The little tunny (Euthynnus alletteratus) is the most common tuna in the Atlantic Ocean. It is found in warm temperate and tropical waters of the Atlantic and the Mediterranean; in the western Atlantic, it ranges from Brazil to the New England states.
As nouns the difference between tuna and mackerel is that tuna is any of several species of fish, of the genus thunnus , in the family scombridae or tuna can be the prickly pear, a type of cactus native to mexico in the genus opuntia while mackerel is an edible fish of the family scombridae, often speckled or mackerel can be (obsolete) a pimp; also, a bawd.
Skipjack tuna is used extensively in Japanese cuisine, where it is known as katsuo (鰹/かつお). Besides being eaten seared (katsuo tataki (鰹のタタキ)) and raw in sushi and sashimi, it is also smoked and dried to make katsuobushi, the central ingredient in dashi (a common Japanese fish stock).
In recent years, opening day fish auctions at Tokyo's Tsukiji fish market have seen record-setting prices for bluefin tuna, reflecting market demand. In each of 2010, 2011, 2012 and 2013, new record prices have been set for a single fish – the current record is 155.4 million japanese yen (US$1.76 million) for a 221 kg (487 lb) bluefin, or a unit price of JP¥ 703,167/kg (US$3,603/lb).