Which freshwater fish has been Wisconsin's official state fish since 1955?

The muskellunge has been Wisconsin's official state fish since 1955.

The muskellunge, commonly shortened to muskie, is a large member of the pike family, Esocidae. Its scientific name is Esox masquinongy. Wisconsin selected it as the state fish in 1955, reflecting the species' importance to the state's lakes, rivers, and recreational fishing culture.

Muskellunge are native to parts of North America, especially the Great Lakes, the upper Mississippi River basin, and connected inland waters. They are ambush predators with elongated bodies and sharp teeth. Their camouflage helps them wait near vegetation, woody cover, or other structures before striking prey.

Muskellunge are often confused with northern pike, a closely related species. The two can be distinguished by markings and by the number of sensory pores beneath the jaw. A muskie is also a different fish from the walleye, another famous Wisconsin game fish.