Crayfish is listed in March, and May-September is its harvest month. The crayfish just listed are not too big, and most of them are concentrated in 4-8 yuan per crayfish. One or two or more crayfish below 3 yuan are rare. When a large number of crayfish are on the market in May, you will see very large crayfish. Crayfish can breed all year round, and the peak period is May-September. Crayfish are hermaphroditic and have significant secondary sexual characteristics. It can be distinguished from the shape of abdominal swimming limbs. The first abdominal swimming limb of male shrimp is specialized as mating thorn, and the first abdominal swimming limb of female shrimp is specialized as sperm hole. Secondly, there are obvious differences between the two pliers. The male pliers are thick, and there are bright red warts on the outside of both ends of the pliers, while the female pliers are small and the warts are not obvious. Thirdly, the claw feet of male shrimp are bigger than that of female shrimp, and the individual is bigger than that of female shrimp. Crayfish can mate almost all year round, but the peak is in spring every year. Mating is generally carried out in the open area of water, and the mating temperature is between 65438 05℃ and 365438 0℃. During mating, the male shrimp injects sperm into the seminal vesicle of the female crab (shrimp) through mating spines, and the sperm can still fertilize the egg after being stored in the seminal vesicle for 2-8 months. After mating, female shrimps dig holes one after another, and when the eggs mature, they complete the process of ovulation, fertilization and larval development in the holes. Extended information: 20 19 The first wave of crayfish was listed in the farmer's market one month in advance, and it is hard to find a crayfish. On March 16, the restaurant and hotel were listed in advance at 6 pm. Walking into the dining hall of Huanglong Hotel, I saw the fiery crayfish area at a glance. Compared with other areas, the crayfish area is the most popular, with delicious food. Zhou Bo, the catering manager of Huanglong Hotel, said that the crayfish in the canteen mainly came from Jiangsu, and the "Lobster Club" was launched at this time in previous years, but this year's "opening" time was one month earlier than last year. In fact, more "anxious" than hotels are some restaurants that focus on crayfish. "Lobster restaurants like ours follow the season, usually open at the end of March, gather guests in April and enter the peak season in May. The owner of a snack bar in Shengli River Food Street started to choose shrimps at the base just after the 15th day of the first month. At the end of February, old customers took the lead in eating crayfish. The reporter visited and found that crayfish had already climbed onto the table in the nightingale gathering places such as Hedong Road and Shengli River Food Street. But it is still difficult to find them in the farmer's market where Ma Sao likes to go. Sister Li, who is engaged in aquatic products business in Zhonghe Farmers' Market, said that crayfish will not be listed until Qingming. "Now the price is expensive, and the purchase price is fifty or sixty yuan a catty. Few people buy, and buying is risky. Reuters, a crayfish farmer in Jiangsu, revealed that the crayfish on the market now come from Guizhou and Yunnan where the climate is warm, or from last year's shrimp sinking or greenhouse farming. No matter which cost is high, the purchase price of crayfish is also expensive now. " This year's crayfish and shrimp seedlings have just come on the market. According to the normal growth trajectory, they will be listed in large quantities after Qingming at the earliest, which is cheap and delicious. "