CATDOLL : CATDOLL: Why are some shrimps red and black while others are pale white? What species are they?

Jiwei shrimp: Jiwei shrimp refers to shrimp produced in the Jiwei area, which is a small river or creek near the coast. Fishermen bring in a lot of seawater from the river, and the seawater already contains sperm and eggs of shrimp. They are raised together and grow into Jiwei shrimp. They grow on the muddy bottom of the river and have a slightly dark body.

Sea shrimp: From the explanation of the sea shrimp, we know that the sea shrimp and the river shrimp belong to the same species. The only difference is that the sea shrimp grows in the sandy sea and has a red body. However, the taste of both is better, both are fresh and delicious.

Red rice shrimp: The price is relatively cheap, and the taste is also good when simply blanched. The characteristic is that the body is long and thin, with red spots on the body. There are two types: marine and farmed. Of course, the marine ones taste better. The shell is thin and easy to eat.

Bamboo shrimp: Also known as flower shrimp, bamboo shrimp, tiger shrimp, Japanese shrimp, and tiger shrimp. It is similar to tiger shrimp. It has long spines protruding forward on its head with fine serrations, and a thorn-like protrusion between its eyes. It has blue horizontal stripes, yellow appendages, and a bright yellow tail with blue. The shell is thin and hard, and the meat is thick.

Spring shrimp: Fishermen call it "white bean shrimp" or "pearl shrimp". Its characteristic is that its abdomen is full of eggs, some of which are red, purple, blue, etc. It is a product between salt water and fresh water. These shrimps can be found in the Yangtze River estuary in the mainland, Deep Bay in the northwest of Hong Kong's New Territories, and the Pearl River Estuary.

Mantis shrimp: The common mantis shrimp in Hong Kong are "Mantis scapula" and "Black Spot Mantis scapula", which can be simply divided into the former, which is the hard-shelled one that is often eaten, and the latter, which is the soft-bodied one with zebra stripes. They are produced in the "Fenliu Cape" area near Lantau Island in Hong Kong, adjacent to the bay and the Pearl River Estuary. However, many of them are now airlifted from Indonesia or Thailand. They are slightly dark in color, but of course they are less fierce than local products.

Mantis shrimp: There are many types of mantis shrimp on the market. The most common one is called cicada shrimp, also known as piglet shrimp. People in Hong Kong also call it thunder shrimp, and Taiwanese call it mantis shrimp. It looks fat and interesting. Its claws are thick and short, dark red, its forehead is flat and pentagonal, and its shell is hard and thick. The meat is fresh and delicious, and it is often used to make salad.

Tips: Teach you how to choose fresh mantis shrimps. Mantis shrimps with a turquoise back are fresh and have delicious meat. If the shrimp body turns yellow, it is the prelude to death. Although the claws will open and the mouth will move, the meat will start to "leak". After a period of time, the back will turn light yellow to pale yellow, the shrimp body will "melt into water", and the meat will become "hard" and inedible.

References: Online information

Freshwater shrimp farming species

There are 2,640 known shrimp species in the world, belonging to 39 families, and they are closely related to crabs, crab shrimps and lobsters. Shrimp are characterized by a translucent body, a soft and flexible abdomen connected to a fan-shaped tail. The appendages have evolved to be suitable for swimming. They have long antennae.

Freshwater shrimp farming includes freshwater shrimp farming and marine shrimp desalination farming. The main freshwater shrimp farming varieties in my country are: Macrobrachium nipponense, Macrobrachium rosenbergii, and freshwater lobster.

Swamp prawns in Japan are also commonly known as green shrimps. They belong to the subclass of Soft Shells, the order of Decapoda, the order of Parasitism, and the family of Long Arms. Swamp prawns are mainly distributed in Japan and my country. They are also an important target for freshwater fishing in my country. Except for the western plateau area, they are widely distributed in lakes, rivers, reservoirs, ponds and ditches across the country. They have the characteristics of omnivorous diet, fast growth, high reproduction and strong disease resistance. The water temperature for green shrimps to survive is between 0 and 34℃, and they enter the wintering period when the water temperature drops below 8℃. The spawning period is from May to September, and the reproduction begins when the water temperature is between 18 and 20℃. After three to four months of careful breeding, most of the bred shrimp fry can reach the market size of four to five centimeters. Jiangsu, Zhejiang and Shanghai are the main areas for green shrimp breeding and consumption.

