The Ipnopidae (deepsea tripod fishes) are a family of fishes in the order

Aulopiformes Aulopiformes is a diverse order (biology), order of Marine (ocean), marine ray-finned fish consisting of some 15 Extant taxon, extant and several prehistoric family (biology), families with about 45 genera and over 230 species. The common names ...

. They are small, slender fishes, with maximum length ranging from about . They are found in temperate and tropical deep waters of the

Atlantic The Atlantic Ocean is the second largest of the world's five oceanic divisions, with an area of about . It covers approximately 17% of Earth's surface and about 24% of its water surface area. During the Age of Discovery, it was known for se ...

, Indian, and

Pacific Ocean The Pacific Ocean is the largest and deepest of Earth's five Borders of the oceans, oceanic divisions. It extends from the Arctic Ocean in the north to the Southern Ocean, or, depending on the definition, to Antarctica in the south, and is ...

s. Abiotic factors, such as depth, temperature, dissolved oxygen concentration, pressure, and carbon concentration can all impact their distribution. Bathypterois dubius1

A number of species, especially in the genus ''

Bathypterois ''Bathypterois'' is a genus of deepsea tripod fishes. They are a diverse genus that belong to the greater family Ipnopidae and order Aulopiformes. They are distinguished by having two elongated pelvic fins and an elongated caudal fin, which all ...

'', have elongated

pectoral Pectoral may refer to: * The chest region and anything relating to it. * Pectoral cross, a cross worn on the chest * a decorative, usually jeweled version of a gorget * Pectoral (Ancient Egypt), a type of jewelry worn in ancient Egypt * Pectora ...

and

pelvic fin Pelvic fins or ventral fins are paired fins located on the ventral (belly) surface of fish, and are the lower of the only two sets of paired fins (the other being the laterally positioned pectoral fins). The pelvic fins are homologous to the hi ...

s. In the case of the tripodfish, ''

Bathypterois grallator The tripod fish or tripod spiderfish, ''Bathypterois grallator'', is a deep-sea benthic fish in the family Ipnopidae found at lower latitudes. It is now an iconic deep-sea fish, being observed and photographed by submersibles, using elongate ...

'', these fins are three times as long as the body — up to a meter in length — and are used for standing on the sea floor. Ipnopids either have tiny eyes, or very large eyes that lack any

lens A lens is a transmissive optical device that focuses or disperses a light beam by means of refraction. A simple lens consists of a single piece of transparent material, while a compound lens consists of several simple lenses (''elements'') ...

; in either case they have very poor vision and are unable to form an image. Ipnopidae is a species of fish that have adapted to living in the deep. Their skeleton is flatter with reinforced bony heads on its fin rays and its pelvic fins are located through the tips of the pectoral fin rays."Tripod Fish." Nature (London), vol. 240, no. 5379, 1972, pp. 284–284.

References

* Taxa named by Theodore Gill Aulopiformes families {{Aulopiformes-stub