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True tunas Temporal range: Tertiary–holocene PreꞒ Ꞓ O S D C P T J K Pg N
Yellowfin tuna
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Class:	Actinopterygii
Order:	Scombriformes
Family:	Scombridae
Tribe:	Thunnini
Genus:	Thunnus South, 1845
Type species
Scomber thynnus Linnaeus, 1758
Subgenus
T. (Thunnus) (bluefin group) T. (Neothunnus) (yellowfin group)
Synonyms
Albacora Jordan, 1888 Germo Jordan, 1888 Thynnus Aguilera, 2020 Kishinoella Jordan & Hubbs, 1925 Neothunnus Kishinouye, 1923 Orcynus Cuvier, 1816 Parathunnus Kishinouye, 1923 Semathunnus Fowler, 1933

Thunnus is a genus of ocean-dwelling, ray-finned bony fish from the mackerel family, Scombridae. More specifically, Thunnus is one of five genera which make up the tribe Thunnini – a tribe that is collectively known as the tunas. Also called the true tunas or real tunas, Thunnus consists of eight species of tuna (more than half of the overall tribe), divided into two subgenera.

Their coloring, metallic blue on top and shimmering silver-white on the bottom, helps camouflage them from above and below. Atlantic bluefin tuna, the largest member of this genus, can grow to 15 feet (4.6 m) long and weigh up to 1,500 pounds (680 kg). All tunas are extremely strong, muscular swimmers, and the yellowfin tuna is known to reach speeds of up to 50 miles per hour (80 km/h) when pursuing prey. As with all tunas, members of this genus are warm-blooded, which is a rare trait among fish; this enables them to tolerate cold waters and to dive to deeper depths. Bluefin tunas, for example, are found in Newfoundland and Iceland, and also in the tropical waters of the Gulf of Mexico and the Mediterranean Sea, where some individuals go each year to spawn.

Due to overfishing, the range of this genus has declined significantly, having been effectively extirpated from the Black Sea, for example.

Taxonomy

The word Thunnus is the Middle Latin form of the Greek thýnnos (θύννος, "tuna, tunny") – which is in turn derived from thynō (θύνω, "to rush; to dart"). The first written use of the word was by Homer.

Based on morphology and short-length mitochondrial DNA sequence data, the genus Thunnus is currently classified into two subgenera: Thunnus (Thunnus) (the bluefin group), and Thunnus (Neothunnus) (the yellowfin group). However this classification has been questioned by a recent phylogenetic analysis of nuclear DNA sequence data, which resolved different relationships among species and did not support the traditional definition of the bluefin and yellowfin groups. Specifically, these analyses substantiated the division of Pacific and Atlantic Tuna in two separate species and suggested that Bigeye Tuna were actually a member of subgenus Neothunnus, not subgenus Thunnus. Earlier nuclear ribosomal DNA phylogenetic reconstructions also showed similar results.

This genus has eight species in two subgenera:

• Subgenus Thunnus (Thunnus):
  • Albacore, T. alalunga (Bonnaterre, 1788)
  • Southern bluefin tuna, T. maccoyii (Castelnau, 1872)
  • Bigeye tuna, T. obesus (Lowe, 1839)
  • Pacific bluefin tuna, T. orientalis (Temminck & Schlegel, 1844)
  • Atlantic bluefin tuna, T. thynnus (Linnaeus, 1758)
• Subgenus Thunnus (Neothunnus):
  • Yellowfin tuna, T. albacares (Bonnaterre, 1788)
  • Blackfin tuna, T. atlanticus (Lesson, 1831)
  • Longtail tuna, T. tonggol (Bleeker, 1851)

Species

Until recently, seven Thunnus species were thought to exist, and Atlantic bluefin tuna and Pacific bluefin tuna were subspecies of a single species. In 1999, Collette established that based on both molecular and morphological considerations, they are, in fact, distinct species.

