to base or hinge. These are also hinged so they open and close