Latin name

Atropus atropos

Other names

Cleftbelly kingfish, Kuweh trevally, thin crevalle.

Identification

The body is oval in shape, strongly compressed at the sides. The height of the body is 26.4-31.4% of the standard length of the body. 

The upper profile of the head is straight, rising steeply from the end of the upper jaw to the area above the eye, then becoming convex. 

The lower part of the thorax to the pelvic fins is scaleless. A median deep furrow runs along the bottom of the abdomen to the anal fin. 

The diameter of the eye is slightly more than the length of the snout; the fatty eyelid is absent. 

The small teeth on the upper jaw are arranged in a narrow band, widest in the anterior part. On the lower jaw, the teeth are arranged in a single row, with 2-3 irregular rows in the anterior part. 

The first gill arc has 29-34 gill stamens, of which there are 8-11 stamens on the upper part and 19-22 stamens on the lower part. 

The lateral line forms a high arc in the anterior part and then goes straight up to the caudal peduncle. The transition from the curved part of the lateral line to the straight part is on a vertical line in the area between the sixth and seventh soft rays of the second dorsal fin. The length of the chord of the curved part of the lateral line is 1.5-2.0 times the length of the straight part. There are 31-37 bony lobes in the straight part. 

Vertebrae: 10 dorsal and 14 caudal vertebrae.

Features of fish fins

Two dorsal fins. The first dorsal fin has 8 hard rays, while the second dorsal fin has one hard ray and 19-22 soft rays. Sexual dimorphism is observed in the shape of the dorsal fin: in mature males, the 6-12 central rays in the second dorsal fin are elongated into long filaments of varying lengths. The anal fin has one barbed and 17-18 soft rays, with 2 barbs in front of the fin. The anal fin also has five elongated rays. The pelvic fins are long, their ends reach the anus, and can retract into a furrow on the abdomen. The tail fin is bifurcated. 

Fish colouring

The upper parts of the head and body are bluish-green, the lower parts are silvery. The membranes of the pelvic fins are black; the bases of the rays are white. The remainder of the fins are pale. Juveniles have indistinct dark stripes on the sides of the body and a spot on the gill cover; the spot is visible in adults.

Distribution

Widespread in tropical and subtropical waters of the Indo-Pacific from the Persian Gulf, Pakistan, Sri Lanka and Malaysia to the Philippines, Papua New Guinea, Taiwan and southern Japan.

Habitat

Marine; tropical; pelagic-neritic; amphidromous fishes. Depth range from 5 to 100 meters. 

Size

Maximum length: 31.6 cm. The study was conducted in India and showed that the fish grows 12.4 cm in the first year of life and grows more slowly in the second and third years, adding 7.35 cm and 3.5 cm to its total length during these years.

Behavior

They inhabit coastal waters and swim near the surface. 

Food and feeding habits

Feeds on crustaceans (shrimp, copepods, decapod larvae); large individuals may consume small fish. 

Reproduction

First mature (50% of individuals in the population) at an average body length of 21 cm. They spawn off the coast of India in November-December.

Fishing

This species is of minor importance to fisheries throughout its range and is harvested primarily by trawls, traps, and various hook-and-line methods.

Relationship with a person

A harmless species for human consumption.