Thryssocypris tonlesapensis is a species of cyprinid of the genus Thryssocypris, described in 1984.[1] It has a maximum length of 6.4cm (02.5inches) among unsexed males and is endemic to the Mekong basin, inhabiting Cambodia and Laos.[2] It has 9-10 dorsal soft rays, 15-16 anal soft rays and 43-44 vertebrae. It is considered harmless to humans and is classified as "least concern" on the IUCN Red List.