Summary
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 waters around Antarctica.
| Notothenia | |
|---|---|
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| Notothenia coriiceps | |
Scientific classification 
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| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Actinopterygii |
| Order: | Perciformes |
| Family: | Nototheniidae |
| Genus: | Notothenia J. Richardson, 1844 |
| Type species | |
| Notothenia coriiceps J. Richardson, 1844
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| Synonyms[1] | |
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Taxonomy edit
Notothenia was first formally described as a genus in 1844 by the Scottish naval surgeon, naturalist and Arctic explorer John Richardson when he described N. coriiceps which was later designated as the type species of the genus.[1] Some authorities place this taxon in the subfamily Nototheniinae,[2] but the 5th edition of Fishes of the World does not include subfamilies in the Nototheniidae.[3] The name of the genus is a compound of notos meaning “south” and thenia which means “coming from”, an allusion to the high southern latitudes these fishes are found at.[4]
Species edit
Seven recognized species are in this genus:[5]
- Notothenia angustata F. W. Hutton, 1875 (Maori chief)
- Notothenia coriiceps J. Richardson, 1844 (black rockcod)
- Notothenia cyanobrancha J. Richardson, 1844 (blue rockcod)
- Notothenia microlepidota F. W. Hutton, 1875 (black cod)
- Notothenia neglecta Nybelin, 1951 (yellowbelly rockcod)
- Notothenia rossii J. Richardson, 1844 (marbled rockcod)
- Notothenia trigramma Regan, 1913
Characteristics edit
Notothenia fishes have oblong bodies which are compressed towards the tail with a large head, small eyes and a large mouth. The lower jaw does not protrude and the mouth extends as far back as the middle of the eye. There are moderately sized teeth in the jaws with no large canine-like teeth. There are two lateral lines consisting of tubed scales, one on the upper body and the other on the mid-flank. Most of the scales on the body are smooth while much of the head is naked. The pectoral fins are notably larger than the pelvic fins while the caudal fin may be rounded, truncate one emarginate.[2] They vary in maximum total length from 30 cm (12 in) in the blue rockcod to 92 cm (36 in) in the marbled rockcod.[5]
Distribution and habitat edit
Notothenia rockcods are found in the Southern Ocean where there are four species with two species in the southwestern Pacific Ocean and a single species in the southwestern Atlantic Ocean.[5] The young fish are pelagic and the adults are benthic.[2]
Biology edit
Notothenia rockcods have some adaptations that allow them to thrive in such inhospitable habitat, like antifreeze proteins in their blood[6] and ample fat to insulate them against heat loss and to offset their lack of a swim bladder.[7] They are benthic predators feeding on invertebrates and smaller fishes, although algae are consumed in large quantities too. The pelagic fingerlings allow the wide dispersal of the species around the Southern Ocean.[2]
Fisheries edit
Notothenia rockcods are targeted by some fisheries, with N. rossi being an important commercially fished species.[2]
References edit
- ^ a b Eschmeyer, William N.; Fricke, Ron & van der Laan, Richard (eds.). "Genera in the family Nototheniidae". Catalog of Fishes. California Academy of Sciences. Retrieved 23 September 2021.
- ^ a b c d e H.H. Dewitt; P.C. Heemstra; and O. Gon (1990). "Nototheniidae Notothens". In O. Gon and P.C. Heemstra (eds.). Fishes of the Southern Ocean. South African Institute for Aquatic Biodiversity. ISBN 9780868102115.
- ^ J. S. Nelson; T. C. Grande; M. V. H. Wilson (2016). Fishes of the World (5th ed.). Wiley. p. 465. ISBN 978-1-118-34233-6.
- ^ Christopher Scharpf & Kenneth J. Lazara, eds. (12 April 2021). "Order Perciformes: Suborder Notothenoididei: Families Bovichtidae, Pseaudaphritidae, Elegopinidae, Nototheniidae, Harpagiferidae, Artedidraconidae, Bathydraconidae, Channichthyidae and Percophidae". The ETYFish Project Fish Name Etymology Database. Christopher Scharpf and Kenneth J. Lazara. Retrieved 23 September 2021.
- ^ a b c Froese, Rainer and Pauly, Daniel, eds. (2014). Species of Notothenia in FishBase. February 2014 version.
- ^ Zulema L. Coppes Petricorena; George N. Somero (2006). "Biochemical adaptations of notothenioid fishes: Comparisons between cold temperate South American and New Zealand species and Antarctic species". Comparative Biochemistry and Physiology A. 147 (3): 799–807. doi:10.1016/j.cbpa.2006.09.028. PMID 17293146.
- ^ Joseph T. Eastman and Arthur L. DeVries (1982). "Buoyancy Studies of Notothenioid Fishes in McMurdo Sound, Antarctica". Copeia. 1982 (2): 385–393. doi:10.2307/1444619. JSTOR 1444619.