Hypsibarbus wetmorei, the golden belly barb, lemon fin barb, lemon barb or Kerai is a species of cyprinid fish. It is native to the Mae Klong, Mekong, Chao Phraya, Tapi and Pahang rivers in Mainland Southeast Asia. Although locally common and considered to be a species of Least Concern, it is threatened by overfishing, dams and pollution. It typically reaches 25 cm (10 in) in length, but has been recorded up to about 70 cm.