Common name: milk fish. Eyes are big, fat eyelids are developed, and eyes are completely covered. There is a protuberance at the suture of the mandible. Two chins have no teeth. The left and right operculum membranes are connected in the abdomen, but separated from the isthmus. The round scales are small and the head is scaleless. The dorsal fin is located above the ventral fin and has a scale sheath at the base. There are axillary scales at the base of pectoral fin and ventral fin. It is a warm-water gregarious fish, which swims offshore during breeding. Like to jump. It has a wide range of salt tolerance and can live in fresh water. But the water temperature is inactive at 15℃, and it will die when it is lower than 10℃. As one of the fishes in Hong Kong, Taiwan Province Province, China began to raise fish as early as17th century. Because of its fast growth speed and few fry diseases, it is a promising salt and fresh water cultured fish. Distributed in Indian Ocean and Pacific Ocean. I was born in Nanhai and Nanhai.