Face fish generally refers to four-fingered bamboo pod fish.

Eleutheronema tetradactylum (scientific name: Eleutheronema tetradactylum) is a kind of fish belonging to Equisetaceae. The body is slender and the side is flat. The head is big and the front end is round and blunt. This kiss is short and round. Eyes are large and located in front of the head; Obese eyelids are well developed and rectangular. The mouth is big, inferior, and the mouth crack is nearly horizontal; The mandibular lip is underdeveloped, and the lip structure is only preserved near the corner of the mouth; There are teeth on both sides of the upper and lower jaws, and small teeth on the outside; Hoes and palates also have teeth. The body is covered with comb scales, with scales on the back, buttocks and the base of pectoral fin, while the axillary scales on the base of pectoral fin and ventral fin are long and sharp, and there is another triangular scale flap between the two ventral fins. The lateral line is straight and slowly inclined backward, and the lateral line scale of the hole is 86 ~ 88; The black edge of dorsal fin and caudal fin is not obvious; The fin membrane of pectoral fin is bright yellow (dark yellow for large fish with a standard length of more than 35 cm); The front edge of the ventral fin is yellow, and the rest is white.

Four-fingered mackerel is a warm marine fish with euryhaline, which can live in fresh water, salty fresh water and seawater. I like to live in shallow sea areas and estuaries where the water depth at the bottom of sand or mud is less than 23 meters, and also enter the lower reaches of rivers. They are omnivorous and mainly feed on benthos. Young fish inhabit estuaries and feed on invertebrates such as cladocera, copepods, amphipods and isopods. Young horns with a body length of 50 mm feed on sagitta, cephalopod shrimp larvae and polychaetes. Adult fish feed on fish (mainly whitebait and grouper). Widely distributed in the northern Indian Ocean and the western Pacific Ocean, from the Persian Gulf eastward to Papua New Guinea and northern Australia, and northward to China and Japan. In China, it is distributed in South China Sea, East China Sea, Yellow Sea and Bohai Sea. In the waters of the Yangtze River estuary, it can be found in the north and south branches of the Yangtze River estuary, along the Chongming Dongtan, the Huihe Tidal Harbor north of Hangzhou Bay, the Beilin in Fengxian, and the Jinshanzui in Jinshan County.