Which body of water was named after a Spanish conquistador in the Americas?

It was "Francisco de Ulloa" who in 1539 named the Sea of Cortez (Cortes) after "Hernan Cortes" - a Spanish conquistador. It was first thought that this waterway was a mythical strait called Anian, which was supposed to lead from the Pacific to the Atlantic. It turned out to be just a sea. Francisco himself was a conquistador and explorer, and just named this new body of water to honor his respected comrade. "Hernan Cortes", died in 1547, and was well known and revered for being the conqueror of Mexico and the fall of the Aztect Empire.

The Sea of Cortez (Cortes) is also known as The Gulf of California. It is located between Northwest Mexico and the East side of the Baja peninsula; starting its way from California and ending in the Pacific Ocean. It is 1,126 km (700 mi) long and 48–241 km (30–150 mi) wide, with an area of 177,000 km2 (68,000 sq mi), a mean depth of 818.08 m (2,684.0 ft), and a volume of 145,000 km3 (35,000 cu mi).