Mahi-mahi

The Mahi-Mahi (pronounced ɑː|h|iː|ˈ|m|ɑː|h|i, "ma-hee-'-ma-hee") is a fish, introduced in. The player can only fish for it at the pier.

Donating to the Museum
As with all fish in the Animal Crossing series, the Mahi-Mahi can be donated to the museum, followed by a small talk by Blathers about it.

In New Horizons

 * The mahi-mahi is an ocean fish known for its wide, somewhat-cute face. It can reach over six feet long. It is known by many different names including "dolphinfish," even though it has no relation to dolphins. They live only in warm, tropical waters...which perhaps explains the relaxed, happy look on their faces.

Further information
Mahi-Mahi, also referred to as the common dolphinfish is a surface-dwelling ray-finned fish found in off-shore temperate, tropical, and subtropical waters worldwide. It is one of two members of the family Coryphaenidae, alongside the pompano dolphinfish. These fish are most commonly found in the waters around the Gulf of Mexico, Costa Rica, and Hawaii.