Beluga Chinese commonly known as: elephant fish, swordfish, sturgeon, column anglerfish, ancient tuna.
A Gadiformes polyodontidae paddlefish genus. Named after the color is shallow. Fish, also known as Qin towards the ancient name of swordfish, tuna. Body long spindle shape. Kiss sword shaped, narrow and flat front, base hypertrophy. No bone plate hard scales; only in the caudal margin with a row of fulcra, back, abdomen and the purple gray fin slightly white pink. Located in the Yangtze River, the Yellow Sea and the East China Sea coast also found that ancient of Fenwei basin. Semi anadromous fish. Inhabits the Yangtze River, even along the river into large lakes. The fecundity is up to 200 thousand and the spawning site is in the Yibin area along the upper Yangtze River. Weight up to 500 kg. But generally more than 100 kg. Feed on fish.
Is Chinese paddlefish unique large-scale economic fish, is listed as a rare animal protection. 2 and distributed in North America of the Mississippi paddlefish for undergraduate only. The fishes in the fish origin, evolution and geographical distribution, has important academic value.
The body length, fusiform, slightly flat front, middle thick, slightly compressed at the rear. The length of the head is longer than half of the body length, and the upper part of the head is provided with a plum shaped trap. A sword like, especially extended, narrow and flat front end, base broad and hypertrophic. Kiss the ventral to the head can be freely telescopic. The ancient books "from the mouth under the jaw, long nose cartilage also" records, the ecological characteristics of Paddlefish made a concise summary. On the mandibular tapering denticulate; in short, one must kiss, ventral. Small eye. The film surface covered head organizes many fine plum sensory nerve cells. Gill pore large, smooth body without scales. In the upper lobe of caudal fin with 8 prism apron, backward to the upper lobe of caudal fin. The starting point in the ventral dorsal fin, are composed of unbranched rays. Heterocercal caudal fin, upper lobe developed, with a front column fulcra. Short bowel, intestinal 7-8 spiral valve. Head, body and tail back bluish grey, white belly.
Semi anadromous fish eggs. Inhabits the Yangtze River in the lower, I also along the river into large lakes, large individual habitat in the river deep water channel, good at swimming, cruising in the river water in the vast Yangtze River; tributary, juveniles were often harbor, even the brackish water area of Yangtze River feeding. Whether the Chinese sturgeon like beluga like sea on growing, it is unclear; but from the existing data analysis, but also can not be sure it is a kind of river sea migratory fish. Large ferocious fish eggs, fish and fish to fish for food, but also eat small shrimp and crab animal. At the same time a large white sturgeon fish. Age of first sexual maturity was 7-8 years, the length of the individual is generally around 2 meters, weighing more than 25 kg. According to a famous zoologist Professor Bing Zhi more than and 50 years ago records, had captured a 7 meter long tail heavy thousands of pounds of individuals in Nanjing, so far it is still the world's highest record of freshwater fish body length. Sichuan fishermen also have "Jack La Zi (Chinese sturgeon) as million pounds (Bai Xun)". Eggs the reproductive season in about 3-4 months, in Sichuan province Luzhou spawning sites, fast flowing velocity of about 0.49 M / s, the water depth of 10 meters, bottom rocky or pebble River, relatively concentrated spawning grounds in Jiangan County near the river near the Yangtze River and Yibin Cypress Creek in Jinsha River. The mature egg egg, the egg was gray with water rafting development, to the mouth of the Yangtze River on growing juveniles.
Located in the Yangtze River downstream paddlefish, also can be in the estuary brackish waters survival. In the past, the Qian Tang River in Zhejiang has been found, may be bypassing the Yangtze River Estuary and enter. Annual output of about twenty-five thousand kg. Over the past ten years, due to overfishing and other reasons, resources are declining, now endangered.