The origin of Macrobrachium rosenbergii is the Indo-Pacific Ocean. Macrobrachium rosenbergii has different habitat habits at different growth stages. During the larval development period, it must survive in brackish water with a salinity of 8‰-22‰. Juveniles and adults live in fresh water. The survival temperature is 15 to 35℃, and the optimum growth temperature is 22 to 32℃. Adult shrimps have no restrictions on salinity and can live in fresh water or brackish water with low salinity. They like to live in the lower reaches of rivers affected by tides and in lakes, canals, paddy fields and other waters connected to them. After being cultured in ponds for about five months, the body length reaches eight to nine centimeters and the weight reaches twenty to twenty-five grams. Juveniles and adults mostly live alone, mostly distributed at the edge of the water, and like to cling to water plants, branches and other objects, and sometimes move in the water.

At present, the main species of freshwater lobsters cultured in my country are red crab shrimp, Yabi shrimp and Procyon clarkii shrimp;

Protocratidae is native to Central and South America and northeastern Mexico. It was introduced to my country from Japan in the 1930s and has now spread to Anhui, Shanghai, Jiangsu, Hong Kong, Taiwan and other places, forming a large number of natural populations. Protocratidae resembles shrimp but has a hard shell. The adult is about 5.6-11.9cm long, dark red, with a nearly black shell and an oblique stripe on the back of the abdomen. The body of the juvenile is uniform gray, sometimes with black ripples. It is a crab, narrow and long. The middle part of the shell is not separated by mesh-like gaps, and there are obvious granules on the shell. It can grow in salinity of 3‰ to 9‰; it can withstand high temperatures of 40℃ and low temperatures of -15℃. It has strong reproductive ability.

Red crab shrimp, also known as Australian lobster, freshwater lobster, crayfish. Originally a wild species in Australia, Australia began to carry out artificial breeding in 1971. It looks like a lobster and is one of the best freshwater farmed shrimps in the world. The shrimp can live in rivers, lakes, and ponds. It is benthic and crawling, and can survive in brackish water. It is omnivorous and feeds on organic debris, aquatic plants, aquatic insects, small benthic animals, fermented cow dung and artificial compound feed. The optimum water temperature is 22-32℃. The extreme water temperature is 4℃ and 37℃. It can crawl out of the water to save itself when the water quality deteriorates. The largest individual in nature is 500 grams. The seedlings can grow to 60-100 grams in artificial breeding, and the 2-year-old male shrimp can grow to 280 grams. It can reproduce naturally and lay eggs 1-2 times a year in the northern region.

The yabi shrimp has a strong drought resistance. Both shrimp and shrimp fry can survive for a long time in a humid (waterless) environment. Yabi shrimp are not good at swimming. They mostly crawl and live at the bottom of the pond. They like to hide in the gaps between bricks and stones. They like to cluster under the water grass, hide during the day and come out at night, and do not like strong light. The survival temperature range of yabi shrimp is 5-35 degrees, and the suitable growth temperature is 13-28℃. When the water temperature exceeds 13℃, it will start to eat, grow and reproduce. When the water temperature exceeds 30℃, it will inhibit growth and even cause death. It has a strong resistance to hypoxia. Adult shrimp can survive in water bodies with a certain salinity (below 17%‰). Yabi shrimp is omnivorous and can eat plant baits, such as green vegetables, grains, plant debris, etc., and can also eat animal baits, such as earthworms, insect larvae, snails, small fish and shrimp, tadpoles or other meats.

The species of marine shrimps that are cultured in a desalinated manner include the whiteleg shrimp.

