Thryssocypris smaragdinus is a species of cyprinid of the genus Thryssocypris.[1] It inhabits western Borneo in Indonesia. It has not been evaluated on the IUCN Red List, was described in 1984 and is considered harmless to humans. Its maximum length among unsexed males is 5.4cm (02.1inches). It has 9 to 10 dorsal soft rays, 12 to 14 anal soft rays and 38 to 39 vertebrae.