Snoek

Snoek
	Snoek ( Thyrsites atun )
Systematics
	Spinefish (Acanthopterygii)
	Perch relatives (Percomorphaceae)
Order :	Scombriformes
Family :	Mackerel (Gempylidae)
Genre :	Thyrsites
Type :	Snoek
Scientific name of the genus
	Thyrsites
	Lesson , 1831
Scientific name of the species
	Thyrsites atun
	( Euphrases , 1791)

The snoek ( Thyrsites atun ), pronounced 'snuk', actually snoek-makreel, "pike mackerel" ( Afrikaans or Dutch) belongs to the snake mackerel (Gempylidae). It can grow up to 2 m long and up to 10 years old, but is so slim and flattened on the sides that it then weighs just over 6 kg. Nevertheless, it is an important, sought-after and therefore endangered food fish in the southern hemisphere. The genus Thyrsites is monotypical .

Appearance

The Snoek is even slimmer than the Escolar . The head and torso are blue-silver, the back darker than the sides. Its head is long and pointed, the lower jaw significantly longer than the upper jaw. The black first dorsal fin is five times as long as the soft rayed second. This is triangular like the anal fin of the same size, followed by 6 or 7 flippers. The pelvic fins are very small.

The jawbite shows a dense series of long, curved fangs, especially in the front of the upper jaw - in this respect it is very similar to that of Macrodon ancylodon from the Umberfish family , whose food consists mainly of swimming (and sitting) crabs. This dentition obviously allows an interpretation of the scientific name Thyrsites (coined by Lesson 1831, adopted by Cuvier 1832). " Thyrsites " looks like a derivation of ϑύρσος, a "plant stem" (and attribute of the Bacchantes - which doesn't make any sense) - or like a spelling mistake or an allusion to Θερσίτης ( Thersites ), the "ugliest Greeks before Troy: pointed , loud-mouthed and cross-eyed "; atύn is a Spanish form of "tuna".

Fin formula : D1 XVIII-XX, D2 I / 11-13, AI / 9-11, P approx. 13, VI / 4-5.- 35 vertebrae.

Distribution and way of life

The Snoek was first known from the sea off South Africa , but it is present in the southern temperate ocean (12-18 ° C) around the globe, including Tierra del Fuego , Patagonia , southern Chile , New Zealand (where it is called "Barracouta") ), Tasmania , New South Wales , from the oceanic islands (the northernmost appears to be St. Helena ) and over the undersea mountains of this zone, the southern limit of which is about 56 ° S. Apparently there are quite a few populations.

It lives in swarms at depths of 0 to 450 m (the eyes are not quite as large as in the genera that penetrate further into the depths), i.e. epi- (especially at night) to bathy pelagic . Its diet consists - in addition to the crustaceans mentioned (here especially krill (Euphausiacea)) - also from fish, especially from herring-like fish , squid and others.

Sale of Thyrsites atun in Cape Town

use

The Snoek is fished everywhere (also as a sport) and is therefore endangered. In South Africa the South African fur seal ( Arctocephalus pusillus ) is suspected of eating “too much pike”. In 1978 the South Africans “harvested” 81,000 t of “snoeken”, but since then the yield has decreased to around 20,000 t per year. In 1999 the Food and Agriculture Organization reported the total catch of 41,472 t (New Zealand 20,642 t, South Africa 11,188 t). Smoked Snoek (in bundles) is particularly popular, but it is equally suitable for almost any form of preparation.

literature

Marc H. Griffiths: Life history of South African snoek, Thyrsites atun (Pisces: Gempylidae): a pelagic predator of the Benguela ecosystem. In: Fishery Bulletin. Vol. 100, No. 4, 2002, ISSN 0099-5487 , pp. 690-710, ( digital version (PDF; 1.19 MB) ).

Richard Thomas Lowe : A History of the Fishes of Madeira. Quaritch, London 1843, pp. 141 f. , (Carries out a long discussion about the delimitation of thyrsites - today as well as other monotypical genres predominate here , which takes the purpose of the binomials ad absurdum ).

Izumi Nakamura, Nikolaj V. Parin: Snake mackerels and cutlassfishes of the world. An annotated and illustrated catalog of the Snake Mackerels, Snoeks, Escolars, Gemfishes, Sackfishes, Domine, Oilfish, Cutlassfishes, Scabbardfishes, Hairtails, and Frostfishes known to date (= FAO Species Catalog. Vol. 15 = FAO Fisheries Synopsis. No. 125 , Vol. 15). Food and Agriculture Organization of the United Nations, Rome 1993, ISBN 92-5-103124-X .

Web links

Commons : Snoek ( Thyrsites atun ) - collection of images, videos and audio files

Snoek on Fishbase.org (English)
Thyrsites atun at www.itis.gov (accessed January 2, 2010)

supporting documents

↑ Bengt Anders Euphrasen, 1756-1797 (1796?), Swedish naturalist (botanist and zoologist), wrote e.g. B. about plagiostomas.
↑ AnAge entry in www.genomics.senescence.info (English, accessed on January 2, 2010).
↑ Homer , Iliad B 212, 216, 219.
↑ Occurrence overview at data.gbif.org (English, accessed on January 2, 2010).
^ Maurice Blackburn: The Relation Between the Food of the Australian Barracouta, Thyrsites atun (Euphrasen), and Recent Fluctuations in the Fisheries. In: Australian Journal of Marine and Freshwater Research. Vol. 8, No. 1, 1957, ISSN 0067-1940 , pp. 29-54, doi : 10.1071 / MF9570029 .
↑ Species Fact Sheets at www.fao.org (accessed January 2, 2010).

[1] Bengt Anders Euphrasen, 1756-1797 (1796?), Swedish naturalist (botanist and zoologist), wrote e.g. B. about plagiostomas.

[2] AnAge entry in www.genomics.senescence.info (English, accessed on January 2, 2010).

[3] Homer , Iliad B 212, 216, 219.

[4] Occurrence overview at data.gbif.org (English, accessed on January 2, 2010).

[5] Maurice Blackburn: The Relation Between the Food of the Australian Barracouta, Thyrsites atun (Euphrasen), and Recent Fluctuations in the Fisheries. In: Australian Journal of Marine and Freshwater Research. Vol. 8, No. 1, 1957, ISSN 0067-1940 , pp. 29-54, doi : 10.1071 / MF9570029 .

[6] Species Fact Sheets at www.fao.org (accessed January 2, 2010).