Mahi-Mahi, also known as Dorado or the confusing alternative “Dolphin fish,” is a fast-swimming predatory fish found in tropical and subtropical waters globally. Despite confusion, this species is not a shark. Taxonomic differences place Mahi-Mahi and sharks in entirely separate biological classes. This ray-finned creature is a popular item in global cuisine, but its various names often lead to questions about its true nature.
The True Identity of Mahi-Mahi
The Mahi-Mahi holds the scientific name Coryphaena hippurus, classifying it as a ray-finned bony fish. It belongs to the family Coryphaenidae, which contains only two species of dolphinfish. The Hawaiian name “Mahi-Mahi” translates to “very strong,” accurately describing this muscular, surface-dwelling predator.
The use of “Dolphin fish” is a historical source of confusion, often linking it to the marine mammal dolphin. To avoid this misconception, Mahi-Mahi became the preferred commercial name globally. In Spanish-speaking regions, it is called Dorado, referring to the vibrant, shimmering golden color it exhibits when freshly caught. Mahi-Mahi are known for their striking iridescent colors and the distinct, blunt forehead that develops on mature males.
Distinguishing Bony Fish from Cartilaginous Fish
Mahi-Mahi is a member of the class Osteichthyes, or bony fish, a group fundamentally distinct from sharks, which belong to the class Chondrichthyes, or cartilaginous fish. The most apparent difference is in the skeletal structure; Mahi-Mahi possess an endoskeleton made entirely of hard, calcium-rich bone. Sharks, in contrast, have a flexible, lighter skeleton composed primarily of cartilage.
Bony fish like the Mahi-Mahi have a rigid, protective bony flap called an operculum that covers their gills. Sharks lack this cover, instead having exposed gill slits on the sides of their heads. Furthermore, the skin of a Mahi-Mahi is covered in smooth, overlapping scales, while a shark’s skin is covered in tiny, tooth-like structures called placoid scales, giving it a rough, sandpaper-like texture.
Mahi-Mahi as a Seafood Choice
Once the confusion about its identity is cleared, Mahi-Mahi is appreciated as a desirable seafood option globally. It is prized for its firm texture and mild, sweet flavor, making it versatile for grilling, baking, or searing. Its popularity is also supported by its rapid growth and relatively short lifespan.
The quick growth cycle of Mahi-Mahi means that it generally does not bioaccumulate mercury to the same extent as much larger, longer-lived apex predators, such as some shark species. However, it is classified by some health organizations as having moderate concentrations of mercury. Therefore, vulnerable groups like pregnant or nursing mothers and young children are often advised to limit their consumption to moderate levels, such as once per week.