Phylum Mollusca Linnaeus, 1758 - molluscs
   Class Polyplacophora Blainville, 1816 [monotypic] - chitons
     Subclass Polyplacophora Gray, 1821 [monotypic] see Class Polyplacophora Blainville, 1816
       Order Lepidopleurida Thiele, 1910
         Suborder Chitonina Thiele, 1909
           Family Chitonidae Rafinesque, 1815
             Subfamily Chitoninae Rafinesque, 1815 [monotypic]
               Genus Chiton Linnaeus, 1758
                 Subgenus Radsia Gray, 1847 see Genus Radsia Gray, 1847