Kryptopterus geminus is a species of catfish belonging to the family Siluridae. It can be distinguished from all its congeners, with the exception of Kryptopterus cryptopterus, by the almost flat dorsal profile with no concavity behind the head. This species grows to a length of 17.1 centimetres (6.7 in) SL.Examples of this distinctively shaped, translucent fish used to be assigned to the long-established species K.