''Euthynnus affinis'', the mackerel tuna, little tuna, eastern little tuna, wavyback skipjack tuna, kawakawa, or tongkol komo is a

species A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...

of ray-finned

bony fish Osteichthyes ( ; ), also known as osteichthyans or commonly referred to as the bony fish, is a Biodiversity, diverse clade of vertebrate animals that have endoskeletons primarily composed of bone tissue. They can be contrasted with the Chondricht ...

in the

family Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). It forms the basis for social order. Ideally, families offer predictabili ...

Scombridae The mackerel, tuna, and bonito family, Scombridae, includes many of the most important and familiar food fishes. The family consists of 51 species in 15 genera and two subfamilies. All species are in the subfamily Scombrinae, except the but ...

, or

mackerel Mackerel is a common name applied to a number of different species of pelagic fish, mostly from the family Scombridae. They are found in both temperate and tropical seas, mostly living along the coast or offshore in the oceanic environment. ...

family. It belongs to the

tribe The term tribe is used in many different contexts to refer to a category of human social group. The predominant worldwide use of the term in English is in the discipline of anthropology. The definition is contested, in part due to conflict ...

Thunnini, better known as the

tuna A tuna (: tunas or tuna) is a saltwater fish that belongs to the tribe Thunnini, a subgrouping of the Scombridae ( mackerel) family. The Thunnini comprise 15 species across five genera, the sizes of which vary greatly, ranging from the bul ...

s. It is also in the genus Euthynnus of "little tunas," which includes the little tunny and the black skipjack. ''Euthynnus affinis'' formerly was known as ''Euthynnus yaito''.

Description

''E. Affinis'' displays a typical tuna body shape with a slender, elongated body, and a deeply forked tail. It has a small amount of scales and 2 or more dark spots between the pelvic and pectoral fins. The first dorsal fin has 10-15 spines and is around 1/3rd of the tuna's body height. On its back, it displays 12 oblique stripes and a dark blue coloration for

countershading Countershading, or Thayer's law, is a method of camouflage in which animal coloration, an animal's coloration is darker on the top or upper side and lighter on the underside of the body. This pattern is found in many species of mammals, reptile ...

. It can reach a maximum length of and a weight up to . To distinguish from the closely related black skipjack, also of the Pacific Ocean, the kawakawa has more broken stripes instead of straight stripes spanning the side of the body on the black skipjack. The stripes on the back of the kawakawa are more orderly than those of the little tunny, which is primary found in the Atlantic Ocean.

Distribution and ecology

''E. Affinis'' is an

Indo-Pacific The Indo-Pacific is a vast biogeographic region of Earth. In a narrow sense, sometimes known as the Indo-West Pacific or Indo-Pacific Asia, it comprises the tropical waters of the Indian Ocean, the western and central Pacific Ocean, and the ...

species which is found from the

Red Sea The Red Sea is a sea inlet of the Indian Ocean, lying between Africa and Asia. Its connection to the ocean is in the south, through the Bab-el-Mandeb Strait and the Gulf of Aden. To its north lie the Sinai Peninsula, the Gulf of Aqaba, and th ...

French Polynesia French Polynesia ( ; ; ) is an overseas collectivity of France and its sole #Governance, overseas country. It comprises 121 geographically dispersed islands and atolls stretching over more than in the Pacific Ocean, South Pacific Ocean. The t ...

, but can also be found near

Baja California Baja California, officially the Free and Sovereign State of Baja California, is a state in Mexico. It is the northwesternmost of the 32 federal entities of Mexico. Before becoming a state in 1952, the area was known as the North Territory of B ...

. The kawakawa is a

pelagic The pelagic zone consists of the water column of the open ocean and can be further divided into regions by depth. The word ''pelagic'' is derived . The pelagic zone can be thought of as an imaginary cylinder or water column between the sur ...

, highly migratory species, often schooling from the surface of the water to depths of . However, it often sticks close to coastal structures and neritic shelves instead of the open ocean. It is also known to commonly inhabit coastal reefs and move into estuaries. It prefers waters ranging from . It is a highly opportunistic feeder, eating

squid A squid (: squid) is a mollusc with an elongated soft body, large eyes, eight cephalopod limb, arms, and two tentacles in the orders Myopsida, Oegopsida, and Bathyteuthida (though many other molluscs within the broader Neocoleoidea are also ...

fish A fish (: fish or fishes) is an aquatic animal, aquatic, Anamniotes, anamniotic, gill-bearing vertebrate animal with swimming fish fin, fins and craniate, a hard skull, but lacking limb (anatomy), limbs with digit (anatomy), digits. Fish can ...

crustacean Crustaceans (from Latin meaning: "those with shells" or "crusted ones") are invertebrate animals that constitute one group of arthropods that are traditionally a part of the subphylum Crustacea (), a large, diverse group of mainly aquatic arthrop ...

s, and

zooplankton Zooplankton are the heterotrophic component of the planktonic community (the " zoo-" prefix comes from ), having to consume other organisms to thrive. Plankton are aquatic organisms that are unable to swim effectively against currents. Consequent ...

. Like other tuna species, it will often form large, multi-species schools with other

scombridae The mackerel, tuna, and bonito family, Scombridae, includes many of the most important and familiar food fishes. The family consists of 51 species in 15 genera and two subfamilies. All species are in the subfamily Scombrinae, except the but ...

s like the

yellowfin tuna The yellowfin tuna (''Thunnus albacares'') is a species of tuna found in pelagic waters of tropical and subtropical oceans worldwide. Yellowfin is often marketed as ahi, from the Hawaiian , a name also used there for the closely related bigeye ...

and frigate mackerel. Predators of ''E. Affinis'' include larger tuna, billfish, sharks, birds, and marine mammals. Euthynnus affinis Red Sea

Fisheries

While often being seen as an undesirable fish like others in its genus due to its strong taste and dark red meat, it is commonly eaten in Hawaiian and Oceanic cultures, as well as being used in

sashimi is a Japanese cuisine, Japanese delicacy consisting of fresh raw fish or Raw meat, meat sliced into thin pieces and often eaten with soy sauce. Origin The word ''sashimi'' means 'pierced body', i.e., "wikt:刺身, 刺身" = ''sashimi'', whe ...

. The kawakawa is also caught in large amounts in the indo-pacific region, and is canned and sold frozen for human consumption. It is also commonly used for pet food. Due to it being a reef-frequenting species, there is a possibility of

ciguatera poisoning Ciguatera fish poisoning (CFP), also known as ciguatera, is a foodborne illness caused by eating tropical reef fish contaminated with ciguatoxins. Such individual fish are said to be ciguatoxic. Symptoms may include diarrhea, vomiting, numbness, ...

References

External links

{{Taxonbar, from=Q9125703 affinis Fish of Hawaii Fish described in 1849 Taxa named by Theodore Edward Cantor