The white shrimp is native to the coastal waters of the Central and South Pacific Ocean from northern Peru to Sanola, Mexico. It is currently recognized as one of the three most productive shrimp species in the world. It has the advantages of strong resistance to stress, wide salt tolerance, low nutritional requirements, high meat yield, delicious meat, and long survival time out of water. The water temperature for the growth of white shrimp is between 15 and 38°C, and the optimum water temperature is between 22 and 35°C. Below 18°C, feeding activities are affected, and death occurs when lying on the side below 9°C. It can also grow in waters with a salinity of 0.5‰ to 35‰, and can also be cultured in pure freshwater ponds after being tamed by desalination.

In addition, Penaeus razorfin and Penaeus monodon are also species of marine shrimp that are farmed in a desalinated manner.

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I recommend you to read this book

"Healthy Freshwater Shrimp Farming Technology" / New Technology Series on Healthy Aquaculture

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Crayfish (freshwater lobster) breeding technology

1. Basic habits of freshwater lobsters Freshwater lobsters, scientifically known as Procambarus clarkii, are also known as lobsters, big lobsters, and big red shrimps.

The shrimp originated in the United States and was introduced to my country from Japan during World War II. It is now widely distributed in the middle and lower reaches of the Yangtze River. The shrimp belongs to the warm tropical freshwater shrimp, with strong adaptability, high reproduction rate, miscellaneous diet, fast growth, disease resistance, high temperature resistance, low oxygen resistance, and will not die even if it is out of water for several hours. The shrimp meat is tender and nutritious, containing 8 essential amino acids for the human body, but with a low fat content, and contains more tropomyosin and paramyosin, and the edible part is high. It is deeply loved by domestic consumers, and the export volume is also increasing day by day. The sales and purchase prices are constantly rising, and the breeding prospects and benefits are optimistic.

Freshwater lobsters live widely in freshwater lakes, rivers, ponds, ditches, rice fields and other waters. Benthic organisms, plankton and various aquatic plants are all palatable baits, and they grow well in these waters.

Young shrimps live in shallow waters or pools, and like to live in caves. Sometimes they hide in hidden places among gravels and water plants. Usually, shrimp holes are dug in the reed-covered beach areas around large water surfaces with more clay and swamps. Shrimp holes are generally round, tilted downward, up to about 30 cm deep, and have different winding directions. Freshwater lobsters often move seasonally in their habitats. In spring, when the water temperature rises, shrimps mostly move in shallow waters; in midsummer, when the temperature is not high, they move to deep waters; in winter, they hibernate in caves. Freshwater lobsters also molt, grow, and reproduce in caves to prevent being hurt. Moreover, the shrimps like shade and fear light, and crawl out of the caves when the light is weak or dark. In the rainy season, freshwater lobsters often climb onto land to move around. The shrimps also have a strong ability to withstand hunger, and can generally withstand hunger for 3 to 5 days; in autumn and winter, they will not starve to death even if they do not eat for 20 to 30 days. The optimum temperature for feeding is 25-30℃; the activity decreases when the water temperature is below 15℃; the feeding decreases significantly when the water temperature is below 10℃ or above 35℃; when the water temperature is below 8℃, the lobster enters the wintering period and stops feeding. The life span of male freshwater lobsters is generally 20 months, and that of female lobsters is 24 months.

Freshwater lobsters usually mate and lay eggs between the end of October and March of the following year. The mating time varies in different waters. If they mate too early, the eggs are often immature, while if they mate too late, the eggs are overmature and old.

The suitable water temperature for mating is 22~25℃. It is best not to catch them during the mating season, so that they can hatch and reproduce. Freshwater lobsters mate in spring, summer and autumn, and can lay eggs 3~4 times a year. Generally, the parent shrimps with a body length of 7~10 cm and a weight of 15~30 grams can carry 220~270 eggs, and the number of eggs varies greatly depending on the size of the individual. Under normal circumstances, the egg-carrying shrimps after mating and spawning need a 1~2 month incubation process (i.e. embryonic development), which requires a lot of physical energy, so it is necessary to strengthen the nutrition and cultivation of the egg-carrying shrimps. The suitable water temperature for hatching egg-carrying shrimps is 22~27℃, and the incubation time is 6~10 weeks. Before the shrimp fry are cultivated, the pond needs to be cleaned and disinfected, the water needs to be filtered, and then organic fertilizers are applied to cultivate natural bait organisms for the shrimp fry to eat. Generally, the stocking density of juveniles during shrimp fry cultivation is 150,000~200,000. If the "soy milk" method is used for cultivation, the stocking density can be 160,000~180,000.

