Osteichthyes, popularly referred to as the bony fish, is a diverse superclass of fish that have skeletons primarily composed of bone tissue. They can be contrasted with the Chondrichthyes, which have skeletons primarily composed of cartilage. The vast majority of fish are members of Osteichthyes, which is an extremely diverse and abundant group consisting of 45 orders, and over 435 families and 28,000 species. It is the largest class of vertebrates in existence today. The group Osteichthyes is divided into the ray-finned fish (Actinopterygii) and lobe-finned fish (Sarcopterygii). The oldest known fossils of bony fish are about 425 million years old, which are also transitional fossils, showing a tooth pattern that is in between the tooth rows of sharks and bony fishes.
The Amiiformes order of fish has only one extant species, the bowfin. These Amiiformes are found in the freshwater systems of North America, in the United States and parts of southern Canada. They live in freshwater streams, rivers, and swamps.
Semionotiformes is an order of primitive, ray-finned, primarily freshwater fish from the Middle Triassic (Anisian) to the Late Cretaceous (Maastrichtian). The best-known genus is Semionotus of Europe and North America. Their closest living relatives are gars (Lepisosteidae), with both groups belonging to the clade Ginglymodi within the Holostei.
Actinopteri is the sister group of Cladistia in the class Actinopterygii.
Neopterygii is a subclass of ray-finned fish (Actinopterygii). Neopterygii includes the Holostei and the Teleostei, of which the latter comprise the vast majority of extant fishes, and over half of all living vertebrate species. While living holosteans include only freshwater taxa, teleosts are diverse in both freshwater and marine environments. Many new species of teleosts are scientifically described each year.
The superorder Elopomorpha contains a variety of types of fishes that range from typical silvery-colored species, such as the tarpons and ladyfishes of the Elopiformes and the bonefishes of the Albuliformes, to the long and slender, smooth-bodied eels of the Anguilliformes. The one characteristic uniting this group of fishes is they all have leptocephalus larvae, which are unique to the Elopomorpha. No other fishes have this type of larvae.
Holostei is a group of ray-finned bony fish. It is divided into two major clades, the Halecomorphi, represented by a single living species, the bowfin, as well as the Ginglymodi, the sole living representatives being the gars (Lepisosteidae), represented by seven living species in two genera. The earliest members of the clade appeared during the Early Triassic, over 250 million years ago.
The Palaeonisciformes (Palaeoniscida) are an extinct order of early ray-finned fishes (Actinopterygii). Palaeonisciformes sensu lato first appeared in the fossil record in the Late Silurian and last appeared in the Late Cretaceous. The name is derived from the Ancient Greek words παλαιός and ὀνίσκος, probably pertaining to the organization of the fishes' scales, similar to the exoskeletal plating of woodlice.
Acanthomorpha is an extraordinarily diverse taxon of teleost fishes with spiny-rays. The clade contains about one third of the world's modern species of vertebrates: over 14,000 species.
Aspidorhynchiformes is an extinct order of ray-finned fish. It contains only a single family, the Aspidorhynchidae. Members of the group are noted for their elongated, conical rostrums, of varying length, formed from fused premaxillae. They are generally interpreted as stem-group teleosts. The range of the group extends from the Middle Jurassic to the late Paleocene.
Pachycormiformes is an extinct order of marine ray-finned fish known from the Early Jurassic to the end of the Cretaceous. It only includes a single family, Pachycormidae. They were characterized by having serrated pectoral fins, reduced pelvic fins and a bony rostrum. Their exact relations with other fish are unclear, but they are generally considered to be teleosteomorphs, more closely related to teleosts than to Holostei. Pachycormiformes are morphologically diverse, containing both tuna and swordfish-like carnivorous forms, as well as edentulous suspension-feeding forms, with the latter including the largest ray finned fish known to have existed, Leedsichthys, with an estimated maximum length of 16 metres.
Prohalecites is an extinct genus of ray-finned fish from the Ladinian and possibly Carnian (Triassic) of Italy. It is the oldest known teleosteomorph, a group that includes extant teleosts and their close fossil relatives.
Cladistia is a clade of bony fishes whose only living members are the bichirs. Their major synapomorphies are a heterocercal tail in which the dorsal fin has independent rays, and a posteriorly elongated parasphenoid.
Crossognathiformes is an extinct order of ray-finned fish that lived from the Late Jurassic to the Eocene. Its phylogenetic placement is disputed; some authors have recovered it as part of the teleost stem group, while others place it in a basal position within crown group Teleostei.
Halecomorphi is a taxon of ray-finned bony fish in the clade Neopterygii. The sole living Halecomorph is the bowfin, but the group contains many extinct species in several families in the order Amiiformes, as well as the extinct orders Ionoscopiformes, Panxianichthyiformes, and Parasemionotiformes. The fossil record of halecomorphs goes back at least to the Early Triassic epoch.
Percomorpha is a large clade of ray-finned fish that includes the tuna, seahorses, gobies, cichlids, flatfish, wrasse, perches, anglerfish, and pufferfish.
Otocephala is a clade of ray-finned fishes within the infraclass Teleostei that evolved some 230 million years ago. It is named for the presence of a hearing (otophysic) link from the swimbladder to the inner ear. Other names proposed for the group include Ostarioclupeomorpha and Otomorpha.
Amia, commonly called bowfin, is a genus of bony fish related to gars in the infraclass Holostei. They are regarded as taxonomic relicts, being the sole surviving species of the order Amiiformes, which dates from the Jurassic to the Eocene, persisting to the present. There is one living species in Amia, Amia calva, and a number of extinct species which have been described from the fossil record.
Parasemionotiformes is an extinct order of neopterygian ray-finned fish that existed globally during the Triassic period. It comprises the families Parasemionotidae and Promecosominidae. Many of the included genera are monotypic and most species lived during the Early Triassic epoch.
Scorpaenini is a tribe of marine ray-finned fishes, one of two tribes in the subfamily Scorpaeninae. This tribe contains the "typical" or "true" scorpionfishes. The taxonomy of the scorpionfishes is in some flux, the 5th Edition of Fishes of the World treats this taxa as a tribe within the subfamily Scorpaeninae of the family Scorpaenidae within the order Scorpaeniformes, while other authorities treat it as a subfamily within a reduced family Scorpaenidae within the suborder Scorpaenoidei, or the superfamily Scorpaenoidea within the order Perciformes.