Koi (Cyprinus carpio) are classified in the taxonomic hierarchy as follows:

• Kingdom - Animalia
  • Phylum - Chordata
    • SubPhylum - Vertebrata
      • Superclass - Osteichthyes
        • Class - Actinopterygii (Ray finned fishes)
          • Subclass - Neopterygii
            • Infraclass - Teleostei (Bony Fishes)
              • Superorder - Ostariophysi (Carp, minnows, Catfish, etc - have Weberian Apparatus)
                • Order - Cypriniformes (Carp, Minnows, etc.)
                  • Family - Cyprinidae
                    • Genus - Cyprinus
                      • Species- Cyprinus carpio
                        • Subspecies - (koi)*

Note: Cyprinus spp. refers to all species in the "Cyprinus" Genus