Phylum Chordata Bateson, 1885 - chordates
   Subphylum Vertebrata Cuvier, 1812 - vertebrates
     Pisces
       Class Actinopterygii Woodward, 1891 - ray-finned fishes
         Order Synbranchiformes - swamp eels
           Family Chaudhuriidae
           Family Mastacembelidae - spiny-eels
           Family Synbranchidae - swamp-eels