Abstract
Akysis bilustris, new species, is described from the Xe Kong drainage (a subdrainage of the Mekong River) in southern Laos. It is distinguished from congeners in having a unique combination of the following characters: eye diameter 14.0– 17.5% HL, serrae on posterior margin of pectoral spine 2–3 and longer than half width of spine, pectoral fin reaching to or overlapping pelvic-fin base (length 24.5–29.3% SL), adipose-fin base length 14.3–18.3% SL, body depth at anus 11.4– 13.8% SL, caudal-peduncle length 19.6–23.4% SL, caudal-peduncle depth 6.7–9.2% SL, caudal fin emarginate, and vertebrae 30–31.References
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