Euthynnus alletteratus (Rafinesque 1810)

Die Atlantiese kleintuna (Euthynnus alletteratus) is 'n vis wat voorkom aan die kus van Angola. In Engels staan die vis bekend as die Atlantic little tuna.

Sien ook

• Alfabetiese lys van visse
• Lys van Suider-Afrikaanse visse volgens wetenskaplike name
• Lys van varswater visfamilies
• Lys van visfamilies

Bron

• Coastal Fishes of Southern Africa. Phil & Elaine Heemstra. 2004. ISBN 1-920033-01-7

Verwysings

Eksterne skakel

• http://www.fishbase.org/summary/Euthynnus-alletteratus.html

Hierdie artikel is ’n saadjie. Voel vry om Wikipedia te help deur dit uit te brei.

Euthynnus alletteratus ye una especie de pexes de la familia Scombridae nel orde de los Perciformes.

Morfoloxía

• Los machos pueden llegar algamar los 122 cm de llargor total y los 16,5 kg de pesu.^[1]

Distribución xeográfica

Alcuéntrase nos mares y océanos tropicales y subtropicales, incluyendo'l Mar Mediterraneu, el Mar Negru, el Mar Caribe y el Golfu de Méxicu

Referencies

Bibliografía

• El léxico de la fauna marina en los puertos pesqueros de Asturias Central, Emilio Barriuso, Uviéu 1986. IDEA.
  
• Fenner, Robert M.: The Conscientious Marine Aquarist. Neptune City, Nueva Jersey, Estaos Xuníos : T.F.H. Publications, 2001.
• Helfman, G., B. Collette y D. Facey: The diversity of fishes. Blackwell Science, Malden, Massachusetts, Estaos Xuníos , 1997.
• Hoese, D.F. 1986: . A M.M. Smith y P.C. Heemstra (eds.) Smiths' seya fishes. Springer-Verlag, Berlín, Alemaña.
• Maugé, L.A. 1986. A J. Daget, J.-P. Gosse y D.F.Y. Thys van dean Audenaerde (eds.) Check-list of the freshwater fishes of Africa (CLOFFA). ISNB Bruxeles; MRAC, Tervuren, Flandes; y ORSTOM, París, Francia. Vol. 2.
• Moyle, P. y J. Cech.: Fishes: An Introduction to Ichthyology, 4a. edición, Upper Saddle River, Nueva Jersey, Estaos Xuníos: Prentice-Hall. Añu 2000.
• Nelson, J.: Fishes of the World, 3a. edición. Nueva York, Estaos Xuníos: John Wiley and Sons. Añu 1994.
• Wheeler, A.: The World Encyclopedia of Fishes, 2a. edición, Londres: Macdonald. Añu 1985.
• 
  

Enllaces esternos

• Animal Diversity Web (n'inglés)
• AQUATAB.NET[1]

La Bacoreta (Euthynnus alletteratus) és una espècie de peix de la família dels escòmbrids i de l'ordre dels perciformes.

Morfologia

Els mascles poden assolir els 122 cm de longitud total i els 16,5 kg de pes.^[3]

Distribució geogràfica

Es troba als mars i oceans tropicals i subtropicals, incloent-hi la Mar Mediterrània, la Mar Negra, el Carib i el Golf de Mèxic.^[3]

Referències

Bibliografia

• Collette, B.B. i C.E. Nauen, 1983. FAO species catalogue. Vol. 2. Scombrids of the world. An annotated and illustrated catalogue of tunas, mackerels, bonitos and related species known to date. FAO Fish. Synop. 125(2). 137 p.
• Helfman, G., B. Collette i D. Facey: The diversity of fishes. Blackwell Science, Malden, Massachusetts (Estats Units), 1997.
• Moyle, P. i J. Cech.: Fishes: An Introduction to Ichthyology, 4a edició, Upper Saddle River (Nova Jersey, Estats Units): Prentice-Hall. Any 2000.
• Nelson, J.: Fishes of the World, 3a edició. Nova York, Estats Units: John Wiley and Sons. Any 1994.
• Rafinesque, C. S. 1810. Caratteri di alcuni nuovi generi e nuove specie di animali e piante della sicilia, con varie osservazioni sopra i medisimi. (Part 1 involves fishes, pp. [i-iv] 3-69 [70 blank], Part 2 with slightly different title, pp. ia-iva + 71-105 [106 blank]). Caratteri. Pls. 1-20.
• Wheeler, A.: The World Encyclopedia of Fishes, 2a edició, Londres: Macdonald. Any 1985.

Enllaços externs

• Animal Diversity Web (anglès)
• AQUATAB.NET

Pysgodyn sy'n byw yn y môr ac sy'n perthyn i deulu'r Scombridae ydy'r tiwna bach sy'n enw gwrywaidd; lluosog: tiwnaod bach (Lladin: Euthynnus alletteratus; Saesneg: Little tunny).

Mae ei diriogaeth yn cynnwys America ac mae i'w ganfod ym Môr y Gogledd ac arfordir Cymru.

Ar restr yr Undeb Rhyngwladol dros Gadwraeth Natur (UICN), caiff y rhywogaeth hon ei rhoi yn y dosbarth 'Lleiaf o Bryder' o ran niferoedd, bygythiad a chadwraeth.^[1]

Gweler hefyd

• Rhestr o greaduriaid morol gwledydd Prydain
• Rhestr Goch yr IUCN, rhestr o greaduriaid wedi'u dosbarthu i 9 categori yn ôl niferoedd, prinder, cadwraeth ayb.
• Llwybr yr Arfordir
• Cadwraeth

Cyfeiriadau

• Gwefan Llên Natur; termau safonol.

