Carp is a freshwater fish belonging to a good fish, scales white with a metallic luster, red tail, tender meat, fresh flavor, the Yellow River carp is particularly popular.
Grass carp, also known as grass green, body color tea yellow, for the most productive freshwater fish. This fish is characterized by fast growth, large weight, head big meat fat, but the meat is coarse, compared to carp and other quality is inferior.
The chub is divided into two types: white chub and silver chub (commonly known as fathead minnow). Chub body color white, scales small, head larger, meat fat, taste, the head of the most fat, especially suitable for making casserole fish head.
Carp, also known as crucian carp melon, flat and wide body shape, back bulge obviously, scales are smaller, its characteristics of tender meat, fresh flavor, but small thorns, crucian carp is most suitable for blanching soup. Small crucian carp is suitable for making crispy fish.
The mackerel is also known as the black fin, long body, cylindrical, black spine, belly milky white, white and full of meat, freshwater fish in the meat of a kind of tender; contains more fat, especially a section of pectoral fins and two parts of the meat of the head and tail, mackerel lungs are the most tender part of the fish body, contains more fat, the famous dish "roast bald lung" is The famous dish "Roasted Bald Lung" is made of mackerel lungs, roasted and eaten hot, rich and beautiful.
Eel, also known as long fish, eel, long and thin body, head thick tail thin, back black-brown, belly yellow, small eyes without scales, the meat of this fish is extremely tender and tasty, is regarded as the best fish.
Soft-shelled turtle fish, also known as soft-shelled turtle fish, tender meat, rich in nutrients, is a high-grade tonic.
Ornamental fish refers to those fish with ornamental value and bright colors or peculiar shapes. Usually there are three strains of ornamental fish, namely temperate freshwater ornamental fish, tropical freshwater ornamental fish and tropical saltwater ornamental fish.
Temperate freshwater ornamental fish are mainly red crucian carp, Chinese goldfish, Japanese koi. There are three major series of tropical freshwater ornamental fish, one is the lamprey species, the second is the fairy fish, and the third is the dragon fish. Seawater ornamental fish mainly from the Indian Ocean, the Pacific Ocean in the coral reef waters, many varieties, body color strange, with a kind of primitive and ancient mystery of natural beauty.
Keeping goldfish is one of people's common preferences, starting in the late 1980s, the ornamental fish market in Guangzhou gradually expanding, when almost every household has a fish tank, a "lion's head" dozens of dollars to hundreds of dollars, the first reveal the source of the aristocracy. But goldfish breeding is difficult, low survival rate and complex processes, fish farmers gradually reduced, the aquarium market to cultivate high-quality fish species for the mainstream, but also makes the price of noble goldfish the more high. Koi in the early 1990s became a goldfish star, a pricey koi sold to thousands of dollars, tens of thousands of dollars of varieties. Influenced by Hong Kong and Taiwan, the dragonfish in the koi after the overnight fame, body shape, color superior to sell to more than 30,000 yuan. But in recent years, the price of koi and red dragon has fallen back to a more stable level, a body shape, scale color, posture and respect for the adult red dragon sold for less than ten thousand yuan.
