Troglocyclocheilus khammouanensis, a new genus and species of cave fish from the Khammouan karst, Laos (Teleostei : Cyprinidae)

Troglocyclocheilus khammouanensis, new genus, new species, is distinguished by the absence of externally visible eyes, the presence of several rows of sensory papillae on the head, the shape of the mouth, lips and rostral fol d, the slender and smooth last simple dorsal ray, and the lateral line scal es with a notch on the posterior margin. Other southeast and east Asian cav e cyprinids are discussed. The sensory function of the 'parietal processes' or 'parietal organs' of some species of Sinocyclocheilus land its synonym Gibbibarbus) is doubted and an hydrodynamic function is hypothesized instea d. The publication dates and authorship of S. hyalinus, Protocobitis and P. typhlops are discussed and lectotypes are designated for S. hyalinus and P . typhlops. Barbus speleops from Tham Phu Khieo, Thailand, belongs to the g enus Poropuntius (nov. comb.).