Which spanish conqueror is not accurately matched with the area he explored or conquered?

Ponce de León - was a Spanish explorer and conquistador. He became the first Governor of Puerto Rico by appointment of the Spanish crown. He led the first European expedition to Florida, which he named. He is associated with the legend of the Fountain of Youth, reputed to be in Florida.
Hernando de Soto was a Spanish explorer and conquistador who led the first European expedition deep into the territory of the modern-day United States, and the first documented European to have crossed the Mississippi River.