2. Lobster farming technology Lobsters can be farmed in ponds that are used to farm Japanese swamp prawns. Ordinary ponds can also be used for farming. The farming technology after stocking is similar to that of Japanese swamp prawns, including preliminary preparations, feed placement, and water quality management. However, attention should be paid to their habit of burrowing, and anti-escape measures also need to be strengthened. Lobsters have strong endurance and high production. The current market demand is also large, and the economic benefits of farming are considerable. The most common shallow water rice field farming is introduced below as an example, and other farming methods can be referenced.

3. Freshwater lobster farming in rice fields Freshwater lobster farming in rice fields generally produces 400-500 kg per mu, and can reach 600 kg at high yields. Shrimp farming in rice fields can eat weeds and other aquatic organisms that consume fertilizers in the fields, which not only saves labor for weeding, but also eliminates mosquitoes and flies that harm people and livestock. In addition, shrimps keep moving and foraging in rice fields, which not only helps loosen the soil, activate water, ventilate, and increase the dissolved oxygen content of field water, but also excretes a large amount of feces through metabolism, which has the effect of preserving fertilizer and increasing fat.

1. Selection of rice fields: To raise freshwater crayfish in rice fields, you must choose rice fields with sufficient water sources, not affected by droughts and floods, fresh and pollution-free water, fertile soil, good water retention performance, and sufficient sunlight. Although the water quality of some mountain streams or springs is relatively poor and the water temperature is relatively low, if they can have a longer flow or pass through rice fields where shrimps are not raised and then flow into shrimp-raising rice fields, the water temperature will increase and it will also be suitable for shrimp farming.

2. In order to facilitate production management and daily feeding, the area between drainage channels is generally used as a breeding block. A circulation buffer ditch with a depth of 0.5~0.6 meters and a width of 1.0~1.2 meters is dug 0.6 meters from the inner side of the surrounding ridges, and all the soil is turned over to the side ridges, so that the side ridges reach 0.8~1.0 meters high and 0.6~0.8 meters wide. The side ridges should be compacted and the inner slopes should be flat.

At the same time, a closed protective wall is built on the inner side of the ridge top with plastic film. The fence is 0.4~0.5 meters above the ground and buried 0.1~0.2 meters underground. Anti-escape nets should be set up at the upper and lower inlets and outlets.

In order to facilitate shallow irrigation, field drying, application of fertilizers and pesticides or fishing in rice fields, shrimp ditches and shrimp ponds must be dug in shrimp-raising rice fields.

Shrimp ditches can be dug after transplanting rice seedlings. The digging method should be determined by the shape of the field, the size of the field and the direction of the drainage outlet. If the rice field is small, it can be dug into a "field" shape; if it is a long and large field, it can be dug into an inner "well" or inner "field" shape. The width and depth of the ditch should be 0.3~0.4 meters respectively. Shrimp ponds can be dug at the intersection of shrimp ditches or at the four corners of the field, connected to the shrimp ditches. Shrimp ponds are generally 1.0 meters square and 0.8~1.0 meters deep.

When raising shrimp in rice fields, the inlet and outlet should be well opened. The location should be selected on the earthen ridges at the two opposite corners of the rice field. During the breeding process, the water in and out of the rice field can flow smoothly. Fences should be set at the inlet and outlet to prevent shrimp from escaping.

3. Stocking time of shrimp: Whether it is the shrimp of the current year or the parent shrimp with eggs, we should strive to release them early. Early stocking can not only prolong the growth period of shrimp in the rice field, but also make full use of the large amount of natural bait resources cultivated after fertilizing the rice field. The conventional stocking time is generally in November each year or the end of March of the following year.

