Found in the Chao Phraya and Mekong basins (Ref. 26336, 33488); also from Bangkok, Chanthaburi, Nakhon Sawan and Phra Nakhon Si Ayutthaya (Ref. 37773). From Xayabouri in Laos to Chiang Saen in Thailand, it undertakes upstream migrations from March to August. From Klong Kaem District, Ubolratchatani, fish migrates upstream in February; at Khemmaratch further upstream in Ubolratchatani, it moves upstream in March-April; at Mukdahan, it goes upstream in May. However, it migrates downstream at Klong Kaem in June-July (Ref. 37770). Fish caught in dams are known to reach up to 15 kg in (Jean-Francois, pers. comm. 11/02). Also Ref. 12041, 26336, 27732, 37772, 43281.