Thunnus, the true tunas
Image	Common name	Scientific name	Maximum length	Common length	Maximum weight	Maximum age	Trophic level	Source	IUCN status
Thunnus (Thunnus) – the bluefin group
	Albacore tuna	T. alalunga (Bonnaterre, 1788)	1.4 m (4.6 ft)	1.0 m (3.3 ft)	60.3 kg (133 lb)	9–13 yrs	4.31		Least Concern
	Southern bluefin tuna	T. maccoyii (Castelnau, 1872)	2.45 m (8.0 ft)	1.6 m (5.2 ft)	260 kg (570 lb)	20–40 yrs	3.93		Endangered
	Bigeye tuna	T. obesus (Lowe, 1839)	2.5 m (8.2 ft)	1.8 m (5.9 ft)	210 kg (460 lb)	5–16 yrs	4.49		Vulnerable
	Pacific bluefin tuna	T. orientalis (Temminck & Schlegel, 1844)	3.0 m (9.8 ft)	2.0 m (6.6 ft)	450 kg (990 lb)	15–26 yrs	4.21		Near Threatened
	Atlantic bluefin tuna	T. thynnus (Linnaeus, 1758)	4.6 m (15 ft)	2.0 m (6.6 ft)	684 kg (1,508 lb)	35–50 yrs	4.43		Least Concern
Thunnus (Neothunnus) – the yellowfin group
	Blackfin tuna	T. atlanticus (Lesson, 1831)	1.1 m (3.6 ft)	0.7 m (2.3 ft)	22.4 kg (49 lb)		4.13		Least concern
	Longtail tuna, northern bluefin tuna, tongol tuna	T. tonggol (Bleeker, 1851)	1.45 m (4.8 ft)	0.7 m (2.3 ft)	35.9 kg (79 lb)	18 years	4.50		Data deficient
	Yellowfin tuna	T. albacares (Bonnaterre, 1788)	2.4 m (7.9 ft)	1.5 m (4.9 ft)	200 kg (440 lb)	5–9 yrs	4.34		Least Concern

Overfishing

The worldwide demand for sushi and sashimi, coupled with increasing population growth, has resulted in global stocks of the species being overfished and bluefin is the most endangered and considered "a serious conservation concern". Complicating the efforts for sustainable management of bluefin fish stocks within national exclusive economic zones (EEZ) is bluefin migrate long distances and hunt in the midocean that is not part of any country's EEZ, so have been vulnerable to overfishing by multiple countries' fishing fleets. International agreements and conventions are good-faith agreements and are difficult to monitor or enforce. Though this fish has been farmed in captivity by the Japanese and by the Australians with the help of the Japanese, yields are lower than other farmed fish due to the slow growth rate of bluefin tuna, therefore keeping prices high. On December 30, 2012, a 222-kilogram (489 lb) bluefin tuna caught off northeastern Japan, was sold at the Tsukiji fish market in Tokyo for a record 155.4 million yen ($1.76 million) – a unit price of JP¥ 1.274 million/kg (US$3,600/lb).