Tuňák malý je nejběžnější druh tuňáka v Atlantském oceánu. Constantine Samuel Rafinesque popsal tuňáka malého v roce 1810 a dal mu jeho jméno: Euthynnus alletteratus.

Popis

Tuňák malý má malé tělo i ve srovnání s ostatními druhy tuňáků. Má pevné proudnicové tělo usnadňující mu prudce zvýšit rychlost ale i vytrvale plavat. Má velká ústa s pevnými čelistmi a trochu vyčnívající dolní čelist s jednou řadou malých dovnitř zahnutých špičatých patrových zoubků. Zuby chybí na radličné kosti a jazyk je podélně dvojitě vystouplý.

Rypec je kratší než zbytek těla. Hřbetní ploutev má 10 až 15 sestupně dlouhých trnů, které po krátké mezeře pokračují menšími paprsky ve druhé hřbetní ploutvi následované osmi ploutvičkami. Řitní ploutev má 11 až 15 nepatrně zřetelných paprsků, následované sedmi ploutvičkami. Prsní ploutve jsou krátké a nedosahují konce první hřbetní ploutve a jsou spojeny s břišní ploutví břišními výrůstky. Má 37 až 45 žaberních tyčinek – kostnaté výběžky na prvním žaberním oblouku.

Tělo je bez šupin s výjimkou oblasti postranní čáry a korzetu, silného pásu šupin obkružujícího tělo.

Zbarvení

Zbarvení je typicky kovově modré nebo modrozelené s tmavými zvlněnými pruhy nad postranní čarou. Pruhy jsou zřetelně ohraničeny a nikdy nezasahují dále než do střední úrovně první hřbetní ploutve. Břicho je světle bílé se třemi až sedmi tmavými skvrnami v oblasti prsní a břišní ploutve.

Tuňák malý bývá díky svému zbarvení zaměňován s pelamidou obecnou, ale liší se barevným vzorováním i celkovými rozměry těla.

Ve Středozemním moři dosahuje maximální váhy 12 kg, s průměrem kolem 7 kg. Jeho maximální délka (FL) je ve Středozemním moři kolem 100 cm a v Atlantiku je kolem 90 cm. Průměrná délka (FL) dospělých ryb je 85 cm. Některé ryby mohou dorůstat délky 100 cm a více, ale nejčastěji mají délku kolem 64 cm. Největší zaznamenaný tuňák malý měl 120 cm a 17 kg. Samice dosahují dospělosti při délce (FL) 27 až 37 cm, zatímco samci dospívají kolem délky 40 cm.

Význam

Tuňák malý je hospodářsky významná ryba.

Reference

1. ↑ Červený seznam IUCN 2018.1. 5. července 2018. Dostupné online. [cit. 2018-08-10]

Externí odkazy

• Obrázky, zvuky či videa k tématu tuňák malý ve Wikimedia Commons
• Galerie tuňák malý ve Wikimedia Commons
• BioLib.cz – Euthynnus alletteratus (tuňák malý) [online]. BioLib.cz. Dostupné online.
• Euthynnus alletteratus : fisheries, aquaculture, gamefish [online]. Příprava vydání Rainer Froese, Daniel Pauly. FishBase, 2014. Dostupné online. (anglicky)

Die Thonine (Euthynnus alletteratus) oder Kleiner Thun ist ein maximal bis 1,20 Meter und 16 Kilogramm schwerer Schwarmfisch.

Verbreitung

Die Thonine lebt im subtropischen und tropischen Atlantik in der Nähe der Küsten. Im Ostatlantik reicht ihr Verbreitungsgebiet von der Küste der Iberischen Halbinsel bis nach Angola. Sie lebt auch im Mittelmeer, und im Zentralatlantik bei den Azoren. Im Westatlantik lebt sie von der Küste North Carolinas bis nach Brasilien, in der Karibik und im östlichen Golf von Mexiko.

Merkmale

Sie wird für gewöhnlich etwa 80 cm lang und hat die typischen 7 bis 8 Flössel zwischen Rücken- bzw. Afterflosse und Schwanzflosse. Kennzeichnend für die Art ist der gestreifte Rücken und die 3 bis 7 dunklen Flecken zwischen Brust- und Bauchflossen. Die ersten Strahlen der ersten Rückenflosse sind sehr viel höher als die folgenden, so dass die Flosse eine konkave Form hat. Der Abstand zwischen erster und zweiter Rückenflosse ist gering. Die Region hinter dem Kopf und um die Brust- und Bauchflossen wird von einem Korsett aus großen, dicken Schuppen bedeckt. Der Rest des Körpers, mit Ausnahme der Seitenlinie, ist unbeschuppt. Die Anzahl der Wirbel liegt bei 39. Eine Schwimmblase fehlt.

• Flossenformel: Dorsale XV–XVI/11–13, Anale 0/11–15.

Lebensweise

Die Thonine lebt in Schwärmen in Küstennähe und ernährt sich von kleinen Schwarmfischen, vor allem von Hering, aber auch von Krebstieren, Kopffüßern, pelagischen Schnecken und Manteltieren. Eier und Larven sind pelagisch.

Nutzung

Die Thonine ist kein bedeutender Speisefisch und ist eher ein zufälliger Beifang.

Literatur

• Bent J. Muus, Jørgen G. Nielsen: Die Meeresfische Europas in Nordsee, Ostsee und Atlantik. Kosmos, Stuttgart 1999, ISBN 3-440-07804-3.

