Japanese horse mackerel

The Japanese horse mackerel (Trachurus japonicus) is a species named after mackerel in the family Carangidae.[1] Their maximum reported length is 50 cm (20 in) with a common length of 35 cm (14 in). They have a maximum reported weight of 0.66 kg (1.5 lb) and a maximum reported age of 12 years.[2] They are found around the coast of Japan, apart from Okinawa Island, usually on sandy bottoms of 50–275 m (164–902 ft) deep.[2] They feed mainly on small crustaceans such as copepods, and shrimps and small fish. They are similar to the yellowtail horse mackerel around New Zealand and Australia, apart from having more gill rakers and larger eyes.[3]

The Japanese name for the horse mackerel is aji (あじ), and by default generally implies the species Trachurus japonicus(which can be more specifically referred to as ma-aji (まあじ), literally "true aji"). The name is most commonly written in hiragana; although a kanji (鯵) does exist, it is not in common use. It is commonly deep fried ("aji furai" あじフライ) or salt-grilled ("shioyaki aji" 塩焼きあじ).

In Korean cuisine, the fish is dubbed jeon-gaeng-i (전갱이) and is the default horse mackerel designated by this name. It is commonly grilled or fried as a jeon-gaeng-i gui (전갱이 구이). Among the specialties of Jeju cuisine is the soup gagjaegi-gug(각재기국), the name of which is derived from the name for the fish in the Jeju language.