This was the first naming pertaining to the fish, and would normally have priority over any names assigned later. Georges Cuvier resurrected this name when he described the species as Caranx ascensionis in 1833. The taxonomic history of the black jack is quite complex, with the species first referred to in error as Scomber adscensionis ( Osbeck, 1771), which was also used to describe what is now known as Pseudocaranx dentex. Caranx itself is part of the larger jack and horse mackerel family Carangidae, which in turn is part of the order Carangiformes. The black jack is classified within the genus Caranx, one of a number of groups known as the jacks or trevallies. The species was initially named Caranx ascensionis by Georges Cuvier, however several issues with the use of this name have seen Felipe Poey's name Caranx lugubris become the valid scientific name. The species has a reputation as a gamefish, and is variably considered a terrible or excellent food fish, although several cases of ciguatera poisoning have been attributed to the species. Black jack are of high importance to many island fisheries, but are rarely encountered in most continental fisheries. The early life history of the species is very poorly understood. Sexual maturity is reached at 34.6 cm in females and 38.2 cm in males, with spawning taking place between February and September in the Caribbean. It is a predatory fish, taking a variety of fish, crustaceans and molluscs as prey. The black jack lives either individually or in small schools, and is known to school with other species. The largest recorded length is 1 m and weight of 17.9 kg. The species is easily distinguished by its black to grey fins and jet black scutes, with the head having a steep profile near the snout.

Black jack are rare in shallow waters, preferring deep reefs, ledges and seamounts in clear waters. The species is particularly prevalent around offshore islands such as the Caribbean islands in the Atlantic, Hawaii and French Polynesia in the Pacific and the Seychelles and Maldives in the Indian Ocean. The species has a circumtropical distribution, found in oceanic, offshore waters of the tropical zones of the Pacific, Atlantic and Indian Oceans. Caranx tenebrosus ( Jordan, Evermann & Wakiya, 1927)Ĭaranx lugubris, the black jack, black trevally, black kingfish, coal fish or black ulua, is a species of large ocean fish in the jack family Carangidae.

Bio of jack blackjack