References

1. ^ Graham, Jeffrey B.; Dickson, Kathryn A. (2004). "Tuna Comparative Physiology". The Journal of Experimental Biology. 207 (23): 4015–4024. doi:10.1242/jeb.01267. PMID 15498947.
2. Sepkoski, Jack (2002). "A compendium of fossil marine animal genera". Bulletins of American Paleontology. 364: 560. Archived from the original on 2011-07-23. Retrieved 2008-01-08.
3. Bernal, Diego; Brill, Richard W.; Dickson, Kathryn A.; Shiels, Holly A. (2017-12-01). "Sharing the water column: physiological mechanisms underlying species-specific habitat use in tunas". Reviews in Fish Biology and Fisheries. 27 (4): 843–880. doi:10.1007/s11160-017-9497-7. ISSN 1573-5184. S2CID 20554689. Archived from the original on 2020-06-17. Retrieved 2019-12-01.
4. Hogan, C. Michael, Overfishing. Encyclopedia of Earth. eds. Sidney Draggan and Cutler Cleveland. National council for Science and the Environment, Washington DC
5. θύννος in Liddell, Henry George; Scott, Robert (1940) A Greek–English Lexicon, revised and augmented throughout by Jones, Sir Henry Stuart, with the assistance of McKenzie, Roderick. Oxford: Clarendon Press. In the Perseus Digital Library, Tufts University.
6. θύνω in Liddell and Scott.
7. Alvarado Bremer, J.R.; Naseri, I.; Ely, B. (2016). "ROrthodox and unorthodox phylogenetic relationships among tunas revealed by the nucleotide sequence analysis of the mitochondrial DNA control region". Journal of Fish Biology. 50 (3): 540–554. doi:10.1111/j.1095-8649.1997.tb01948.x.
8. ^ Díaz-Arce, Natalia; Arrizabalaga, Haritz; Murua, Hilario; Irigoien, Xabier; Rodríguez-Ezpelata, Naiara (2016). "RAD-seq derived genome-wide nuclear markers resolve the phylogeny of tunas". Molecular Phylogenetics and Evolution. 102: 202–207. doi:10.1016/j.ympev.2016.06.002. hdl:10754/612968. PMID 27286653.
9. Ciezarek, Adam G.; Osborne, Owen G.; Shipley, Oliver N.; Brooks, Edward J.; Tracey, Sean R.; McAllister, Jaime D.; Gardner, Luke D.; Sternberg, Michael J. E.; Block, Barbara; Savolainen, Vincent (2019-01-01). "Phylotranscriptomic Insights into the Diversification of Endothermic Thunnus Tunas". Molecular Biology and Evolution. 36 (1): 84–96. doi:10.1093/molbev/msy198. ISSN 0737-4038. PMC 6340463. PMID 30364966.
10. Chow, S.; Nakagawa, T.; Suzuki, N.; Takeyama, H.; Matsunaga, T. (2006). "Phylogenetic relationships among Thunnus species inferred from rDNA ITS1 sequence". Journal of Fish Biology. 68 (A): 24–35. doi:10.1111/j.0022-1112.2006.00945.x.
11. Collette, B.B. (1999). "Mackerels, molecules, and morphology". In Séret, B.; Sire, J.Y. (eds.). Proceedings. 5th Indo-Pacific Fish Conference: Nouméa, New Caledonia, 3–8 November 1997. Paris: Société Française d'Ichtyologie pp. 149–164. ISBN 978-2-9507330-5-4. Archived from the original on 2023-11-30. Retrieved 2017-09-16.
12. Tanaka, Y.; Satoh, K.; Iwahashi, M.; Yamada, H. (2006). "Growth-dependent recruitment of Pacific bluefin tuna Thunnus orientalis in the northwestern Pacific Ocean". Marine Ecology Progress Series. 319: 225–235. Bibcode:2006MEPS..319..225T. doi:10.3354/meps319225.
13. Froese, Rainer; Pauly, Daniel (eds.). "Thunnus alalunga". FishBase. January 2012 version.
14. ^ Collette, B.; et al. (2021). "Thunnus alalunga". IUCN Red List of Threatened Species. 2021. Retrieved 29 March 2022.
15. Froese, Rainer; Pauly, Daniel (eds.). "Thunnus maccoyii". FishBase. January 2012 version.
16. ^ Collette, B.; et al. (2021). "Thunnus maccoyii". IUCN Red List of Threatened Species. 2021. Retrieved 29 March 2022.
17. Froese, Rainer; Pauly, Daniel (eds.). "Thunnus obesus". FishBase. January 2012 version.
18. ^ Collette, B.; et al. (2021). "Thunnus obesus". IUCN Red List of Threatened Species. 2021. Retrieved 29 March 2022.
19. Froese, Rainer; Pauly, Daniel (eds.). "Thunnus orientalis". FishBase. January 2012 version.
20. ^ Collette, B.; et al. (2021). "Thunnus orientalis". IUCN Red List of Threatened Species. 2021. Retrieved 29 March 2022.
21. Froese, Rainer; Pauly, Daniel (eds.). "Thunnus thynnus". FishBase. January 2012 version.
22. ^ Collette, B.; et al. (2021). "Thunnus thynnus". IUCN Red List of Threatened Species. 2021. Retrieved 9 January 2015.
23. Froese, Rainer; Pauly, Daniel (eds.). "Thunnus atlanticus". FishBase. January 2012 version.
24. Collette, B.; et al. (2010). "Thunnus atlanticus". IUCN Red List of Threatened Species. 2010. Retrieved 29 March 2022.{{cite iucn}}: old-form url (help)
25. Froese, Rainer; Pauly, Daniel (eds.). "Thunnus tonggol". FishBase. January 2012 version.
26. ^ Collette, B.; et al. (2009). "Thunnus tonggol". IUCN Red List of Threatened Species. 2009. Retrieved 29 March 2022.{{cite iucn}}: old-form url (help)
27. Froese, Rainer; Pauly, Daniel (eds.). "Thunnus albacares". FishBase. January 2012 version.
28. ^ Collette, B.; et al. (2021). "Thunnus albacares". IUCN Red List of Threatened Species. 2021. Retrieved 29 March 2022.{{cite iucn}}: old-form url (help)
29. George Karleskint; Richard Turner; James Small (2009). Introduction to Marine Biology. Cengage Learning. p. 522. ISBN 978-0-495-56197-2.
30. "Tuna, Bluefin". Archived from the original on 2011-07-22.
31. ^ "Managed to death". The Economist. 2008-10-30. Archived from the original on 2011-02-11. Retrieved 2011-01-08.
32. Thunnus orientalis#Farming
33. "A bluefin tuna sells for record $1.76M in Tokyo". USA Today. 4 January 2013. Archived from the original on 28 July 2018. Retrieved 5 January 2013.