Weblinks

– Sammlung von Bildern, Videos und Audiodateien

• Thonine auf Fishbase.org (englisch)
• Euthynnus alletteratus in der Roten Liste gefährdeter Arten der IUCN 2013.1. Eingestellt von: Collette, B., Amorim, A.F., Boustany, A., Carpenter, K.E., de Oliveira Leite Jr., N., Di Natale, A., Fox, W., Fredou, F.L., Graves, J., Viera Hazin, F.H., Juan Jorda, M., Kada, O., Minte Vera, C., Miyabe, N., Nelson, R., Oxenford, H., Teixeira Lessa, R.P. & Pires Ferreira Travassos, P.E., 2010. Abgerufen am 16. September 2013.

The little tunny (Euthynnus alletteratus), also known as the false albacore, little tuna, bonita, or erroneously as the blue bonito, is a species of tuna in the family Scombridae. It can be found in the Atlantic Ocean and the Mediterranean and Black seas; in the western Atlantic, it ranges from Brazil to the New England states. The little tunny is a pelagic fish that can be found regularly in both offshore and inshore waters, and it is classified as a highly migratory species.^[3][4] The little tunny is best identified by the "worm-like" markings on its back and the dark spots appearing between its pectoral and ventral fins.^[5]

Commercially, the fish is used as bait for sharks and marlin due to its high oil content and hook retention. Because of its strong "fishy" taste and the considerable effort required to prepare it, the little tunny is considered by many to be a rough fish and is not commonly eaten.^[6][7] However, it is sought after as a sport fish due to its line-stripping 64 km/h (40 mph) runs and hard fighting ability when hooked. By trolling with lures near reefs, it can be caught on hook and line.^[6]

Taxonomy

Constantine Samuel Rafinesque identified the little tunny in 1810 and gave the fish its current name, Euthynnus alletteratus. Synonyms for used for the name include E. alleteratus alleteratus, E. alliteratus, E. thunina, and E. alletteratus aurolitoralis.^[6] The little tunny is not part of the genus Thunnus like many tuna, but it is part of the tribe Thunnini.

Description

The little tunny is small in body size compared to other tuna species. It has a compact and stream-lined body built to facilitate bursts of speed, as well as endurance while swimming. Its torpedo-shaped, robust body is made for powerful swimming.^[6] It has a large mouth with rigid jaws and a slightly protruding lower jaw, with a single row of small, inwardly curved, cone-shaped teeth on the palate.^[8] Teeth are absent on the vomer, the small bone in the roof of the mouth,^[6] and the tongue has two longitudinal ridges.^[6]

A little tunny

The snout is shorter than the rest of the head. The little tunny has a dorsal fin with 10 to 15 tall, descending spines, as well as a much smaller second dorsal fin followed by eight finlets. At the base, the two dorsal fins are separated by a small interspace.^[8] The anal fin has 11 to 15 slightly defined rays, and is followed by seven finlets. The pectoral fins are short and do not reach the end of the first dorsal fin and are joined to the pelvic fins by interpelvic processes.^[6] There are 37-45 gill rakers, bony projections off the gills, on the first arch. There are no scales on the body of the little tunny except along the lateral line and on the corselet: a thick band of scales circling the body.^[6][9]

The coloration of the little tunny is typically metallic blue or blue-green with dark, wavy stripes above the lateral line. These "worm-like" lines are within a well-marked border that never extends farther forward than the middle of the first dorsal fin.^[8] The belly is bright white with three to seven dark, fingerprint-like spots around the pectoral and pelvic fins. The little tunny is commonly confused with the Atlantic bonito because of coloration, but the two fish differ in their color patterns and overall body size.

The little tunny's markings allow it to easily be distinguished from similar species. It is often confused with the skipjack tuna, the frigate tuna, the Atlantic bonito, and the bullet tuna. Close relatives also include the kawakawa and the black skipjack. The scattering of dark, fingerprint-like spots between the pectoral and pelvic fins cannot be found on any related Atlantic species. The first dorsal fin of the Atlantic bonito is also lower and sloping. Its lack of teeth on the vomer can set it apart from its close Pacific relatives, the kawakawa and the black skipjack. The dorsal fins of the bullet and frigate mackerel are set apart. Unlike the little tunny, the skipjack tuna lacks markings on the back and has broad, straight stripes on the underside.^[10]

The little tunny reaches a maximum weight of 12 kg (26 lb) in the Mediterranean, and averages about 7 kg (15 lb) through its entire range. Its maximum fork length (distance from the tip of the snout to the fork of the tail) in the Mediterranean is about 100 cm (39 in) and in the Atlantic is about a 90 cm (35 in).^[11] Average fork length for an adult fish throughout the entire range is about 85 cm (33 in).^[12] Some fish may reach a length of 100 cm (39 in) or more, but most commonly they are around 64 cm (25 in). The largest little tunny on record is 120 cm (47 in) and 17 kg (37 lb).^[13] Females reach sexual maturity at 27 to 37 cm (11–15 in) in fork length, while males mature at about 40 cm (16 in).^[6]