Stocking density: 30-40 kg of broodstock with eggs are stocked per mu of rice field. You can also wait until April or May of the following year to stock young shrimps, with 12,000 to 15,000 shrimps per mu of rice field. Note that broodstock with eggs should be directly raised in the outer ditch for wintering, and then the shrimps can be lured into the rice field for growth when the rice seedlings turn green. There are two general breeding and stocking modes:

(1) Summer stocking: mainly stocking juvenile shrimps artificially bred that year. The stocking period is from July to September. 15,000 to 20,000 juvenile shrimps are stocked per mu of shrimp ditch.

(2) Winter stocking: usually carried out in December, 10,000 to 15,000 shrimps of about 3 cm in diameter are stocked per mu of shrimp ditch. In places where conditions permit, shrimp farming can be carried out in two seasons, one season of raising green shrimps from July to October, and one season of raising freshwater lobsters from December to May to June of the following year.

4. Feeding and Management (1) Feeding: When raising shrimp in rice fields, feeding should be done at regular times, in designated locations, with fixed quantities and quality.

In the early stage, feed once in the morning and afternoon; in the later stage, feed at around 6 pm. The types of bait are mostly small fish, snail meat, clam meat, earthworms, animal offal, silkworm pupae, corn, wheat, and barley flour. You can also feed an appropriate amount of plant feed, such as water hyacinth, water duckweed, and water duckweed. The daily feed amount is 3-5% of the shrimp's body weight. Usually, you should keep checking the shrimp's eating situation. If the bait fed on the day is eaten within 2-3 hours, it means that the amount of feed is insufficient, and the amount of feed should be appropriately increased. If there is still some left on the second day, the amount of feed should be appropriately reduced.

(2) Eliminate pests: There are many pests in rice fields, such as centipedes, snakes, water birds, eels, water rats, etc.

In the early stage of shrimp release, the rice stems and leaves are not lush, and the gaps in the water surface of the field are large. At this time, the shrimps are also small, with weaker mobility and poorer ability to escape from enemies, making them easy to be attacked by enemies. At the same time, freshwater lobsters need to molt every once in a while to grow. When they are molting or just molting, they are most likely to become palatable bait for enemies. At the harvest time, due to the shallow drainage of the field water, the shrimps may crawl everywhere, making them bigger targets and easy to be preyed on by birds and beasts. In this regard, it is necessary to strengthen field management and drive away enemies in time. In addition, after the shrimps are released, domestic ducks should be prohibited from going into the field ditches to avoid losses.

(3) Field ditch management: After shrimps are released, it is very important to manage the field ditches well.

In the early stage of shrimp farming, the water in the field should be shallow, but because the shrimps continue to grow and the rice heading, flowering, and filling all require a lot of water, the water in the field can be gradually deepened to 12~15 cm to ensure the water requirements of both (shrimp and rice). At the same time, pay attention to the changes in the water quality of the field ditch. Generally, new water is added every 3~5 days; in the midsummer season, new water is added every 1~2 days to keep the field water fresh. In addition, it is necessary to patrol the field three times a day to observe the activities and feeding of shrimps in the field. If any abnormal phenomenon is found, measures should be taken in time. In normal times, flood prevention, drainage and escape prevention work should be done well, and weather changes should be paid attention to at any time. Once there is a heavy rain, it is necessary to check whether the water inlet and outlet and shrimp interception equipment are intact in time to ensure safety to prevent shrimp from escaping.

5. The time for fishing shrimps raised in rice fields is generally when the rice is about to turn yellow and ripe, but there are also times when the rice is harvested, when the fields and ditches are filled with water and then raised for 1 to 2 months before being fished.

