Exostoma hajiensis, a New Sisorid Catfish, (Teleostei: Sisoridae) from Arunachal Pradesh, North-Eastern India

A new sisorid catfish, Exostoma hajiensis, is described from a small distributary of Subansiri River of Brahmaputra River basin in Arunachal Pradesh with five specimens. It is distinguished from its close congeners in Brahmaputra river basin in having a combination of the following characters: posterior extremity of adipose fin base distinctly angular with sharply pointed dorsoposterior margin; presence of both parallel and rounded striae on the anterolateral surfaces of the lips; predorsal length (41.5–44.9 % SL); pelvic fin length (15.9-16.7 % SL);preanal length (75.8−78.1% SL); adipose fin base length (23.1-26.7% SL); dorsal-adipose distance (10.2-17.1% SL) and caudal peduncle (15.4-19.6 % SL).