Anatomy

The little tunny has some anatomical variations when compared to other species of Euthynnus. E. alletteratus lacks a swim bladder, like most other tuna, so it must constantly keep moving to stay afloat. The pectoral fins are crucial to the little tunny in maintaining its position in the water column. Its liver is very disproportionate, with the right lobe much longer than the left or middle lobes. The stomach of the little tunny is a long sac that stretches almost the entire length of its body. The intestinal tract is fairly short, coming from the left and right sides of the stomach, and extending without looping down the length of its body. The different sections are characterized by their diameter and color.^[14] The ventral vertebral column of the little tunny has unique trelliswork, which is important to its family (Scombridae). Divided haemapophyses, or parts of the vertebrate forming a long canal, enclose the large ventral blood vessel.^[15]

Feeding habits

A school of little tunny feeding

In coastal waters along the North American eastern seaboard, little tunny are carnivorous, and primarily feed on small fish and invertebrates that occur in schools. Its diet consists mostly of fish; it particularly likes the Atlantic bigeye and largehead hairtail. Second to fish, the little tunny consumes crustaceans, and lastly cephalopods and gastropods make up a small part of its diet. Sardines, scad, and anchovies are common in the diet along with squid, stomatopods, and organisms from the family Diogenidae. The diet of the fish is also relative to its size. A smaller fish's diet typically consists of clupeiforms, and larvae, while the larger fish mostly eat Maurolicus muelleri. The typical diet is very similar to that of the king mackerel because the fish are of a similar size and live in the same area of the water column.^[16] The little tunny is an opportunistic predator, feeding on crustaceans, clupeid fishes, squids, and tunicates. Its diet also responds to seasonal changes in food availability. There is conflicting evidence on if the little tunny is a nocturnal or diurnal feeder.^[17] It is a specialist feeder, often feeding on herring and sardines in inshore waters near the surface of the water.^[6] The little tunny commonly feeds in large schools because their primary food sources (small fish and the larval forms of crustaceans) are typically in schools, as well.

Distribution and habitat

The little tunny is found in the neritic waters of the temperate and tropical zones in the Atlantic ocean. It can also be found in the waters of the Mediterranean Sea and the Black Sea. In the eastern Atlantic, the little tunny has been found from Skagerrak to South Africa. Although found it this broad range of latitudes, it is rare north of the Iberian Peninsula or farther south than Brazil. On the Atlantic coast of the United States, they can be caught as far north as Cape Cod, Massachusetts, and as far south as the tip of Florida, as well as throughout the waters of the Gulf of Mexico.^[18]

The little tunny's habitat tends to be near-shore waters, much closer to shore than most other tunas. They live in and around inlets, points, jetties, and sandbars. All of these places are where bait fish like sardine and menhaden, both favorites of the little tunny, form large schools, which are very helpful to the little tunny's feeding style. While the little tunny is abundant in offshore ocean waters, it is unusual to find it in brackish water of estuaries. The very young will enter estuaries in South Africa.^[15] The little tunny prefers relatively warm water, from 24° to 30° Celsius. The little tunny migrates south in the winter and fall, and northward in the spring, through coastal waters. It is not as migratory as other tuna species.^[10]

The little tunny is typically a schooling species.^[15] It lives in schools based primarily on fish size rather than species, so other members of the family Scombridae, like the Atlantic bonito, may be present. These schools cover areas up to 3.2 kilometres long. Little tunny that have not yet reached adulthood form tight schools offshore. Larger schools are more common offshore whereas smaller groups may wander far inshore.

Reproduction

Little tunny spawn in water that is at least 25 °C (77 °F) in the months of April through November in the Atlantic Ocean. The spawning season of the little tunny in the Mediterranean is generally between May and September, but the most intensive spawning occurs between July and August. The major spawning areas are offshore, in waters that are 30 to 40 metres deep. The females are prolific fish, and can release 1.75 million eggs, in multiple clutches over a mating season.^[6] The eggs are fertilized in the water column after the males release sperm. The eggs are buoyant, spherical, transparent, and pelagic. A droplet of oil within the egg adds to its buoyancy. The diameter of the eggs can be anywhere from 0.8 mm to 1.1 mm, and they are light amber. Larvae are released 24 hours after fertilization and are approximately 3 mm in size. Pigmentation in the eyes appear 48 hours after hatching. The teeth and fins develop at sizes of 3.7–14 mm. Once the larvae are 14 mm to 174 mm long, they take on the adult appearance; the body becomes more elongated.^[19] Studies have found that it takes approximately 3 years for the little tunny's gonads to reach sexual maturity. The average size of a sexually mature individual is 38 cm (15 in) in fork length.^[20]

Predators and parasites

Bony fish, Marlins, sea birds, sharks, and rays prey on the little tunny.^[13] Other tunas, including conspecifics and yellowfin tuna (Thunnus albacares) are predators of the little tunny. Fish such as the dolphin fish (Coryphaena hippurus), wahoo (Acanthocybium solandri), Atlantic sailfish (Istiophorus albicans), swordfish (Xiphias gladius), and various sharks as well as other large marine carnivores all prey on the little tunny. Among those sharks is the whale shark, which feeds on the little tunny's recently spawned eggs. Seabirds prey on small little tunny.^[6]

At least 3 species of sea lice are known parasites of the little tunny, all of the Caligus genus. These are found on the body surface and the wall of the branchial cavities. Another copepod, Pseudocycnoides appendiculatus, is a known parasite of the gill filaments. Other parasites include Digenea (flukes), Monogenea (gillworms), Cestoda (tapeworms), and isopods.^[6]

