The threadfin jack or thread pompano, Carangoides otrynter, is a species of coastal marine fish in the jack family Carangidae. The species inhabits the tropical waters of the eastern Pacific Ocean from Baja California in the north to Ecuador and the Galapagos Islands in the south. It is a moderately large fish, growing to 60 cm (24 in) and may be recognized by its filamentous dorsal and anal fin lobes. The threadfin jack inhabits both deeper coastal waters and inshore environments, including reefs and estuaries, where it preys on minute benthic and pelagic organisms, including small fishes and crustaceans. Very little is known about the ecology and reproductive cycle in the species. The threadfin jack is of importance to fisheries throughout its distribution, caught by hook-and-line and ne