Nototheniidae

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{{Taxobox | color = pink | name = Cod icefishes | regnum = Animalia | phylum = Chordata | classis = Actinopterygii | ordo = Perciformes | subordo = Notothenioidei | familia = Nototheniidae | subdivision_ranks = Genera | subdivision = Aethotaxis
Cryothenia
Dissostichus
Gobionotothen
Gvozdarus
Lepidonotothen
Notothenia
Pagothenia
Paranotothenia
Patagonotothen
Pleuragramma
Trematomus
See text for species. }}

The cod icefishes are a family, Nototheniidae, of Perciform fishes, containing about 50 species in 12 genera. They are largely found in the Southern Ocean and off the coast of Antarctica. As the dominant Antarctic fish taxa, they occupy both sea bottom and water column ecological niches. Although lacking a gas bladder, they have undergone a depth-related diversification, such as increase in fatty tissues and reduced mineralization of the bones, resulting in a body density approaching neutral, to fill a variety of water column niches. As the chilly subantarctic waters averages –1 to 4 degrees Celsius, most Antarctic species have antifreeze proteins in their blood and other body fluids.

Some species exhibit morphism, for example, the circum-Antarctic Trematomus newnesi exists as two morphs in the Ross Sea, the typical morph and a large mouth/broad headed morph.

As the major fish resource in the Southern Ocean, nototheniids are under increasing pressure from commercial fishing.

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