Fishing

As with many inshore gamefish like bluefish and striped bass, schools of little tunny are usually indicated by flocks of birds diving in coastal waters. Fishermen targeting them often troll bait, cast lures, and float fish. When trolling for little tunny, fishermen often use small lures baited with either mullet or ballyhoo or lures dressed with colored feathers. When float fishing, popular baits are Spot, Bluefish, or Pinfish. Popular lures include deadly dicks, maria jigs, and other slender-profiled, brightly colored metal lures that can be cast far and retrieved quickly that imitate the small baitfish the little tunny are often feeding on. It is not uncommon for little tunny to be taken while shore fishing in the northern states along the East Coast of the United States, especially during late summer when the water near beaches is generally clear and easy for the fish to hunt in. Some anglers use little tunny for strip bait to catch other species, but most fish are released as the little tunny is not commonly thought of as a food fish. There is little regulation of the fishery, no size or bag limits, and no closed season. The flesh of the little tunny is coarse in texture, strong in flavor, and dark in color if compared to bluefin or yellowfin tuna.^[21]

The little tunny is also native to the entire Mediterranean, especially around Sicily and the Ionian Sea. They love warm waters and cover long distances during the spring and summer mating season. The tuna is caught with longlines, containment nets and drift nets. The highest catch quota is achieved from April to September. Before overfishing, large schools migrated to the upper Adriatic, where they were observed from the karst. The last major catch in this regard was made in 1954 in the Trieste area by fishermen from Santa Croce and Barcola.^[22]

References

Euthynnus alletteratus es una especie de peces de la familia Scombridae en el orden de los Perciformes.

Morfología

• Los machos pueden llegar alcanzar los 122 cm de longitud total y los 16,5 kg de peso.^[1]​

Distribución geográfica

Se encuentra en los mares y océanos tropicales y subtropicales, incluyendo el Mar Mediterráneo, el Mar Negro, el Mar Caribe y el Golfo de México

Referencias

Bibliografía

• Fenner, Robert M.: The Conscientious Marine Aquarist. Neptune City, Nueva Jersey, Estados Unidos : T.F.H. Publications, 2001.
• Helfman, G., B. Collette y D. Facey: The diversity of fishes. Blackwell Science, Malden, Massachusetts, Estados Unidos , 1997.
• Hoese, D.F. 1986: . A M.M. Smith y P.C. Heemstra (eds.) Smiths' sea fishes. Springer-Verlag, Berlín, Alemania.
• Maugé, L.A. 1986. A J. Daget, J.-P. Gosse y D.F.E. Thys van den Audenaerde (eds.) Check-list of the freshwater fishes of Africa (CLOFFA). ISNB Bruselas; MRAC, Tervuren, Flandes; y ORSTOM, París, Francia. Vol. 2.
• Moyle, P. y J. Cech.: Fishes: An Introduction to Ichthyology, 4a. edición, Upper Saddle River, Nueva Jersey, Estados Unidos: Prentice-Hall. Año 2000.
• Nelson, J.: Fishes of the World, 3a. edición. Nueva York, Estados Unidos: John Wiley and Sons. Año 1994.
• Wheeler, A.: The World Encyclopedia of Fishes, 2a. edición, Londres: Macdonald. Año 1985.

Lanpo bularpikarta (Euthynnus alletteratus) edo soilik atuntxikia (beste espezie batzuekin batera) Scombridae familiako ur gaziko arraina da, Ozeano Atlantikoan, Mediterraneo itsasoan eta Itsaso Beltzan bizi dena^[1].

Bermeon, Mundakan eta Lekeition albokera eta Ondarroan albakora diote.^[2]

Banaketa

Erreferentziak

Euthynnus alletteratus

La Thonine commune (Euthynnus alletteratus) est une espèce de poissons de la famille des scombridés.

Description et caractéristiques

Ce poisson mesure entre 60 et 122 cm de long, pour une moyenne de 80 centimètres. Le poids maximal est de 16,5 kg. Le dos (quart arrière-supérieur) porte des bandes obliques sombres sur un fond métallisé. Entre les nageoires pelvienne et anale, on compte également 3 à 7 taches sombres^[1].

Alimentation

Elle se nourrit principalement de petits poissons mais aussi de crustacés, de céphalopodes et de gastéropodes, selon un régime très opportuniste^[1].

Reproduction

Dans l'océan Atlantique, les thonines communes se reproduisent dans une eau d'au moins 25 °C entre avril et novembre. Dans la mer Méditerranée la saison de reproduction se déroule entre mai et septembre. La femelle peut pondre jusqu'à 1,75 million d'œufs durant une saison.

Prédateurs

La thonine commune est la proie du mahi-mahi (Coryphaena hippurus), du thazard noir (Acanthocybium solandri), du voilier de l'Atlantique (Istiophorus albicans), de l'espadon (Xiphias gladius) et de certains requins.

Références

• (fr+en) Référence FishBase :
• (en) Référence Catalogue of Life : Euthynnus alletteratus (Rafinesque, 1810) (consulté le 22 décembre 2020)
• (fr+en) Référence ITIS : Euthynnus alletteratus (Rafinesque, 1810)
• (en) Référence NCBI : Euthynnus alletteratus (Rafinesque, 1810) (taxons inclus)
• (en) Référence uBio : Euthynnus alletteratus (Rafinesque, 1810)
• (en) Référence Animal Diversity Web : Euthynnus alletteratus
• (en) Référence UICN : espèce Euthynnus alletteratus (consulté le 10 septembre 2021)
• (fr) Référence DORIS : espèce Euthynnus alletteratus
• (fr) Référence INPN : Euthynnus alletteratus (Rafinesque, 1810)

Notes et références

A merma^[1] ou bacoreta^[2] (Euthynnus alletteratus) é unha especie de peixe da familia Scombridae, da orde dos Perciformes, do grupo do túnidos.