Further reading

• Charles Clover. 2004. The End of the Line: How Overfishing Is Changing the World and What We Eat. Ebury Press, London. ISBN 0-09-189780-7
• Newlands, Nathaniel K.; Molly E. Lutcavage; Tony J. Pitcher (2006). "Atlantic Bluefin Tuna in the Gulf of Maine, I: Estimation of Seasonal Abundance Accounting for Movement, School and School-Aggregation Behaviour". Environmental Biology of Fishes. 77 (2): 177–195. doi:10.1007/s10641-006-9069-5. ISSN 0378-1909. S2CID 12596873.

External links

• Froese, Rainer; Pauly, Daniel (eds.). "Species in genus Thunnus". FishBase. January 2006 version.
• Nutritional benefits of tuna Archived 2016-01-19 at the Wayback Machine
• The International Commission for the Conservation of Atlantic Tunas

v t e Tuna
True tuna	Tuna Thunnus Albacore Bigeye tuna Atlantic bluefin tuna Blackfin tuna Longtail tuna Southern bluefin tuna Pacific bluefin tuna Yellowfin tuna
Other tuna	Scombridae Black skipjack tuna Bullet tuna Dogtooth tuna Frigate tuna Mackerel tuna Leaping bonito Little tunny Skipjack tuna Slender tuna Auxis
Fishing and fisheries	Almadraba US bluefin tuna industry
As food	Botargo Cakalang fufu Chūtoro Katsuobushi Kezuriki Mojama Tekkadon Tuna casserole Tuna fish sandwich Tuna pot Tuna salad
Other	Dolphin friendly tuna Scombroid food poisoning Tuna Fishing (painting) Tunagate
Organisations	IATTC IOTC ICCAT CCSBT WCPFC International Seafood Sustainability Foundation#Practices Nauru Agreement Regional Fisheries Management Organisation
Related articles	List of tuna dishes

• Thunnus
• Marine fish genera
• Extant Cenozoic first appearances