''Gvozdarus'' is a

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...

of marine

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 hor ...

es belonging to the

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

Nototheniidae : ''In some scientific literature, the term "cod icefish" is used to identify members of this family. This should not be confused with the term "icefish," which refers to the "white-blooded" fishes of the family Channichthyidae. See Icefish (disam ...

, the notothens or cod icefishes. It is native to the

Southern Ocean The Southern Ocean, also known as the Antarctic Ocean, comprises the southernmost waters of the World Ocean, generally taken to be south of 60° S latitude and encircling Antarctica. With a size of , it is regarded as the second-small ...

Taxonomy

''Gvozdarus'' was first formally described as a genus in 1989 by the Soviet ichthyologist

Arkady Vladimirovich Balushkin Arkady (russian: Арка́дий, Arkadiy) is a Slavic masculine given name, ultimately derived from the Greek name Αρκάδιος, meaning “from Arcadia”. The Latin equivalent is Arcadius. Notable people with the name include: People: *Ark ...

with the type species by

monotypy In biology, a monotypic taxon is a taxonomic group (taxon) that contains only one immediately subordinate taxon. A monotypic species is one that does not include subspecies or smaller, infraspecific taxa. In the case of genera, the term "unispec ...

being ''Gvozdarus svetovidovi'', a second species has subsequently been described. Some authorities place this taxon in the

subfamily In biological classification, a subfamily (Latin: ', plural ') is an auxiliary (intermediate) taxonomic rank, next below family but more inclusive than genus. Standard nomenclature rules end subfamily botanical names with "-oideae", and zoologi ...

Pleuragrammatinae, but the 5th edition of ''

Fishes of the World ''Fishes of the World'' by the American ichthyologist Joseph S. Nelson (1937–2011) is a standard reference for fish systematics. Now in its fifth edition (2016), the work is a comprehensive overview of the diversity and classification of the ...

'' does not include subfamilies in the Nototheniidae. The name of the genus is a Latinised version of a local name for the

zander The zander (''Sander lucioperca''), sander or pikeperch, is a species of ray-finned fish from the family Percidae, which includes the perches, ruffes and darters. It is found in freshwater and brackish habitats in western Eurasia. It is a popul ...

(''Sander lucioperca'') in

Veliky Novgorod Veliky Novgorod ( rus, links=no, Великий Новгород, t=Great Newtown, p=vʲɪˈlʲikʲɪj ˈnovɡərət), also known as just Novgorod (), is the largest city and administrative centre of Novgorod Oblast, Russia. It is one of the ol ...

, Russia. Balushkin did not explain why he chose this name but it may refer to the similarity in form of ''G. svetovidovi'', especially the long, pointed teeth, to the zander.

Species

The recognized species in this genus are: * '' Gvozdarus balushkini'' Voskoboinikova & Kellermann, 1993 * '' Gvozdarus svetovidovi'' Balushkin, 1989 (Naked-head toothfish)

Characteristics

''Gvozdarus'' notothens have an elongate, fusiform body which is broadest at the front. The head is widest at its rear with a flat and wide space between the eyes and a snout which is longer than the diameter of its eyes. They have large mouths which extends to the front of the pupil. The lower jaw protrudes slightly and both jaws have canine-like teeth with an inner patch near the jaw joint in the upper jaw. The largest known fish of this genus had a total length of .

Distribution, habitat and biology

''Gvozdarus'' notothens are found in the Southern Ocean and the genus has a circumpolar distribution. The contents of the stomach of the

holotype A holotype is a single physical example (or illustration) of an organism, known to have been used when the species (or lower-ranked taxon) was formally described. It is either the single such physical example (or illustration) or one of several ...

consisted of the remains, including a lower mandible, of the

Antarctic silverfish The Antarctic silverfish (''Pleuragramma antarctica''), or Antarctic herring, is a species of marine ray-finned fish belonging to the family Nototheniidae, the notothens or cod icefishes. It is native to the Southern Ocean and the only truly pela ...

(''Pleuragramma antarcticum''). The Antarctic silverfish is the most abundant pelagic fish found over the

continental shelves A continental shelf is a portion of a continent that is submerged under an area of relatively shallow water, known as a shelf sea. Much of these shelves were exposed by drops in sea level during glacial periods. The shelf surrounding an island ...

of the Antarctic and this is taken to be an indication that these fishes are pelagic piscivores.

References

{{Taxonbar, from=Q2459747 Nototheniidae