The body is thick and flat and is spindle-shaped. It is generally 20 to 40 cm in length and 150 to 400 grams in weight. The head is large, the tip of the tip is conical, the eye is large, the mouth is large, the upper and lower jaws are the same length, each line has fine teeth, and the vomer and the cheekbones have teeth. The body is surrounded by small round scales, the back of the body is dark blue or dark blue, and there are irregular deep blue worms on the horizontal lines of the pectoral fins on both sides of the body. The abdomen is white and slightly yellow. There are 2 dorsal fins distant from each other, with 9-10 first dorsal fin spines, 2 dorsal fins and anal fins facing each other, and 5 small fins on the upper and lower sides of the dorsal fin; caudal fins with deep fork-shaped, two ridges on both sides of the base; pectoral fins Light black, light pink anal fins, other pale yellow fins.