Polyipnus

Polyipnus Temporal range: Early Oligocene to Present
Threelight hatchetfish (Polyipnus triphanos)
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Subphylum:	Vertebrata
Class:	Actinopterygii
Subclass:	Neopterygii
Order:	Stomiiformes
Family:	Sternoptychidae
Subfamily:	Sternoptychinae
Genus:	Polyipnus Günther, 1887
Diversity
32 species

Polyipnus is an oceanic ray-finned fish genus which belongs in the family Sternoptychidae. This is the largest genus of the marine hatchetfishes (Sternoptychinae) and indeed of the entire Sternoptychidae. It is not quite as apomorphic as their relatives; it may be that the genus is actually a paraphyletic assemblage of less advanced Sternoptychinae and would need to be split.

Species

There are currently 32 recognized species in this genus:^[1]

Polyipnus aquavitus R. C. Baird, 1971 (Aquavit hatchetfish) Polyipnus asper Harold, 1994 Polyipnus asteroides L. P. Schultz, 1938 Polyipnus bruuni Harold, 1994 Polyipnus clarus Harold, 1994 (Slope hatchetfish) Polyipnus danae Harold, 1990 Polyipnus elongatus Borodulina, 1979 Polyipnus fraseri Fowler, 1934 Polyipnus indicus L. P. Schultz, 1961 Polyipnus inermis Borodulina, 1981 Polyipnus kiwiensis R. C. Baird, 1971 (Kiwi hatchetfish) Polyipnus laternatus Garman, 1899 Polyipnus latirastrus Last & Harold, 1994 (Combside hatchetfish) Polyipnus limatulus Harold & Wessel, 1998 Polyipnus matsubarai L. P. Schultz, 1961 Polyipnus meteori Kotthaus, 1967

Polyipnus nuttingi C. H. Gilbert, 1905 (Nutting's hatchetfish) Polyipnus oluolus R. C. Baird, 1971 Polyipnus omphus R. C. Baird, 1971 Polyipnus ovatus Harold, 1994 Polyipnus parini Borodulina, 1979 Polyipnus paxtoni Harold, 1989 (Paxton's hatchetfish) Polyipnus polli L. P. Schultz, 1961 Polyipnus ruggeri R. C. Baird, 1971 (Rugby hatchetfish) Polyipnus soelae Harold, 1994 (Soela hatchetfish) Polyipnus spinifer Borodulina, 1979 Polyipnus spinosus Günther, 1887 (Spiny hatchetfish) Polyipnus stereope D. S. Jordan & Starks, 1904 Polyipnus surugaensis Aizawa, 1990 Polyipnus tridentifer McCulloch, 1914 (Three-spined hatchetfish) Polyipnus triphanos L. P. Schultz, 1938 (Threelight hatchetfish) Polyipnus unispinus L. P. Schultz, 1938

Fossils of this genus show that they have existed at least since the Early Oligocene, about 30 million years ago.^[2]

References

1. Froese, Rainer, and Daniel Pauly, eds. (2012). Species of Polyipnus in FishBase. February 2012 version.
2. Sepkoski, Jack (2002): [Polyipnus]. In: A compendium of fossil marine animal genera. Bulletin of American Paleontology 364: 560. HTML database excerpt