1. Differences in family and genus: As mentioned above, the mackerel and Spanish mackerel belong to the same order and class, but the family and genus to which they belong are different. Specifically, mackerel belongs to the mackerel family Mackerel, while Spanish mackerel belongs to the Spanish mackerel family Mackerel. The mackerel belongs to the mackerel family, while the Spanish mackerel belongs to the horse mackerel family.

2, body shape difference: mackerel and Spanish mackerel have differences in body shape. The body shape of the mackerel is thicker and flatter, while the body shape of the Spanish mackerel is longer and flatter.

3. Body shape: The body shapes of mackerel and Spanish mackerel are also different. The length of the body of the mackerel as an adult ranges from 20-40 centimeters, and its weight ranges from 150-400 grams. The adult Spanish mackerel, on the other hand, has a body length range of 25-50 centimeters and a weight of 300-1000 grams. As you can see, the Spanish mackerel is relatively larger than the mackerel.

4. Different distribution ranges: mackerel and Spanish mackerel both live in the ocean, but there are some differences in their distribution areas. The mackerel is found in the western part of the Pacific Ocean, while the Spanish mackerel is found in the western part of the North Pacific Ocean, which is a relatively small area.

5. The economic value is different: mackerel and Spanish mackerel are both economically valuable, and mackerel has a higher economic value than mackerel.