Tuna: Tuna is 44 1- 1720mm long and weighs 2000-92000g.

Spanish mackerel: Spanish mackerel is 50- 1000mm long and weighs 300- 1000mg.

Second, different body types.

Tuna: Tuna has a slightly flat body and a slender tail.

Spanish mackerel: Spanish mackerel has a long flat body and a thin tail handle.

Third, the colors are different.

Tuna: Tuna has a blue back and a silver belly.

Spanish mackerel: Spanish mackerel has dark stripes or black and blue spots on its back.

Fourth, the distribution is different.

Tuna: Tuna is mainly distributed in the sea near the equator.

Spanish mackerel: Spanish mackerel is mainly distributed in the northwest Pacific Ocean.

Baidu encyclopedia-tuna

Baidu encyclopedia-Spanish mackerel