The black jack, Caranx lugubris (also known as the black trevally, black kingfish, coal fish and black ulua), is a species of large ocean fish in the jack family Carangidae. The species has a circumtropical distribution, found in oceanic, offshore waters of the tropical zones of the Pacific, Atlantic and Indian Oceans. 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. Black jack are rare in shallow waters, preferring deep reefs, ledges and seamounts in clear waters. 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. The largest recorded length is 1 m an