1. Barracuda has a small head, four pairs of tentacles, smooth and scaleless body surface, irregular spots in body color, ivory belly color and small tail tip; Catfish has a big flat head, a wide mouth and rich mucus on its body surface. There are four beards on the upper and lower jaws, and there are no scales. The back is black and blue, and the abdomen is white or light gray.

2. Barracuda mainly swims in the middle and lower water, likes to swim vertically from beginning to end, and has more activities during the day; Catfish mainly live in the middle and lower layers of rivers, lakes and other waters, hiding in grass, rocks or deep water during the day and foraging frequently at night. Barracuda is native to freshwater lakes and rivers in North America, and mainly distributed in the Yangtze River and Yellow River basins in China. Catfish are mainly distributed in rivers, lakes and reservoirs in the Yangtze River Basin and Heilongjiang Basin.