A New Sisorid Catfish of the Genus Exostoma Blyth from the Chindwin-Irrawaddy Drainage in Northeastern India (Teleostei: Siluriformes)

A new species of glyptosternine catfish of the genus Exostoma is described from the Chakpi River, a tributary of the Chindwin-Irrawaddy drainage in northeastern India. The new species can be distinguished from congeners of the Chindwin-Irrawaddy drainage except E. chaudhurii and E. vinciguerrae in having an adipose fin confluent (vs. separate) with the upper procurrent caudal-fin rays. It differs from E. chaudhurii in having anastomosing, rounded (vs. parallel) striae on the anterolateral surfaces of the lips and from E. vinciguerrae in having shorter adipose-fin base (29.1–32.3% SL vs. 35.4–39.4). This is the sixth species of Exostoma known from the Chindwin-Irrawaddy drainage.