''Nototheniops'' 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. The species in this genus are 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

''Nototheniops'' Was first formally described as a

subgenus In biology, a subgenus (plural: subgenera) is a taxonomic rank directly below genus. In the International Code of Zoological Nomenclature, a subgeneric name can be used independently or included in a species name, in parentheses, placed between t ...

of the genus '' Lepidonotothen'' in 1976 by the

Soviet The Soviet Union,. officially the Union of Soviet Socialist Republics. (USSR),. was a List of former transcontinental countries#Since 1700, transcontinental country that spanned much of Eurasia from 1922 to 1991. A flagship communist state, ...

ichthyologist Ichthyology is the branch of zoology devoted to the study of fish, including bony fish ( Osteichthyes), cartilaginous fish (Chondrichthyes), and jawless fish (Agnatha). According to FishBase, 33,400 species of fish had been described as of Octobe ...

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 ...

. The genus has been considered to be

monotypic 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 ...

by some authorities with ''N. larseni'' as the only species. Some authorities place this genus 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 ...

Nototheniinae, 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 specific name is a compound of ''

Notothenia ''Notothenia'' is a genus of marine ray-finned fishes belonging to the family Nototheniidae, the notothens or cod icefishes with the species in this genus often having the common name of rockcod. They are native to the Southern Ocean and other wa ...

'', which this genus is closely related to and ''ops'' meaning “eyes” referring to its larger eyes.

Species

The recognized species in this genus are: * '' Nototheniops larseni'' ( Lönnberg, 1905) * '' Nototheniops loesha'' (Balushkin 1976) * ''

Nototheniops nybelini ''Nototheniops'' is a genus of marine ray-finned fishes belonging to the family Nototheniidae, the notothens or cod icefishes. The species in this genus are native to the Southern Ocean. Taxonomy ''Nototheniops'' Was first formally described as ...

'' ( Balushkin, 1976) * ''

Nototheniops tchizh ''Nototheniops'' is a genus of marine ray-finned fishes belonging to the family Nototheniidae, the notothens or cod icefishes. The species in this genus are native to the Southern Ocean. Taxonomy ''Nototheniops'' Was first formally described as ...

'' (Balushkin, 1976)

Characteristics

''Nototheniops'' differs from the closely related ''Lepidonotothen'' and ''

Lindbergichthys ''Lindbergichthys'' is a genus of marine ray-finned fishes belonging to the family Nototheniidae, the notothens or cod icefishes. Froese, R. and D. Pauly. Editors. (2021). FishBase. Lindbergichthys Balushkin, 1979. Accessed through: World Registe ...

'' by having the area to front of the eye. the preorbital, and the snout scaled with unscaled eyes. There is a single

lateral line The lateral line, also called the lateral line organ (LLO), is a system of sensory organs found in fish, used to detect movement, vibration, and pressure gradients in the surrounding water. The sensory ability is achieved via modified epithelial ...

, the upper one, which consists of tubed scales. The

pectoral fin Fins are distinctive anatomical features composed of bony spines or rays protruding from the body of a fish. They are covered with skin and joined together either in a webbed fashion, as seen in most bony fish, or similar to a flipper, as ...

s are roughly equal in length or longer than the

pelvic fin Pelvic fins or ventral fins are paired fins located on the ventral surface of fish. The paired pelvic fins are homologous to the hindlimbs of tetrapods. Structure and function Structure In actinopterygians, the pelvic fin consists of two en ...

s. The first and second spines of the first

dorsal fin A dorsal fin is a fin located on the back of most marine and freshwater vertebrates within various taxa of the animal kingdom. Many species of animals possessing dorsal fins are not particularly closely related to each other, though through conv ...

are roughly equal in height but are taller than the third spine. The last spine of the first dorsal fin is connected to the first ray of the second dorsal fin by a membrane. There are 14-15 branch fin rays in the

caudal fin Fins are distinctive anatomical features composed of bony spines or rays protruding from the body of a fish. They are covered with skin and joined together either in a webbed fashion, as seen in most bony fish, or similar to a flipper, as se ...

. The front of the jaws have a band of small, sharp, conical teeth which reduces to a single series towards the rear of the jaws becoming uniserial, these back teeth and the outer row of the front teeth are a little bigger than the inner row. The largest recorded

total length Fish measurement is the measuring of individual fish and various parts of their anatomies. These data are used in many areas of ichthyology, including taxonomy and fisheries biology. Overall length * Standard length (SL) is the length of a fish ...

in this genus is in ''N. larseni''.

Distribution, habitat and biology

''Nototheniops'' are found in the Southern Ocean off the

Antarctic Peninsula The Antarctic Peninsula, known as O'Higgins Land in Chile and Tierra de San Martín in Argentina, and originally as Graham Land in the United Kingdom and the Palmer Peninsula in the United States, is the northernmost part of mainland Antarctic ...

and in the subantarctic islands and seamounts, especially in the Atlantic and Indian sectors. They are found at depths between . The larvae and juveniles are

pelagic The pelagic zone consists of the water column of the open ocean, and can be further divided into regions by depth (as illustrated on the right). The word ''pelagic'' is derived . The pelagic zone can be thought of as an imaginary cylinder or wa ...

and it is thought they may have a long pelagic phase which helps dispersal, settling to a

benthic The benthic zone is the ecological region at the lowest level of a body of water such as an ocean, lake, or stream, including the sediment surface and some sub-surface layers. The name comes from ancient Greek, βένθος (bénthos), meaning "t ...

lifestyle as adults. They feed on

crustaceans Crustaceans (Crustacea, ) form a large, diverse arthropod taxon which includes such animals as decapods, seed shrimp, branchiopods, fish lice, krill, remipedes, isopods, barnacles, copepods, amphipods and mantis shrimp. The crustacean group ...

such as

krill Krill are small crustaceans of the order Euphausiacea, and are found in all the world's oceans. The name "krill" comes from the Norwegian Norwegian, Norwayan, or Norsk may refer to: *Something of, from, or related to Norway, a country in n ...

, hyperiid amphipods and

mysid Mysida is an order of small, shrimp-like crustaceans in the malacostracan superorder Peracarida. Their common name opossum shrimps stems from the presence of a brood pouch or "marsupium" in females. The fact that the larvae are reared in thi ...

s, juveniles feeding on

copepods Copepods (; meaning "oar-feet") are a group of small crustaceans found in nearly every freshwater and saltwater habitat. Some species are planktonic (inhabiting sea waters), some are benthic (living on the ocean floor), a number of species have p ...

References

{{Taxonbar, from=Q675148 Nototheniidae