Spondylus regiusSpondylus regius, the regal thorny oyster, is a species of bivalve mollusc in the family Spondylidae. It can be found in the Western Pacific, and can grow 156 mm in length.Distribution and habitatSpondylus regius is found in the Red Sea, Philippines, Japan, and Coral Sea waters on coral debris from depths of 5 to 80 meters.