''Argyropelecus'' is an

ocean The ocean (also the sea or the world ocean) is the body of salt water that covers approximately 70.8% of the surface of Earth and contains 97% of Earth's water. An ocean can also refer to any of the large bodies of water into which the wo ...

ray-finned fish Actinopterygii (; ), members of which are known as ray-finned fishes, is a class of bony fish. They comprise over 50% of living vertebrate species. The ray-finned fishes are so called because their fins are webs of skin supported by bony or h ...

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial n ...

in the

deep sea hatchetfish Marine hatchetfishes or deep-sea hatchetfishes are small deep-sea mesopelagic ray-finned fish of the stomiiform subfamily Sternoptychinae. They should not be confused with the freshwater hatchetfishes, which are not particularly closely related ...

family Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Idea ...

Sternoptychidae The marine hatchetfishes or deep-sea hatchetfishes as well as the related bottlelights, pearlsides and constellationfishes are small deep-sea ray-finned fish of the stomiiform family Sternoptychidae. They are not closely related to and should ...

. A collective name is " silver hatchetfishes", but this can also refer to a

species In biology, a species is the basic unit of Taxonomy (biology), classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of ...

of the

freshwater hatchetfish The freshwater hatchetfish are a family, Gasteropelecidae, of ray-finned fish from South and Central America. The common hatchetfish is the most popular member among fish keeping hobbyists. The family includes three genera: '' Carnegiella'' ...

es which are not particularly closely related to this. The large

pupil The pupil is a black hole located in the center of the iris of the eye that allows light to strike the retina.Cassin, B. and Solomon, S. (1990) ''Dictionary of Eye Terminology''. Gainesville, Florida: Triad Publishing Company. It appears black ...

s of these marine hatchetfishes enable them to see dim objects in the

deep sea The deep sea is broadly defined as the ocean depth where light begins to fade, at an approximate depth of 200 metres (656 feet) or the point of transition from continental shelves to continental slopes. Conditions within the deep sea are a combin ...

, where light barely penetrates.

Species

There are currently seven recognized extant species in this genus: * ''

Argyropelecus aculeatus ''Argyropelecus aculeatus'', the lovely hatchetfish or Atlantic silver hatchetfish, is a species of fish in the family Sternoptychidae. It may exceed standard length (SL). It lives in the mesopelagic zone of all oceans and performs diel vertical ...

Valenciennes Valenciennes (, also , , ; nl, label=also Dutch, Valencijn; pcd, Valincyinnes or ; la, Valentianae) is a commune in the Nord department, Hauts-de-France, France. It lies on the Scheldt () river. Although the city and region experienced a ...

, 1850 (lovely hatchetfish, Atlantic silver hatchetfish) * ''

Argyropelecus affinis ''Argyropelecus affinis'' is a species of ray-finned fish in the family Sternoptychidae, found in the tropical and subtropical Atlantic, Indian and Pacific Oceans. Common names for this fish include Pacific hatchetfish, deepsea hatchetfish and s ...

'' Garman, 1899 (Pacific hatchetfish) * ''

Argyropelecus gigas ''Argyropelecus gigas'', the giant hatchetfish or greater silver hatchetfish, is a marine fish of the genus ''Argyropelecus''. It is found in every ocean except the north Pacific in the mesopelagic zone of tropical and subtropical waters. "Gian ...

Norman Norman or Normans may refer to: Ethnic and cultural identity * The Normans, a people partly descended from Norse Vikings who settled in the territory of Normandy in France in the 10th and 11th centuries ** People or things connected with the Norm ...

, 1930 (giant hatchetfish, greater silver hatchetfish) * ''

Argyropelecus hemigymnus ''Argyropelecus hemigymnus'', the half-naked hatchetfish, short silver hatchetfish or spurred hatchetfish, is a deep-sea hatchetfish of the genus ''Argyropelecus'' found mesopelagically in the Atlantic, Indian, and Pacific Oceans as well as in ...

Cocco is a female Japanese pop / folk rock singer. Early life Cocco went to many ballet auditions, hoping to become a professional ballerina. She went to singing auditions to earn the traveling expenses for a ballet audition in Tokyo. She did not ...

, 1829 (half-naked hatchetfish, short silver hatchetfish, spurred hatchetfish) * ''

Argyropelecus lychnus ''Argyropelecus'' is an oceanic ray-finned fish genus in the deep sea hatchetfish family Sternoptychidae. A collective name is " silver hatchetfishes", but this can also refer to a species of the freshwater hatchetfishes which are not particul ...

'' Garman, 1899 (tropical hatchetfish) * ''

Argyropelecus olfersii ''Argyropelecus olfersii'' is a common species of marine hatchetfish, found in mesopelagic waters. Discovery and naming ''Argyropelecus olfersii'' was described by Georges Cuvier in Chapter 27 of '' Histoire Naturelle des Poissons'', based o ...

'' ( G. Cuvier, 1829) * ''

Argyropelecus sladeni ''Argyropelecus sladeni'', or Sladen's hatchetfish, is a species of ray-finned fish in the family Sternoptychidae, found in the tropical and subtropical Atlantic, Indian and Pacific Oceans. This small fish lives in the mesopelagic zone by day an ...

Regan The family name Regan, along with its cognates O'Regan, O Regan, Reagan, and O'Reagan, is an Anglicized form of the Irish surname Ó Riagáin or Ó Ríogáin, from Ua Riagáin. The meaning is likely to have originated in ancient Gaelic ''ri' ...

, 1908 (Sladen's hatchetfish, silvery hatchetfish) The earliest unequivocal fossils of ''Argyropelecus'' date from the start of the

Chattian The Chattian is, in the geologic timescale, the younger of two ages or upper of two stages of the Oligocene Epoch/ Series. It spans the time between . The Chattian is preceded by the Rupelian and is followed by the Aquitanian (the lowest sta ...

stage of the Late

Oligocene The Oligocene ( ) is a geologic epoch of the Paleogene Period and extends from about 33.9 million to 23 million years before the present ( to ). As with other older geologic periods, the rock beds that define the epoch are well identified but ...

Carnevale, Giorgio. "Redescription and phylogenetic relationships of Argyropelecus logearti (Teleostei: Stomiiformes: Sternoptychidae), with a brief review of fossil Argyropelecus." Rivista Italiana di Paleontologia e Stratigrafia (Research In Paleontology and Stratigraphy) 109.1 (2003). The original assessment of Eocene-aged otoliths from Austria assigned to this genus is now questioned.

References

External links

Information about Argyropelecus aculeatus
Sternoptychidae Extant Chattian first appearances Marine fish genera Ray-finned fish genera Taxa named by Anastasio Cocco {{Stomiiformes-stub