Snails and shark fin, dried scallops, abalone side by side to become the world's four famous dishes, French snails, garden snails and onyx snails are many Chinese food favorites, but in front of this giant snail, foodies can not be crazy.
At the onset of the rainy season, a super-sized snail appears in the streets of some southern cities, this kind of oversized snail is generally 7-8 cm, the largest can grow to more than 20 cm, is a medium-sized land snail. Don't show kindness to it, or it will unceremoniously make a mask for your face.
This snail is called the African large snail, also known as the brown cloud agate snail, belongs to the agate snail genus of the agate snail family, the shell is slightly spindle-shaped, and it is more pointed and thin compared with the common native snail, but it is more similar to some field snails. The shell texture of the African large snail is thick, the thread is generally about six or seven layers, the shell surface is white or yellow, and there are tan longitudinal stripes or cloud-like stripes perpendicular to the thread.
The shell of the African giant snail is directly opened - when hibernating, or when the climate is too dry, they can only use the secreted white mucus to make a white film (false mouth cover), leaving only a small hole to breathe, and the snail is shrunk into the shell to prevent dehydration, which plays a certain protective role.
As can be seen from the name, it is not a domestic animal, its home was originally in East Africa, Africa, and is known as the most successful invasive species in the world.
Because its invasion routes are really extensive, in addition to being able to pass through ships, trains, cars, planes and other means of transport, it can also follow the spread of ornamental plants, seedlings, plates, containers, and cargo packaging boxes. Some foodies who like to eat snails will also become accomplices in their invasion without understanding their true face.
The African Big Snail went out of the African route
The reason for this situation is that for food-poor Africa, this oversized snail can be said to be a super delicious, and rich in protein, in the African market, you can often see locals with buckets to pile snails together to sell, they sell goods in a very primitive way, generally sold by one or on a pile.
Seeing that this large snail is so popular in Africa, some foodies and merchants will think that these large snails are no different from French snails, especially the French baked snail is a world famous dish, so they want to take these snails home or tap the commercial value of these African snails.
In addition to foodies, some people who like to keep pets also have to carry this pot, when an American child brought back three large snails to Miami, and their number increased from 3 to 18,000 in just 7 years.
Florida spent more than a million dollars to annihilate this invasive species in 10 years. As a result, by 2011, they were making a comeback again, and it was not known when they would be able to cut down the grass and remove the roots.
The time of the invasion of this large snail in China can be traced back to 1931, they landed from Xiamen, relying on strong fertility, rapidly spread throughout the country, this large snail can lay eggs 4 times a year, each time laying 150-300 eggs. After the eggs hatch, after 5 months of sexual development and maturity, China's Fujian, Taiwan, Guangdong, Guangxi, Yunnan, Hainan and other places have also become their world.
China has always had a very high degree of digestion of many invasive species, whether it is the introduction of bullfrogs or tilapia, snakehead fish, mussels, etc., under the cooking of Chinese chefs, it has become a common Chinese cuisine and is sought after by Chinese foodies.
However, in the 80 years of invasion of China, the African giant snail did not harvest the same treatment as the invasive species of tilapia from Africa, nor did it replace the table status of the French snail, and the Chinese chef who was good at turning decay into magic did not develop any new dishes for it, but became a street rat, and everyone shouted and beat.
Why can't Chinese foodies conquer the African snail? As an invasive species, the African giant snail has fully and clearly identified its own position, can eat and live. Just like I just said, each spawn of 150-300 eggs, and 4 eggs are laid a year, so that a large African snail can produce thousands of small snails in a year, which is creepy. If they invade a new environment with few predators, in this "perfect snail nest", it will usher in an explosive growth that is a great threat to the local ecology.
And they are hermaphrodites (allogeneic mating). So even if the action is slow, as long as two snails meet, they can reproduce.
So who will be the male and who will be the mother? In nature, all living things except humans want their genes to survive, and the female spends more energy on reproduction, so if the two snails rely solely on negotiation, it is difficult for one party to compromise and accept the identity of the female.
Since it cannot be discussed, it can only rely on force.
In order to gain an active position, they will shoot a dark weapon called "love dart" at each other during the duel.
In China, it is precisely because of underestimating the reproductive ability of African large snails and overestimating the combat effectiveness of Chinese foodies that they tried to introduce African large snails for breeding, but on the one hand, there was an oversupply, on the other hand, there was a lack of effective breeding control and environmental isolation, and these big guys successfully leapt over the farm, escaped to natural habitats, and established their own populations.
They are even more unambiguous when it comes to eating. Extremely destructive, like locusts, all kinds of plants, trees in the field, delicious and unpalatable, can not eat, all swept away, it is said that the cement on the ground are all chewed, the white slime on the ground, into the nightmare of many southerners.
As an invasive species. They have become worldwide agricultural pests, harming more than 500 crops in hot and humid regions such as Asia, the Pacific, the Indian Ocean and the Americas.
African large snails do not touch directly with their hands, especially small children with weak immunity, African large snails have a lot of mucus, there are many unknown bacteria in the mucus, if the body's resistance to bacteria is weak, it is easy to cause allergic reactions.
It is also a carrier of many germs and pathogens, such as the Angiostrongylus cantonensis,d'êtrex, which uses the African giant snail as an intermediate host. By eating African large snails infected with this parasite, or by contact with their excrement, the nematode may enter the human body, parasitize the human central nervous system or cerebrospinal fluid, and even cause fatal meningitis.
In Guangzhou, the infection rate of Guangzhou tube roundworm in African large snails is 27.3%, and the infection rate is 72 per snail; in Shenzhen, there are hundreds of parasites in 1 African large snail.
The parasites of African large snails include: Esoteric cat roundworm, Guangzhou tube strongiae, vertebral roundworm, schistosomiasis, murine lung nematode, which can cause tuberculosis in addition to meningitis. In addition, the vegetables and fruits that the African snail crawls over may remain pathogens, and these pathogens can also invade the thin tender places or breaks of human skin, causing infection.
Eating African large snails has a certain danger, which is also the reason why Chinese foodies are crazy, at present, it is one of the first 16 invasive alien species in China, listed in the "List of Invasive Alien Species in China". It is extremely harmful to vegetables and other crops, and is a class II quarantine pest for the entry and exit of China.
If you encounter this kind of large snail in the wild, don't play with it as a pet, don't cook it to eat, do a good job of cleaning and hygiene, and can be killed with alkaline items such as quicklime or grass ash.