Currently, the aquarium market is the newest from Malaysia's "flower Luo Han" and Taiwan's "fluorescent fish", koi carp and dragonfish "status" has been "Flower Luo Han" has been replaced, the price of the best varieties to maintain more than 10,000 yuan, the price tag of more than 100,000 yuan of rare varieties also have. "Fluorescent fish" is a new species introduced early this year, this fish can emit a weak fluorescence in the dark environment, less than two centimeters in length of the small fish sold for 90 yuan The existing fish are divided into cartilaginous fish and bony fish two categories. Fish are the oldest vertebrates. They inhabit almost all aquatic environments on Earth - from freshwater lakes and rivers to saltwater seas and oceans. There are about 24,000 extant species of fish in the world. Two-thirds of them live in seawater, the rest in freshwater. China counts 2,500 species, of which there are more than 100 kinds of medicinal use, common medicinal animals are seahorses, sea dragons, eels, carp, crucian carp, sturgeon (swim bladder for swim bladder gelatin), rhubarb fish (otoliths of fish brain stone), sharks and so on. In addition, it is also commonly used as a raw material for the pharmaceutical industry, for example, the liver of cod, shark or ray is the main raw material for extracting cod liver oil (vitamin A and vitamin D). Hydrolyzed proteins, cytochrome C, lecithin and ceruloplasmin can be extracted from various fish. The liver and ovaries of river herring contain large amounts of tetrodotoxin, which can be extracted to treat neuropathy, spasms, tumors, and other conditions. The bile of large fish can be extracted to make "calcium salt of bile pigment", which is the raw material for the artificial manufacture of oxalic acid. Fish live all their lives in seawater or freshwater, and most of them have a body shape and fins suitable for swimming. They breathe through gills and feed with their upper and lower jaws. Appeared to be able to beat the heart is divided into an atrium and a ventricle. Blood circulation is unicirculatory. The emergence of the spine and the head led to the development and evolution of the order Ichthyophagy into the group of vertebrates best adapted to life in water. This is due to the fact that there are depths and depths of water and differences in the pressure exerted at each location, from 1 atmosphere at sea level to up to 1,000 atmospheres in deeper areas. The salt content of fresh and salt water ranges from 0.001 to 7% from fresh water to brackish water. In addition, with the different geographical environment, the water temperature difference and oxygen content of the difference is also very large. Because of the diversity of these waters, water layers, water quality and biological and non-biological factors in the water and other aquatic environments, so the body structure of the fish to adapt to different changes in the outside world to produce different changes. Higher than Cirripedia. Ichthyoplankton is the largest of the existing vertebrate subclasses. From the point of view of animal evolution, this class is the beginning of the jawed class, so it is the most primitive and the oldest class of the jawed class. This is the largest taxonomic group in the subphylum of vertebrates, which has derived many marginal clades as far back as the Devonian period, and has developed and evolved into a variety of fish with complex body shapes. The existing fishes are divided into cartilaginous and scleractinian lineages. I. Chondrichthyes is the lowest class of existing fishes, there are more than 200 kinds of fishes in the world and more than 140 kinds of fishes in our country, and most of them live in the sea. Its main characteristics are: ① lifelong no hard bone, the endoskeleton is composed of cartilage. Most of the body surface is covered with tatty scales. The body surface is mostly covered with tatty scales. ③ Gill intervals are well developed and there is no gill cover. (iv) Crooked caudal fin. This lineage*** is divided into two subclasses, i.e., Plate Gill Subclass and Holoproct Subclass. II. Osteichthyes (Osteichthyes) Osteichthyes is the largest group of existing fishes in the world, with more than 20,000 species, most of which live in marine waters and some in fresh water. Its main characteristics are: ① the skeleton is hardened to different degrees into a hard bone. ② The body surface is covered with hard scales, round scales or pectinate scales, and a few species are degenerated without scales. The mucous glands of the skin are well developed. The gill septum is partially or completely degenerated, the gills do not open directly outside the body, there is a bony gill cover to cover the gills, the water flowing from the gill slits is drained away through the posterior edge of the gill cover, and most of them have swim bladders. Most of them have swim bladders. ④The tail of the fish is often orthotropic, and there are also proto-tails or crooked tails. ⑤ Most are fertilized in vitro and oviparous, and a few have metamorphosis in development. The earliest fish was a round-mouthed, jawless fish that appeared on Earth during the Cambrian period 450 million years ago. Fish are easily distinguished by their appearance, and they make up the largest group of vertebrates: there are more than 22,000 species of fish out of a total of 50,000 vertebrate species. Not all animals that live in water are fish. Whales, for example, are mammals. However, all fish are well adapted to life in water. They move with their fins. Fish have two pairs of fins - the pectoral and ventral fins, which are located on each side of the body; a caudal fin, which grows at the end of the tail; and, depending on the species, one or two dorsal fins on the back