1, different shapes
Catfish with big mouth: long body and flat back; Wide and flat head; Very wide between eyes; The mouth is inferior and arc-shaped; The jaw has villous teeth, which must be 4 pairs, and the mouth angle must exceed the branchial hole. There are auxiliary respiratory organs in the gill cavity; The dorsal and gluteal fins are both long and not connected with the caudal fin; The pectoral fin has hard spines; The caudal fin is round.
Catfish:
Silurus asotus:
Silurus asotus: long body and flat back. Flat head. The mouth is big, and the end of the mouth crack stops below the front edge. The mandible is prominent, and the upper and lower jaws have fine teeth. Adult fish must reach the end of pectoral fin in 2 pairs 1 award. The front edge of pectoral fin thorn has obvious serrations. The base of gluteal fin is very long and there are many fins. The caudal fin is small, slightly concave, and the upper and lower leaves are the same length. There are long beards on both cheeks.
2. Different living habits
Silurus meridionalis belongs to the bottom fish, which mostly lurks in groups at the bottom of the pool during the day and spreads out at night. Silurus meridionalis is docile, not good at jumping, not drilling mud, and easy to catch.
Silurus asotus: It mainly lives in the middle and lower layers of rivers, lakes, reservoirs and pits, mostly in coastal areas, mostly hiding in grass, rocks or deep water during the day, and frequently foraging at night. After autumn, living in deep-water activated sludge overwinters, and the feeding degree is also weakened.
3. Different eating habits
Silurus meridionalis is a carnivorous fish, which mainly eats fish, shrimp, aquatic insects, benthos and so on, and can eat fish equivalent to one third of its own body length. Under the condition of artificial feeding, we also eat animal offal and leftovers from livestock and poultry processing, such as chicken intestines and pig lungs.
Silurus asotus: sexually inactive, living in seclusion in water grass or caves during the day, going out for food at dusk and at night, feeding on small fish and shrimp.
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