What are the varieties of crabs? What are the varieties of crabs

Naturally growing river crabs are generally burrowing or secluded. When the food is abundant and full, they often live in caves in order to avoid predators. When burrowing conditions are not available, they hide in gravel or grass.

River crabs usually prefer to live in rivers and lakes with clean water and abundant aquatic plants, and when they are in ponds, they often hide in the silt at the bottom of the pond. River crabs lie dormant at night, settle down when the bait is abundant and the environment is suitable, and once mature, they abandon their burrows and leave. River crabs grow in freshwater and reproduce in seawater.

After entering fresh water, crab seedlings generally live in rivers and lakes with abundant bait for about 18 months, and their gonads gradually mature. Mature river crabs begin to spawn in the offshore areas where sea and fresh water mix in late autumn and early winter, which is known as reproductive migration.

There are many types of crabs, there are about 600 kinds of crabs in China, there are pike crabs, blue crabs, frog crabs, Guan Gong crabs, etc., because of the different geographical locations of distribution, so there are also grades, the first class is lake crabs, such as Yangcheng Lake, Jiaxing Lake; the second class is river crabs, such as Jiujiang and Wuhu; The third class is river crabs; The fourth class is brook crab; The fifth class is the ditch crab; The sixth class is sea crabs.

King crabs, lamb crabs, hairy crabs, pike crabs, river crabs, and more! ~~

River crabs belong to the phylum Arthropods, Crustaceans, Decapods, Reptiles, Brachytails, Square Crabs, Bowleggys, and Mitten Crabs. There are four species of mitten crabs in China, namely Chinese mitten crab, Japanese mitten crab, narrow-fronted mitten crab and straight-fronted mitten crab (Figure 2-1). Narrow-fronted mitish crab and straight-fronted mitten crab are not only small in individuality, but also small in yield, and have no economic value. Chinese mitten crab and Japanese mitten crab are usually called river crabs, hairy crabs, crabs, clear water crabs and hairy crabs, etc., which are large, good meat quality and high yield.

The main differences between them are:

Figure 2-1 Morphological comparison of four species of mitten crabs.

1) Chinese mitten crab.

The cephalothorax is distinctly raised, the frontal margin has 4 sharp teeth, the gap between the teeth is deep, the middle one is the deepest, there are 6 wart-like protrusions behind the frontal horn, the anterior lateral margin has 4 teeth, the 4th side teeth are small and distinct, and the toe nodes of the last pair of feet are pointed and claw-like.

2) Japanese mitten crab.

The cephalothorax is not distinctly raised, the frontal margin has 4 sharp teeth, but the middle two teeth are round and blunt, the outer two teeth are sharper, the interdental gap is shallow, the middle one is the shallower, there are 4 wart-like protrusions behind the frontal horn, the anterior lateral margin has 3 teeth, the 4th lateral tooth is vestigial, and the toe segment of the last 1 pair of feet is broad and flattened.

Chinese mitten crab is distributed in the coastal provinces of the Bohai Sea, the Yellow Sea and the East China Sea in China, and it has two populations, among which, the northern population is represented by the Liaohe (Yellow River) water system crab, and the southern population is represented by the Yangtze River (Oujiang River) water system. Japanese mitten crab is mainly distributed in Guangdong, Guangxi, Fujian, China's Taiwan coast, Japan coast, Russian Far East, it is also divided into two populations, among them, the northern population is represented by the Suifen River system (locally known as "Russian crab"), and the southern population is represented by the Nanliujiang River system (commonly known as "Hepu crab").

The results showed that after the transplantation of the crab to the Yangtze River system, it was not adapted to the growth environment of the middle and lower reaches of the Yangtze River, and the commercial crab matured one month earlier (late August), and its molting times were small, and the individual was small and the quality was poor. What's more serious is that the Liaohe River system Chinese mitten crab and Japanese mitten crab are mixed, unfortunately, China's "big crab farming" in the past ten years, the crab seedlings and crab species of different water systems or different populations are transplanted to other places for breeding, resulting in the mixing of river crab germplasm resources in various water systems, and the loss of its intangible assets is immeasurable.

Therefore, it is strictly forbidden to transplant river crabs from different water systems to other water systems for breeding.

There are about 600 kinds of crabs, and among them, there are more than 10 kinds of flower crabs, pike crabs, red crabs, brown crabs, crystal crabs, three-point crabs, asahi crabs, river crabs, stone crabs, blue crabs, king crabs, hairy crabs, Dungeness crabs, and sand mother crabs. At the seafood market, it is possible to see them. The resources of crabs in China are very rich, according to the preliminary understanding, there are about 600 species.

Among them, the hairy crabs produced by Taihu Lake hairy crabs, Gaoyou Lake hairy crabs, and Yangcheng Lake hairy crabs in the lower reaches of the Yangtze River are the top grades. In addition, blue crabs and river crabs are also relatively common in our lives.

There are about 600 kinds of crabs, and among them, there are more than 10 kinds of flower crabs, pike crabs, red crabs, brown crabs, crystal crabs, three-point crabs, asahi crabs, river crabs, stone crabs, blue crabs, king crabs, hairy crabs, Dungeness crabs, and sand mother crabs. At the seafood market, it is possible to see them. Barracuda crab, commonly known as "white crab" in some places.

Because the cephalothorax is a shuttle, it is called a shuttle. The ** of the carapace has three protrusions, so it is also called "three-wart pike crab", which belongs to arthropods. Males have a pointed and smooth umbilicus, with long chelae and a bluish shell surface; The female has a round umbilicus with villi hairs, and the shell surface is ochre or spotted.

