1. Around 1929, Japan introduced crayfish, and crayfish flowed to Nanjing, China via Japan.

2. Japan is the springboard for crayfish to enter East Asia. By the 1960s, crayfish were found in all places in Japan, including Hokkaido, except for some islands. Even the Japanese black crayfish, a Japanese relative of Procambarus clarkii, was almost wiped out by it.

3. In the early 1990s, crayfish quickly appeared on the dining tables of food stalls in Hubei, Anhui, and Jiangsu. The crayfish vendor was looking at the international market while his hands were cramping while counting money.

4. In order to adapt to the harsh living environment, crayfish have undergone strange evolution in China, mutating into new varieties such as spicy crayfish, fennel crayfish, and steamed crayfish.