Osteoglossomorpha is a group of bony fish in the Teleostei

Teleostei

Teleostei is one of three infraclasses in class Actinopterygii, the ray-finned fishes. This diverse group, which arose in the Triassic period, includes 20,000 extant species in about 40 orders; most living fishes are members of this group...

.

Notable members

A notable member is the Arapaima

Arapaima

The arapaima, pirarucu, or paiche is a South American tropical freshwater fish. It is a living fossil and one of the largest freshwater fishes in the world.-Anatomy and morphology:...

 (Arapaima gigas), the largest freshwater

Freshwater

Fresh water is naturally occurring water on the Earth's surface in ice sheets, ice caps, glaciers, bogs, ponds, lakes, rivers and streams, and underground as groundwater in aquifers and underground streams. Fresh water is generally characterized by having low concentrations of dissolved salts and...

 fish in South America

South America

South America is a continent situated in the Western Hemisphere, mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere. The continent is also considered a subcontinent of the Americas. It is bordered on the west by the Pacific Ocean and on the north and east...

 and one of the very largest bony fishes alive. Other notable members include the bizarre freshwater elephantfishes (Mormyridae).

Systematics

Most osteoglossomorph lineages are extinct today. Only the somewhat diverse "bone-tongues" (Osteoglossiformes

Osteoglossiformes

Osteoglossiformes is a relatively primitive order of ray-finned fish that contains two sub-orders, the Osteoglossoidei and the Notopteroidei. All of the living species inhabit freshwater...

) and two species

Species

In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...

 of mooneye

Mooneye

The mooneyes are a family, the Hiodontidae, of primitive ray-finned fish comprising two living and three extinct species in the genus Hiodon. They are large-eyed, fork-tailed fish that physically resemble shads. Their common name comes from the metallic gold or silver shine of their eyes.The higher...

s (Hiodontiformes) remain.