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 Mopaliidae Dall, 1889
            
 Subfamily Mopaliinae Dall, 1889
              
 Genus Plaxiphora Gray, 1847
                
 1 Subgenus Plaxiphora Gray, 1847
                
 2 Subgenus Fremblya H. Adams, 1866
                
 3 Subgenus Mercatora Leloup, 1942