The longnose trevally, Carangoides chrysophrys (also known as the club-nosed trevally, grunting trevally, and dusky trevally), is a species of inshore marine fish in the jack family, Carangidae. The species is distributed throughout the tropical and subtropical waters of the Indian and west Pacific Oceans from South Africa to New Zealand and Japan, inhabiting coastal waters, especially reefs, to a depth of 90 m. The longnose trevally is distinguished from similar species by a combination of a scaleless breast and the number of gill rakers and fin rays. It is a moderately large fish, growing to a maximum known length of 72 cm and 4.35 kg. The longnose trevally is a predatory fish, consuming small fish, crustaceans and molluscs. The species is of minor commercial importance throughout its range, and is considered to be a good table fish.
The species was first scientifically described by the French taxonomist Georges Cuvier in 1833, based on the holotype specimen collected from the waters of the Seychelles. He named the new species Caranx chrysophrys, with the specific name meaning 'golden eyebrow' in Greek. The generic position of the species was revised twice, being placed in Citula by William Ogilby and finally into Carangoides by Ian Munro, where it has remained. The species has been independently described on a number of occasions, the first when Pieter Bleeker identified a fish he believed was similar, but not the same as Carangoides chrysophrys, and named it Carangoides chrysophryoides. Other synonyms include Caranx nigrescens, Caranx jayakari and Caranx typus. These are all considered to be junior synonyms under the ICZN rules and are no longer used. The species has a number of common names, with the most often used names, 'longnose trevally' (or 'longnose kingfish') and 'club-nosed trevally' in reference to the snout profile of the fish. The names 'dusky trevally' and 'grunting trevally' are used for the fish in the United States.
The longnose trevally is generally silver in colour, with the body and head greenish blue above, becoming silvery with yellow-green reflections below. The operculum has a small black blotch on the upper margin. The dorsal and anal fins range in colour from whitish to pale yellow to dusky, with the membranes of soft anal fin rays often having a white spot at the base. The caudal and pectoral fins are pale to dusky yellow. There are records of large adults exhibiting very dark head and fin colouration, nearing black. It has been suggested these fish are perhaps exhibiting mating or spawning colouration.
The longnose trevally is an inshore fish, normally found on coastal reefs and occasionally in large protected bays. It appears to be more tolerant of dirty, turbid waters than most of it relatives, but is not seen in estuaries. Juveniles reportedly inhabit shallow bays close to the coast, and are occasionally seen near beaches. Adults live in much deeper water, normally between 30 and 60 m, although have been recorded at depths of around 90 m.
The longnose trevally is of minor importance to fisheries throughout its range, taken by hook and line, bottom trawls, gill nets and various types of trap. It is usually sold fresh, and is often not distinguished from other species of carangid. The species is occasionally caught by boat anglers, as well as beach fishermen on the South African coast. They take small baits and are considered good for eating.