Phylum [Mollusca] Linnaeus, 1758 - molluscs
   Class Bivalvia Linnaeus, 1758 - bivalves
     Order Mytiloida Férussac, 1822 see Order Mytilida Férussac, 1822
       Superfamily Pectinacea Rafinesque, 1815, nom. illeg. see Superfamily Pectinoidea Rafinesque, 1815
         Family Spondylidae Gray, 1826 - thorny oysters
           Genus Spondylus Linnaeus, 1758
             Subgenus Spondylus (Eltopera) Iredale, 1939