[[Akysis]]

Members of the akysid catfish genus Akysis are small catfishes with tuberculate skin and a color pattern generally consisting of yellow patches or bands on a brown body. They are diagnosed by the anterior margin of the pectoral spine with a notch visible dorsally and the nasals with expansions beyond the canal-bearing region (de Pinna, 1996), and are found in fast-flowing streams and rivers in Southeast Asia [more specifically in the area bordered by the Irrawaddy River drainage to the west, the Barito River drainage to the east, the Lancanjiang (upper Mekong) drainage to the north and the Citarum River drainage to the south]. There is considerable hidden diversity within the genus; more than half of the 29 valid species have been described within the last decade (Ng, 1996; Ng & Kottelat, 1996; 1998; 2000; 2004; Ng & Tan, 1999; Ng & Freyhof, 2003; Ng & Rainboth, 2005; Ng & Sabaj, 2005).

Recently, specimens of Akysis collected from the Sittang River drainage in Myanmar were made available to me. This material was initially identified as Akysis pictus Günther, 1883 from southern Myanmar, but close examination revealed enough differences to warrant its recognition as a distinct species. The description of this new species as Akysis longifilis forms the basis of this study.