and an anal fin on the buttocks. They have a gas-filled sac, called a swim bladder, which enables the fish to sink, float, and keep their position in the water. Only rays and sharks do not have this organ. Fish also have gills that are used for breathing, and in most species the gills are covered by gill cover bones. Located on either side of the head, behind the mouth, the gills are used to filter water swallowed through the mouth, get oxygen from the water, and then expel the water through openings called gill slits. The size of different species of fish varies greatly. Their bodies consist of 3 parts: head, trunk and tail. The skin is covered with scales, which vary in size and number. On each side there is a distinct line called the lateral line, which is a sense organ and is used to determine direction. The muscles of some scleractinian fish are separated by a number of tiny bones. The first fish to appear on earth had round, jawless mouths, and only 70 such fish now exist, forming the jawless fishes. Of these fish, the seven-gill eel is the best known, with no scales and a slender, rounded body much like that of an eel. Seven-gill eels live by attaching themselves to other fish through their sucker-bearing mouths and sucking the blood of their hosts. The other fish are divided into two main groups: scleractinians and cartilaginous fish. Scleractinian fish have a skeleton. There are native scleractinians in this group of fish, where only a portion of the skeleton is hard bone. Examples include the finfish of the subclass Centrarchia (including the hollow-spined fishes), lungfish and sturgeons (e.g., Acipenser sturgeon), which differ from the more evolved scleractinian fishes in that the skeleton of scleractinian fishes is made up entirely of sclerotized bone. Moray eels, sole, and spiny capelin, as representatives of the bony fishes, vary in appearance, but all have extremely symmetrical caudal fins and are tracked with fine scales (with only a few exceptions, including eels and some carp). Scleractinians are divided into several groups. The eels are some of the fish whose juveniles look very different from the adults. The herring group are some of the fish that live a schooling life. The carp group contains almost all freshwater fish. River perch and tuna are fish whose tail fins are supported by hard spokes. They are called "spiny-finned" and form the largest group of bony fishes. Cartilaginous fish have a skeleton composed entirely of cartilage and reinforced by calcium. These are mainly sharks and rays. Eels are born as small, flat-bodied fish called "baby eels". At maturity they have a long, smooth body, generally scale-free, with a continuous fin along the back. Eels live in rivers and lakes in Europe and the Americas, and migrate to the sea of algae in the northeastern West Indies in the North Atlantic, where they reproduce. They die after their young are born. Baby eels take on their adult form on their way back across the Atlantic, and on their way back they also begin to give birth in the Sargasso Sea. Herring live in the North Sea, the English Channel and the Baltic Sea. Adults have a light-colored belly and a dark blue or nearly black back. Like sardines and western herring, they live in schools, sometimes several thousand fish living together. For each fish, this is an effective method of self-defense, since for a predator there is only one target among many. When attacked, the school of fish disappears almost immediately. There are thousands of species of fish belonging to the carp family, which are found almost all over the globe. These freshwater fish have large scales and their teeth are fixed not to the jaws but to the throat. Their mouths are able to move forward to suck in food. Many species in the genus Carp live mainly in calm rivers, small ponds and lakes in Asia and Europe, and the shape and coloration of individual species vary greatly. Some species have only a few large scales (mirror carp) or almost no scales (grass carp). These fish are easy to culture and many variations have been created by breeders. Carp feed primarily on plants and invertebrates. The spawning season depends on the temperature of the water, which should not be too cold (at least 20°C). Females produce hundreds of eggs, but most of the young fry become food for other fish and even adult carp as soon as they are born. Spiny fins appeared about 60 million years ago. Perch are typical of this group of fish, with their fins all held up by hard, sharp spoked ground and a huge caudal fin with spines. Perch live in lakes and rivers in Europe and North America, where they eat invertebrates and small fish, including their own young. Other species of these fish live in the oceans, such as tuna and swordfish, which are powerful swimmers and can swim up to 100 kilometers per hour. Tuna can weigh up to 500 kilograms and are predators. They are unique among fish in their ability to maintain a body temperature above that of the water, and their species include the albacore tuna in the Pacific and the bluefin tuna in the Mediterranean and Atlantic. Sharks and rays are the main representatives of modern chondrichthyans, which may have appeared as long as 410 million years ago. As their name suggests, they have a skeleton made of cartilage. Cartilage is a pliable material that hardens when filled with calcium and is solid like bone. Cartilaginous fish thrive in large numbers in temperate and hot oceans. They breathe in the water with gills. The gills communicate directly with the outside world through several gill slits at the back of the head. There are about 550 species of cartilaginous fish, of which 370 are sharks and the others consist essentially of rays and electric rays with flattened bodies.