Anchovy is a kind of fish that lives in fresh water environment, mainly distributed in major river basins and lakes in China. Although some anchovies can also live in salt water environment, they are usually classified as freshwater fish. This is because the physiological and behavioral characteristics of anchovies in fresh water are more in line with the characteristics of freshwater fish, such as gill structure and eating habits adapted to fresh water environment. Therefore, anchovies are usually classified as freshwater fish.