With more than 17,000 known species (including tuna, seahorses, gobies, cichlids, flatfish, wrasse, perches, anglerfish, and pufferfish) known from both marine and freshwater ecosystems, it is the most speciose clade of extant vertebrates.

Elopomorpha (Elopiformes, Albuliformes, Notacanthiformes, Anguilliformes) Osteoglossomorpha (Hiodontiformes, Osteoglossiformes) Clupei (Clupeiformes) Alepocephali (Alepocephaliformes) Ostariophysi (Gonorynchiformes, Cypriniformes, Characiformes, Gymnotiformes, Siluriformes) Lepidogalaxiiformes (salamanderfish) Protacanthopterygii (Argentiniformes, Galaxiiformes, Esociformes, Salmoniformes) Stomiati (Stomiiformes, Osmeriformes) Ateleopodidae (jellynoses) Aulopiformes (lizardfish) Myctophiformes (lanternfish) Lampripterygii (Lampriformes) Paracanthopterygii (Percopsiformes, Zeiformes, Stylephoriformes, Gadiformes) Polymixiiformes (beardfish) Beryciformes (alfonsinos, whalefishes) Trachichthyiformes (pinecone fishes, slimeheads) Holocentriformes (squirrelfish, soldier fishes) Percomorpha

Gobiiformes (gobies) Kurtiformes (nurseryfishes, cardinalfishes) Anabantiformes (snakeheads, Siamese fighting fish, gouramies) Synbranchiformes Polynemidae (threadfins) Lactariidae (false trevally) Menidae (moonfish) Nematistiidae (roosterfish) Echeneidae (remoras) Coryphaenidae (dolphinfish) Rachycentridae (cobia) Sphyraenidae (barracudas) Centropomidae (snooks) Pleuronectiformes (flatfish) Carangidae (jacks) Istiophoriformes (billfish) Leptobramidae (beachsalmons) Toxotidae (archerfish) Cichliformes (cichlids, convict blennies) Polycentridae (leaffish) Beloniformes (needlefish, flying fish, halfbeaks) Atheriniformes (silversides, rainbowfish, etc.)

Cyprinodontiformes (tooth-carps) Ambassidae (Asiatic glassfishes) Congrogadidae (eel blenny) Pomacentridae (damselfishes, clownfish) Embiotocidae (surfperches) Mugiliformes (mullets) Lipogramma Plesiopidae (roundheads) Pseudochromidae (dottybacks) Grammatidae (basslets) Opistognathidae (jawfishes) Blenniiformes (blennies, clinids, sand stargazers) Gobiesociformes (clingfishes) Gerreiformes (mojarras) Uranoscopiformes (stargazers) Centrogenyidae (false scorpionfish) Labriformes (wrasses, cales, parrotfish) Perciformes (perches, sticklebacks, scorpionfishes, etc.)

Moronidae (temperate basses) Sillaginidae (smelt-whitings) Ephippiformes (spadefishes, batfishes) Chaetodontiformes (butterflyfishes) Sciaenidae (drums, croakers) Acanthuriformes (surgeonfishes, ponyfishes) Monodactylidae (moonyfishes, fingerfishes) Emmelichthyidae (rovers) Pomacanthidae (angelfishes) Lutjaniformes (snappers) Callanthiidae (splendid perches) Malacanthidae (tilefishes) Lobotiformes (tripletails) Spariformes Siganidae (rabbitfishes) Priacanthiformes (bigeyes, bandfishes) Scatophagidae (scats) Caproiformes (boarfishes) Lophiiformes (anglerfishes) Tetraodontiformes (pufferfishes, triggerfishes, etc.)