No matter when you fish, before you prepare to harvest and drain the water, you should first clear the field ditch so that the shrimp will flow slowly into the surrounding ditch with the field water. Then drain the water from the ditch and the shrimp will flow downstream with the water. You can use nets to fish and harvest at the drainage outlet. If you can't catch all the shrimp in one go, you can fill it with new water and repeat the fishing until all the shrimp are caught. During the harvest season, the temperature is generally high, so you can fish in the morning or evening to avoid damaging the shrimp. Before harvesting shrimp, you should prepare shrimp containers so that the adult shrimp can be transported to the market or transferred to another pond for temporary storage for sale.

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You can also read this article

"Strategies for the development of freshwater aquaculture of Penaeus vannamei in Tianjin"

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Hebei Fishery Services Registration Agency

Hengshui Fisheries Experiment Station

You can go here for consultation

Address: No. 149, Renmin West Road, Taocheng District, Hengshui City, Hebei Province

Postal code: 053000

Phone number: 2324985

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Hengshui Consumer Service Network

Here is an article, I hope it helps you

Freshwater Lobster Farming in Ponds

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That's all I can find for you, hope it can be useful~~

Because shrimp also have different varieties, and the genes of different varieties determine different colors.

Shrimp is an arthropod that lives in water. It belongs to the arthropod crustacean class and there are many species, including Antarctic red shrimp, green shrimp, river shrimp, grass shrimp, prawn, prawn, lobster, etc. Shrimp has high nutritional value and can be used as a traditional Chinese medicine.

Red shrimp: 50-90 mm in length, 1.5-9.0 g in weight, red in color, with the rear edge of the 1st to 6th abdominal segments being darker in color and bright red in ribbon shape, with a large cephalothorax that is easy to fall off. Origin and production season: Distributed in the East my country Sea, the southern Yellow Sea and the South China Sea, it is a dominant species in Zhejiang's offshore resources. It is the main catch in summer and autumn, especially in central and northern Zhejiang, where the yield is high.

Green shrimp: Green shrimp is one of the freshwater shrimps with high economic value. It grows fast, is large, reproduces quickly, has strong vitality, and is widely distributed in freshwater lakes in my country. Green shrimp meat is tender and delicious, rich in nutrition, and contains 16.40 grams of protein per 100 grams of edible part. Nutritionists believe that it has a certain brain-boosting function. After field investigation and expert evaluation by experts from the Provincial Ocean and Fisheries Bureau, Siyang, Jiangsu and Deqing, Zhejiang were rated as "Hometown of Green Shrimp".

River shrimp: River shrimp (also known as green shrimp, scientific name is Macrobranchium nipponense)) is widely distributed in my country's rivers, lakes, reservoirs and ponds. It is a high-quality freshwater shrimp.

Grass shrimp: Grass shrimp, scientific name Penaeus monodon, also known as black shell shrimp, belongs to the family Penaeidae. Because this shrimp likes to live in places with aquatic plants, it is called grass shrimp. Grass shrimp has the characteristics of fast growth, miscellaneous diet, wide salt tolerance, short breeding cycle, large size, delicious meat, rich nutrition, and high yield of adult shrimp.

Prawns: Prawns, also known as prawns, are one of the important seafood in my country. They are thick, delicious, and rich in protein. Chinese medicine believes that they are sweet, alkaline, and warm in nature, and can nourish the kidneys and strengthen yang, nourish yin, and strengthen the stomach.

Lobster: Lobster (scientific name: Palinuridae) is the general name for 19 species of lobsters in 4 genera of the family Hominididae, order Decapoda, Arthropoda. Also known as prawns, dragon head prawns, shrimp kings, sea shrimps, etc. It has a relatively large head and chest, a hard shell, colorful colors, a short abdomen, a body length generally between 20 and 40 cm, a weight of about 0.5 kg, and no claws. It is the largest type of shrimp. The heaviest can reach more than 5 kg, known as the lobster tiger. The body is thick and cylindrical, the back and abdomen are slightly flat, the head and chest carapace are well-developed, thick and spines, there is a pair of powerful supraorbital spines in the center of the front edge, and there is a closed gill chamber. It is mainly distributed in tropical waters and is a precious seafood. Eight species have been discovered in China, with the largest production of freshwater lobsters.

