Both Eriocheir sinensis and Portunus trituberculatus belong to the genus Portunus, but their morphology is quite different. The head breastplate of Eriocheir sinensis is gray moire, and the unevenness is not obvious, while the head breastplate of Portunus trituberculatus is cyan or ochre, and the surface is covered with fine particles.

2. Different living environment

Portunus usually lives and breeds on the seabed of 3-5 meters, migrates to the deep sea of 10-30 meters in winter, and likes to make holes at the bottom of sediments.

Its adaptive salinity is 16 ‰-35 ‰, water temperature is 4℃-34℃, PH value is 7-9, optimum salinity is 26 ‰-32 ‰, and optimum temperature is 22℃-28℃. Water quality requires fresh and high dissolved oxygen. When the environment is not suitable or the shelling is not complete, there is a phenomenon of self-cutting, and the feet can be regenerated after being cut off.

3. Different distribution

Flower crabs are mainly distributed in coastal areas such as Zhejiang, Fujian, Taiwan Province, Guangdong, Guangxi and Hainan Island.

Portunus is mainly distributed in Liaoning, Hebei, Tianjin, Shandong, Jiangsu, Zhejiang, Fujian and other nearby waters in China.