A stingray weighing close to 900 pounds? This 6.6-ft.-wide giant stingray was caught, measured and released in Thailand this week, part of a National Geographic scientific expedition to search for giant fish. It may well be the largest known freshwater fish in the world.

University of Nevada biologist Zeb Hogan, a National Geographic Emerging Explorer, was pleased to discover healthy populations of giant stingray in Thailand, where once the fish were considered critically endangered.