The crab meat is fat and delicious, has high nutritional value and economic value, and is suitable for temporary breeding and fattening of seawater.

There are many kinds of crabs, there are pike crabs, blue crabs, frog crabs, Guan Gong crabs, etc., because the geographical location of the distribution is different, so there are grades, the first class is lake crabs, such as Yangcheng Lake, Jiaxing Lake. the second class is river crabs, such as Jiujiang and Wuhu; The third class is river crabs, the fourth class is river crabs, the fifth class is ditch crabs, and the sixth class is sea crabs.

The varieties of crabs include king crab, flower crab, brown crab, giant crab, Yangcheng Lake hairy crab, Tianjin purple crab, pike crab, blue crab, frog crab, Guan Gong crab and so on. King Crab: King crabs are also known as the "king of crabs" due to their large size and the fact that they are found in very deep waters.

Flower crab: Flower crab is a kind of crab with patterns on the shell, hence the name, flower crab has a high requirement for water temperature. Brown crab:

Also known as "mantou crabs", their shells are only 6-7cm long and 8-9cm wide. <

The varieties of crabs include king crab, flower crab, brown crab, giant crab, Yangcheng Lake hairy crab, Tianjin purple crab, pike crab, blue crab, frog crab, Guan Gong crab and so on.

1. King crab: King crab is also known as the "king of crabs", this is because of their relatively large size, from the point of view of distribution waters, king crabs are distributed in very deep seawater.

2. Flower crab: Flower crab is a kind of crab with patterns on the shell, hence the name, from the distribution range, the flower crab has higher requirements for water temperature.

3. Brown crab: It is also called "steamed crab", this kind of crab is relatively small, the length of their shell is only 6-7cm, and the width is only 8-9cm.

4. Giant crab: Giant crab is the only species of giant crab in the family Decapoda short-tailed spider crab. The body is dark orange, with ten long limbs with white spots, and the first two limbs develop into chelicera.

5. Yangcheng Lake hairy crab: a special product of Suzhou City, Jiangsu Province, and a product of China's National Geographical Indication. Yangcheng Lake hairy crab is also known as golden claw crab. It is produced in Yangcheng Lake, Suzhou.

6. Tianjin Purple Crab: It is a kind of Chinese mitten crab, which is small and only the size of a coat button. When the crab lid is removed, the crab roe is purple in pork liver, and when cooked, it turns orange-red, and the taste is extremely delicious.

Flower crab: also known as the open sea pike crab, the shell is distributed with irregular patterns. Champagne Crab:

The body color is champagne and the tip of the crab claw is black. Seed crabs: Produced in Japan, Russia, and North Korea, they are all female crabs.

Hairy crab: also known as Chinese mitten crab and hairy crab, it is the main aquaculture species in China with a high yield. Spider Crab:

Native to Alaska, USA, it is similar to spiders.

1. Flower crab

Flower crab refers to the open sea pike crab, named because of the irregular pattern distributed on the shell, belongs to the warm-water crab, mainly distributed in Zhejiang, Fujian, Guangdong, Hainan, Taiwan and other places in China, the length of the male chelicerae is 4 times the length of the cephalothorax, and the front end of the female cephalothorax is dark green, and the back end is yellow-brown.

2. Champagne crab

Champagne crab is also called Australian spiny crab, its whole body color is light, champagne color, dense hairs and protrusions are distributed on the foot, the front end of the chelicerae is black, the middle and rear ends are distributed with dark brown spots, the cephalothorax is oval, and the surface is uneven.

3. Seed crab

Seed crab is a kind of crab produced in the waters of Japan, Russia and North Korea, living in an area with a depth of less than one kilometer, the adult seed crab is only kilograms, the color is light blue, and the limbs are not developed, all belong to the female crab, at present, only North Korea can be fished in batches, and the rest of the countries are prohibited from fishing.

4. Hairy crab

Hairy crab, also known as Chinese mitten crab, is a kind of freshwater crab with the largest production in China, belongs to the main aquaculture species, originated in China, and then reached Germany with the ship, and is currently distributed in many European countries, its head and thorax are wide round, the back is blue-gray, and the meat is fresh and tender.

5. Spider crab

Spider crab belongs to sea crabs, produced in Alaska, USA, because the crab legs are extremely long, similar to the spider and get the name, its shell is hard, the body is thick and round, slow to move, mostly feed on animal carcasses, with more protruding balls on the back, is a sea anemone parasitic on the shell of the spider crab.

There are many varieties of crabs, and there are more than 600 species in total. Depending on the living environment, crabs are divided into two types: sea crabs and freshwater crabs. Among them, flower crabs, blue crabs, pike crabs and other species live in the sea and belong to sea crabs.

Hairy crabs, crystal crabs and other species can live in freshwater and belong to freshwater crabs.

About Hairy Crabs:

Hairy crab belongs to the Chinese mitten crab, which is also called river crab, hairy crab, clear water crab, hairy crab. Hairy crabs and other crabs are mainly different in appearance and meat quality, the appearance of hairy crabs is green back, white belly, yellow hair, golden claws, its meat is delicate and delicious. Crabs are rich in protein and trace elements, and eating them in moderation has a good tonic effect on the body.

From September to October every year, the crab roe is full of oil, so some eaters say that "eating crabs is the most solemn thing in autumn". In autumn, the crabs are about to start preparing for the winter, they will eat a lot of food, continue to energy, and the meat will begin to be full.