Os machos poden chegar a medir 122 cm de lonxitude total e pesar 16,5 kg.^[3]

Encóntranse nos mares e océanos tropicais e subtropicais, incluíndo o mar Mediterráneo, o mar Negro, o mar Caribe e o golfo de México

Notas

Véxase tamén

Bibliografía

• Fenner, Robert M.: The Conscientious Marine Aquarist. Neptune City, Nova Jersey, Estados Unidos : T.F.H. Publications, 2001.
• Helfman, G., B. Collette e D. Facey: The diversity of fishes. Blackwell Science, Malden, Massachusetts, Estados Unidos , 1997.
• Hoese, D.F. 1986: . A M.M. Smith e P.C. Heemstra (eds.) Smiths' sea fishes. Springer-Verlag, Berlín, Alemaña.
• Maugé, L.A. 1986. A J. Daget, J.-P. Gosse e D.F.E. Thys van den Audenaerde (eds.) Check-list of the freshwater fishes of Africa (CLOFFA). ISNB Bruxelas; MRAC, Tervuren, Flandres; e ORSTOM, París, Francia. Vol. 2.
• Moyle, P. e J. Cech.: Fishes: An Introduction to Ichthyology, 4a. edición, Upper Saddle River, Nova Jersey, Estados Unidos: Prentice-Hall. Ano 2000.
• Nelson, J.: Fishes of the World, 3a. edición. Nova York, Estados Unidos: John Wiley and Sons. Ano 1994.
• Wheeler, A.: The World Encyclopedia of Fishes, 2a. edición, Londres: Macdonald. Ano 1985.

Il tonnetto o alletterato^[2] (Euthynnus alletteratus), conosciuto comunemente come tonnetto alletterato, è un pesce marino appartenente alla famiglia Scombridae.

Distribuzione e habitat

Questa specie è diffusa nel mar Mediterraneo (dove è comune anche nelle acque costiere italiane) e nell'Oceano Atlantico orientale (dal golfo di Guascogna all'Africa tropicale) e occidentale (dal Maine al Brasile).
È una specie pelagica che frequenta acque aperte e costiere.

Descrizione

Simile al tombarello da cui si distingue per le pinne dorsali contigue (nell'Auxis le due pinne sono separate da un largo spazio), per l'occhio proporzionalmente più piccolo ed il corpo meno slanciato, può essere confuso anche con il giovane tonno rosso che però non ha i caratteristici disegni sul dorso o con il tonnetto striato da cui è distinguibile per la diversa colorazione.
La livrea è azzurro scuro sul dorso e bianco madreperlaceo sul ventre. Nel terzo posteriore del corpo, in posizione dorsale ci sono disegni scuri molto simili a quelli del tombarello, inoltre ci sono 4-8 grossi punti neri sotto la pinna pettorale.
Raggiunge 1 m di lunghezza e massimo 15 kg di peso.

Alimentazione

Cattura pesci e cefalopodi pelagici.

Riproduzione

Si riproduce in primavera-estate.

Pesca

Abbocca facilmente alle lenze a traina ed è anche catturato con vari tipi di rete. Le carni sono ottime, simili a quelle del tonno. Misura minima di pesca è la lunghezza di almeno 30 cm. In base al regolamento CEE 1536/92 non può essere commercializzato come tonno, ma soltanto come palamita.

Note

Bibliografia

• Costa F., Atlante dei pesci dei mari italiani, Mursia, 1991, ISBN 88-425-1003-3
• Louisy P., Trainito E. (a cura di) Guida all'identificazione dei pesci marini d'Europa e del Mediterraneo. Milano, Il Castello, 2006, ISBN 88-8039-472-X

De Dwergtonijn (Euthynnus alletteratus) is een straalvinnige vis uit de familie van makrelen (Scombridae) en behoort derhalve tot de orde van baarsachtigen (Perciformes). De vis kan een lengte bereiken van 122 cm. De hoogst geregistreerde leeftijd is 10 jaar.

Leefomgeving

De Dwergtonijn komt in zeewater en brak water voor. De vis prefereert een tropisch klimaat en leeft hoofdzakelijk in de Atlantische Oceaan. Bovendien komt Euthynnus alletteratus voor in de Middellandse Zee. De diepteverspreiding is 1 tot 150 m onder het wateroppervlak.

Relatie tot de mens

De Dwergtonijn is voor de visserij van aanzienlijk commercieel belang. In de hengelsport wordt er weinig op de vis gejaagd.

Voor de mens is deze tonijn potentieel gevaarlijk, omdat er vermeldingen van ciguatera-vergiftiging zijn geweest.

Externe link

• Foto's van Euthynnus alletteratus op FishBase

• Froese, R., D. Pauly. en redactie. 2005. FishBase. Elektronische publicatie. www.fishbase.org, versie 06/2005.

1. ↑ (en) Dwergtonijn op de IUCN Red List of Threatened Species.

Tunnin er en fisk i makrellfamilien. Den er en svært sjelden gjest i norske farvann.

Artsnavnet er et diminutiv og betyr «liten tunfisk», noe som beskriver utseendet godt. På samme måte som makrellstørje har den et panser av store skjell på forkroppen, mens bakkroppen ikke har skjell. Bak på ryggen har den makrelllignende striper, og under brystfinnen og sidelinjen er det flere svarte flekker. Maksimal lengde er 100 cm og maksimal vekt 12 kg, men vanlig lengde er 30–80 cm.