Jiwei shrimp: Jiwei shrimp refers to shrimp produced in the Jiwei area, which is a small river or creek near the coast. Fishermen bring in a lot of seawater from the river, and the seawater already contains sperm and eggs of shrimp. They are raised together and grow into Jiwei shrimp. They grow on the muddy bottom of the river and have a slightly dark body.

Sea shrimp: From the explanation of the sea shrimp, we know that the sea shrimp and the river shrimp belong to the same species. The only difference is that the sea shrimp grows in the sandy sea and has a red body. However, the taste of both is better, both are fresh and delicious.

Red rice shrimp: The price is relatively cheap, and the taste is also good when simply blanched. The characteristic is that the body is long and thin, with red spots on the body. There are two types: marine and farmed. Of course, the marine ones taste better. The shell is thin and easy to eat.

Bamboo shrimp: Also known as flower shrimp, bamboo shrimp, tiger shrimp, Japanese shrimp, and tiger shrimp. It is similar to tiger shrimp. It has long spines protruding forward on its head with fine serrations, and a thorn-like protrusion between its eyes. It has blue horizontal stripes, yellow appendages, and a bright yellow tail with blue. The shell is thin and hard, and the meat is thick.

Spring shrimp: Fishermen call it "white bean shrimp" or "pearl shrimp". Its characteristic is that its abdomen is full of eggs, some of which are red, purple, blue, etc. It is a product between salt water and fresh water. These shrimps can be found in the Yangtze River estuary in the mainland, Deep Bay in the northwest of Hong Kong's New Territories, and the Pearl River Estuary.

Mantis shrimp: The common mantis shrimp in Hong Kong are "Mantis scapula" and "Black Spot Mantis scapula", which can be simply divided into the former, which is the hard-shelled one that is often eaten, and the latter, which is the soft-bodied one with zebra stripes. They are produced in the "Fenliu Cape" area near Lantau Island in Hong Kong, adjacent to the bay and the Pearl River Estuary. However, many of them are now airlifted from Indonesia or Thailand. They are slightly dark in color, but of course they are less fierce than local products.

Mantis shrimp: There are many types of mantis shrimp on the market. The most common one is called cicada shrimp, also known as piglet shrimp. People in Hong Kong also call it thunder shrimp, and Taiwanese call it mantis shrimp. It looks fat and interesting. Its claws are thick and short, dark red, its forehead is flat and pentagonal, and its shell is hard and thick. The meat is fresh and delicious, and it is often used to make salad.

Because shrimp also have different varieties, and the genes of different varieties determine different colors.

Shrimp is an arthropod that lives in water. It belongs to the arthropod crustacean class and there are many species, including Antarctic red shrimp, green shrimp, river shrimp, grass shrimp, prawn, prawn, lobster, etc. Shrimp has high nutritional value and can be used as a traditional Chinese medicine.

Red shrimp: 50-90 mm in length, 1.5-9.0 g in weight, red in color, with the rear edge of the 1st to 6th abdominal segments being darker in color and bright red in ribbon shape, with a large cephalothorax that is easy to fall off. Origin and production season: Distributed in the East my country Sea, the southern Yellow Sea and the South China Sea, it is a dominant species in Zhejiang's offshore resources. It is the main catch in summer and autumn, especially in central and northern Zhejiang, where the yield is high.

The color of the shrimp's body is mainly determined by the pigment cells in the dermis of the shell. In the dermis of the shrimp's shell, there are various pigment cells, but most of them are blue-black, which is why the shrimp is blue. Among these pigment cells, there is a pigment called astaxanthin. Usually, it is mixed with other pigments and cannot show its bright red color. But after cooking, other pigments are destroyed and decomposed, but it is not afraid of high temperature, so the shrimp's shell shows the red color of astaxanthin. However, in the dermis of the shrimp's shell, the distribution of astaxanthin is uneven. Therefore, you will find that after the shrimp is cooked, it is not red all over. In places where astaxanthin is more distributed, such as the back part, it appears particularly red, while some shrimps where astaxanthin is less distributed will turn white as mentioned.