The Mekong giant trout is the world record holder for the largest freshwater fish in terms of body weight, and a fishing team once caught a 646-pound (293-kilogram), 9-foot (2.7-meter) Mekong giant trout in the Mekong River basin in Thailand. The World Conservation Union (IUCN) classifies the fish as critically endangered, meaning they are one step away from extinction.

The Mekong Giant Tramp is the largest freshwater fish in the world, and in August 2007, a Mekong Giant Tramp was captured at Khone Falls on the Laos-Cambodia border.