The black shrimps priced at 20 yuan per pound are black tiger shrimps.

Black tiger shrimp, also known as black shrimp and black tiger shrimp, is a common freshwater shrimp. Its body color is black or dark brown, and its appearance is similar to other shrimps, but it is larger in size, usually around 10-15 cm in size. Black tiger shrimp has delicious meat and delicate taste, and is loved by many people. In the market, the price of black tiger shrimp is usually higher, usually around 20 yuan per pound.