Argyropelecus


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 particularly closely related to this. The large pupils of these marine hatchetfishes enable them to see dim objects in the deep sea, where light barely penetrates.

Species

There are currently seven recognized extant species in this genus:Argyropelecus aculeatus Valenciennes, 1850 Argyropelecus affinis Garman, 1899 Argyropelecus gigas Norman, 1930 Argyropelecus hemigymnus Cocco, 1829 Argyropelecus lychnus Garman, 1899 Argyropelecus olfersii Argyropelecus sladeni Charles [Tate Regan|Regan], 1908

Fossil record

Extinct Argyropelecus species include:
File:Argyropelecus prisca 34maf olig romania.jpg|left|thumb|A. prisca, a fossil species from the Oligocene of Romania
The earliest unequivocal fossils of Argyropelecus date to the Bartonian stage of the Eocene. Previous to their discovery, the Eocene fossil record was restricted to otoliths from Austria, although their assignment to this genus is now questioned.