Fishes of the Xe Kong drainage in Laos
The fishes of the Xe Kaman drainage in Laos have been surveyed between 15 and 24 May 2011.
Fourty-five fish species were observed, bringing to 175 the number of species recorded from the Xe Kong drainage in Laos, 9 of them new records for the drainage. Twenty-five species (14 %) have been observed from no other drainage and are potentially endemic to the Xe Kong drainage.
Five species observed during the survey are new to science (unnamed); they belong to the genera Scaphiodonichthys, Annamia, Sewellia and Schistura (2 species). Three of them have been discovered during the survey, the others although still unnamed were already known for some time, under an erroneous name. In the Xekong drainage, a total of 19 (11 %) fish species are still unnamed or their identity is not yet cleared and they are potentially also new to science.
The survey focused on Dakchung district. Eleven species were collected on Dakchung plateau and 3 are apparently new to science (and thus 27 % of the fish fauna of the plateau is endemic there). Most of the endemic species (and all the new species discovered by the survey) are from rapids and other high gradient habitats. This reflects the limited distribution range of rheophilic species, but may also partly result from a sampling bias.