Boramy, netted last week off Koh Preah, an island along the northern Cambodian stretch of the river, took the record from a 293 kg giant catfish that was caught upstream in northern Thailand in 2005.
The Mekong has the third-most diverse fish population in the world, according to its River Commission, though overfishing, pollution, saltwater intrusion and sediment depletion have caused stocks to plummet.