Arten lever pelagisk i de øvre vannlagene i kystfarvann, og den er ikke vanlig ute på det åpne havet. Tunnin danner blandede stimer sammen med andre arter i makrellfamilien. Den er en opportunist som jakter på alle tilgjengelige byttedyr, som krepsdyr, mindre fisker, blekksprut, pelagiske snegler og kappedyr. Sildefisker er spesielt viktige. Tunninen er selv bytte for haier, gulfinnetun og seilfisker.

Tunnin er utbredt på begge sider av Atlanterhavet. I vest finnes den fra Nova Scotia i Canada sørover til sørlige Brasil. Den er vanlig i Mexicogolfen og Karibien. I øst er den utbredt fra De britiske øyer sørover til Sør-Afrika. Den finnes også i Middelhavet og Svartehavet.

Arten blir fisket kommersielt sammen med andre tunfisker og bonitoer. Den er også en populær sportsfisk i de varme delene av Atlanterhavet.

Litteratur

• P. Pethon (1998). Aschehougs store fiskebok (4 utg.). Aschehoug. s. 405. ISBN 82-03-22260-9.
• B.B. Collette og C.E. Nauen (1983). FAO species catalogue: Vol.2. Scombrids of the world: An annotated and illustrated catalogue of tunas, mackerels, bonitos and related species known to date. FAO Fish.Synop. s. 34–35. ISBN 92-5-101381-0.

Eksterne lenker

• (sv) Tunnin hos Dyntaxa
• (en) Tunnin – oversikt og omtale av artene i WORMS-databasen
• (en) Tunnin i Encyclopedia of Life
• (en) Tunnin i Global Biodiversity Information Facility
• (en) Tunnin hos Fossilworks
• (en) Tunnin hos NCBI
• (en) Tunnin hos ITIS
• (en) Tunnin hos FishBase
• (en) Kategori:Euthynnus alletteratus – bilder, video eller lyd på Wikimedia Commons
• (en) Euthynnus alletteratus – galleri av bilder, video eller lyd på Wikimedia Commons
• (en) Euthynnus alletteratus (Rafinesque, 1810) Little tunny - FishBase
• B. Collette m.fl. (2011). «Sarda sarda». IUCN 2011. IUCN Red List of Threatened Species. Version 2011.2. Besøkt 18. juni 2012.

Euthynnus alletteratus é uma espécie de peixes da família Scombridae da ordem dos Perciformes.

Descrição

Os machos podem alcançar os 122 cm de comprimento total e os 16,5 kg de peso.^[1]

A espécie tem distribuição natural nas águas tropicais e subtropicais de todos os oceanos, estando presente no Mar Mediterrâneo, no Mar Negro, no Mar do Caribe e no Golfo do México

Notas

Bibliografia

• Fenner, Robert M.: The Conscientious Marine Aquarist. Neptune City, New Jersey, Estados Unidos : T.F.H. Publications, 2001.
• Helfman, G., B. Collette y D. Facey: The diversity of fishes. Blackwell Science, Malden, Massachusetts, Estados Unidos , 1997.
• Hoese, D.F. 1986: . A M.M. Smith y P.C. Heemstra (eds.) Smiths' sea fishes. Springer-Verlag, Berlim, Alemanha.
• Maugé, L.A. 1986. A J. Daget, J.-P. Gosse y D.F.E. Thys van den Audenaerde (eds.) Check-list of the freshwater fishes of Africa (CLOFFA). ISNB Bruxelas; MRAC, Tervuren, Flandres; e ORSTOM, Paris, França. Vol. 2.
• Moyle, P. y J. Cech.: Fishes: An Introduction to Ichthyology, 4a. edición, Upper Saddle River, New Jersey, Estados Unidos: Prentice-Hall. Ano 2000.
• Nelson, J.: Fishes of the World, 3a. edición. New York, Estados Unidos: John Wiley and Sons. Año 1994.
• Wheeler, A.: The World Encyclopedia of Fishes, 2.ª edição, Londres: Macdonald. Ano 1985.

Tunnina (Euthynnus alletteratus) är en pelagisk stimfisk i familjen makrillfiskar som finns i Atlanten och påminner om en liten tonfisk.

Utseende

Tunninan påminner om en liten tonfisk. Framkroppen och ryggen är blåaktiga, medan de undre sidorna och buken är vitaktiga. Bakre delen av ryggen har oregelbundna tvärstreck.^[2] På framkroppens nedre del har den 3 till 7 mörka fläckar med vit kontur. Den främre ryggfenan är lång och sitter nära den bakre. Stjärtroten har 7 till 8 småfenor.^[3] Arten har endast fjäll på framkroppen och längs sidolinjen.^[4] Arten blir vanligtvis upp till 80 cm lång, även om längdrekordet är 122 cm och maxvikten 16,5 kg.^[5]

Vanor

Arten är en pelagisk stimfisk som håller sig nära kusterna^[3] från ytan ner till 150 meters djup. Den lever på fiskar, framför allt sillfiskar, kräftdjur, manteldjur och bläckfiskar. Arten kan bli upp till 10 år gammal.^[4]

Den tjänar som byte åt många andra fiskar, som andra, större tonfiskar, svärdfisk och många hajar. Mindre tunninor kan även tas av havsfågel.^[4]

Fortplantning

Honan blir könsmogan vid en längd mellan 27 och 37 cm, medan hanens könsmognad inträffar vid omkring 40 cm längd. I Atlanten leker tunninan från april till november, medan lektiden varar från vår till sensommar i Medelhavet. Leken sker på djupare vatten, i Atlanten utanför kontinentalhyllan, där honan kan lägga upp till 1 750 000 små (0,8 – 1 mm), pelagiska ägg. Dessa kläcks redan ett dygn senare.^[4]

