large yellow croaker

(1) morphological features: the body of Pseudosciaena Crocea is elongated, flattened laterally, the dorsal and ventral edges are widely curved, and the tail stalk is slender. The body length is 4.2 times of the body height and 3.4 times of the head length. The length of the head is 5.0times of the length of the kiss and 5.7times of the diameter of the eye. The length of the caudal stalk is 3.4 times higher than that of the caudal stalk. The abaxial and upper sides are yellowish brown, the lower sides and ventral surfaces are golden, the dorsal and caudal fins are grayish yellow, the pectoral and ventral fins are yellow, and the lips are orange. The lateral side of the head is flat, large and pointed and obtuse, with a well-developed mucous cavity. The kiss is blunt, larger than the diameter of the eye. The snout fold is intact and unlobulated; the supraconasal foramen is quite small, 3, and sometimes disappears; there are 5 anastomotic foramen, the middle marginal foramen is round, and the lateral marginal foramen is cracked. The eyes are large and on the upper side, located in the front half of the head. The septum of the eye is round, larger than the diameter of the eye. There are 2 nostrils on each side, the anterior nostrils are small and round, and the posterior nostrils are large and oblong. Big mouth, anterior position, oblique crack. The lower jaw is slightly protruding and there is a tumor-like process at the suture. The posterior end of the maxilla extends above the posterior edge of the eye. The teeth are small and sharp, the maxillary teeth are multi-row, the external teeth are enlarged, the anterior teeth are the largest, the mandibular teeth are 2 rows, the internal teeth are larger, and the posterior 2 teeth with tumor-like processes in the mandibular suture are larger, and their tips are inward. There are 6 mental foramen, which is not obvious. The central mental foramen and the medial mental foramen are arranged in a square, and the lateral chin also exists. No mental foramen. The branchial pore is large. The margin of the anterior Gill cover bone is serrulate. There are 2 flat spines in the posterior and upper part of the operculum. The opercular membrane is not connected to the isthmus. Gill cover strip 7. With false gills. The Gill rake is slender, about 2 prime 3 in diameter. Gill rake 9: 16-17. The head and front of the body are covered with round scales, and the back of the body is covered with chlamys scales. The fin of the dorsal fin and the membrane of the anal fin are all covered with non-round scales, and the caudal fin is scaled. The dorsal fin and the lateral line are scaly in 9 rows. Each scale in the lower part of the body often has a golden gland. The lateral line is complete, the front is slightly curved, and the rear is straight, extending to the end of the caudal fin. The dorsal fin is continuous, with a deep concave between the fin spine and the fin strip, the starting point is above the base of the pectoral fin, with 9 Mel 10 fin spines, the first fin spine is short and weak, and the third fin spine is the longest. The anal fin has 2 fin spines, the starting point is below the middle of the dorsal fin strip, and the length of the second fin spine is equal to or slightly larger than the eye diameter. The tip of the pectoral fin is longer than the ventral fin. The ventral fin is smaller. The tip of the caudal fin is long and slightly wedge-shaped. The swim bladder is large, the front end is round, and both sides do not protrude into lateral sacs, and the swim bladder side has 31mur33 pairs of lateral limbs; each side has dorsal branches and ventral branches, the ventral branches are divided into upper and lower branches, and the inferior branches are divided into anterior and posterior small branches, which are equal in length and parallel to each other and extend to the ventral surface along the subperitoneum. The otolith is slightly textured and the ventral mask is tadpole-shaped. There are generally 26 vertebrae.

(2) Ecological habits: Pseudosciaena Crocea likes to inhabit the middle and lower layers of the coastal shallow area with a water depth of less than 60 meters, and clusters in the middle and upper layers during reproduction, which is a warm-temperate cluster migratory offshore fish. Dislike strong light, often concentrate in the muddy water area with less transparency, and float at dawn, dusk or spring tide. With a wide range of feeding habits, it is a predatory fish with as many as 100 kinds of prey. Juvenile fish mainly feed on zooplankton such as copepods, prawns, krill and so on. Adult fish mainly eat a variety of small fish, shrimp, crabs, prawns and so on. The feeding intensity decreased during the reproductive period. Pseudosciaena Crocea also has a strong vocal ability, and the spawning population during the reproductive period is accompanied by strong "winter" and "goo" calls. The sound made when a school of fish is dense is like the sound of boiling water or the sound of pine waves. The spawning ground of Pseudosciaena Crocea is mostly near the estuary or in the inshore shallow water area of the island and inner bay, the water depth is generally no more than 20 meters, and the sediment is ooze and sediment. Pseudosciaena Crocea can spawn many times in its life, the main spawning season is spring and autumn, and the spring tide flood season is its ovulation period. The number of eggs is 10-1.1 million, usually 20-500000. Pseudosciaena Crocea is mainly distributed in the South China Sea, Taiwan Strait, East China Sea and southern Yellow Sea, with the highest yield in Zhejiang.