Utbredning

Tunninan finns nära kusterna i Atlantens varmare regioner. På västra sidan uppträder den från Massachusetts i USA via Karibien till Brasilien.^[4] På östra sidan sträcker sig utbredningsområdet från Brittiska öarna till Sydafrika^[3] inklusive Medelhavet^[5]. I Skandinavien har arten påträffats i Norge, Sverige och Danmark.^[2]

Kommersiell användning

Arten fiskas, både för mänsklig konsumtion, som industrifisk^[3] och som betesfisk. Den är också föremål för sportfiske.^[4]

Referenser

1. ^ ”Euthynnus alletteratus (Rafinesque, 1810)” (på engelska). ITIS. http://www.itis.gov/servlet/SingleRpt/SingleRpt?search_topic=TSN&search_value=172402. Läst 3 september 2010.
2. ^ [a b] Curry-Lindahl, Kai (1985). Våra fiskar : havs- och sötvattensfiskar i Norden och övriga Europa. Stockholm: Norstedts. sid. 481. ISBN 91-1-844202-1
3. ^ [a b c d] Muus, Bent J; Nielsen, Jørgen G; Svedberg, Ulf (1999). Havsfisk och fiske i Nordvästeuropa. Stockholm: Prisma. sid. 241. ISBN 91-518-3505-3
4. ^ [a b c d e f] Cathleen Bester. ”LITTLE TUNNY” (på engelska). Florida Museum of Natural History. http://www.flmnh.ufl.edu/fish/gallery/descript/littletunny/littletunny.html. Läst 3 september 2010.
5. ^ [a b] Luna, Susan M. (20 april 2010). ”Euthynnus alletteratus (Rafinesque, 1810) Little tunny” (på engelska). Fishbase. http://www.fishbase.org/summary/speciessummary.php?id=97. Läst 3 september 2010.

Тунець малий (Euthynnus alletteratus) — є найбільш поширеним видом тунця в Атлантичному океані. Проживає в помірних і тропічних водах Атлантики, Середземного моря та на півдні Чорного моря. Живиться зазвичай пелагічними рибами. Використовується як приманка для акул і марліну у зв'язку з тим, що добре тримається на гачку. Малий тунець, на думку багатьох, є смітною рибою через невелику поживну цінність.

Будова

Малий тунець в порівнянні з іншими видами тунця невеликий. Середня довжина у дорослого тунця становить 64 см. Деякі особини можуть досягати довжини 100 см. Найбільший виловлений був довжиною 120 см і важив 17 кг.

Джерела

• Froese R., Pauly D. (eds.) (2013). "Euthynnus alletteratus" на FishBase. Версія за вересень 2013 року.

Череп пятнистого тунца

Размножение и жизненный цикл

Размножаются икрометанием. Нерест начинается, когда вода прогревается минимум до 25 °C. В Атлантике сезон размножения длится с апреля по ноябрь, в Средиземном море с мая по сентябрь, пик интенсивности приходится на июль-август. Тунцы мечут икру порциями вдали от берега на глубине 30—40 м^[11]. Плодовитость варьируется от 70 тыс. до 2,2 млн икринок за нерестовый сезон^[9]. Оплодотворение происходит в толще воды. Икра пелагическая, прозрачная, сферической формы обладает положительной плавучестью, которую обеспечивает жировая капля. Диаметр икринок 0,8—1,1 мм, цвет светло-янтарный. Примерно через 24 часа после оплодотворения вылупляются личинки длиной около 3 мм. Спустя 48 часов глаза обретают пигментацию. При достижении длины 3,7—14 мм развиваются зубы, голова укрупняется, рыло вытягивается и появляются плавники. Личинки длиной 14—174 мм становятся похожи на взрослых рыб с удлинённым веретенообразным телом^[11][12]. Половая зрелость наступает в возрасте 3 лет при достижении длины около 38 см^[12]. Среди молоди соотношение полов равно, а среди взрослых рыб преобладают самцы^[9]. Продолжительность жизни оценивается в 8—10 лет. Длительность поколения около 4 лет^[1].

Взаимодействие с человеком

Является объектом коммерческого промысла. В промышленных масштабах 99 % пятнистых тунцов промышляют с помощью кошельковых неводов. Эти рыбы служат сырьём для производства консервов, также мясо поступает на рынок в свежем, солёном, замороженном и копчёном виде^[6]. У них более тёмное по сравнению с прочими тунцами мясо, обладающее сильно выраженным вкусом. Есть данные о заболевании сигуатерой при его употреблении^[11]. Международный союз охраны природы оценил охранный статус вида как «Вызывающий наименьшие опасения»^[1]. Малые тунцы, к которым относится пятнистый тунец, включены в список далеко мигрирующих видов Конвенции ООН по морскому праву^[3].

Примечания

小鮪為輻鰭魚綱鱸形目鯖亞目鯖科的其中一種，分布於大西洋熱帶及亞熱帶海域，棲息深度1-150公尺，體長可達122公分，棲息在沿岸表層水域，成群活動，屬肉食性，以魚類、甲殼類等為食，可做為食用魚、遊釣魚，有雪卡魚中毒的報告。

参考文献

• Froese, Rainer & Daniel Pauly, eds. (2012). Euthynnus alletteratus in FishBase. 2012年7月版本

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