Freshwater fish fauna of Hiranyakeshi River, the northern Western Ghats, India

The freshwater fish fauna of Hiranyakeshi River, a tributary of the Krishna River System, originating in the Western Ghats of Maharashtra, was studied for a period of three years from 2013–2016.  We reported 57 species belonging to seven orders, 17 families and 42 genera.  Cypriniformes was the most species rich order followed by Siluriformes, while Cyprinidae was the most predominant family.  At least 21 freshwater fish species found in Hiranyakeshi River are endemic to river systems originating from the Western Ghats, while nine species are endemic to the Krishna River system.  The true diversity of freshwater fishes in this region, however, is still obscure because of lack of detailed taxonomic studies in this region.  Of the total species, at least 11 are in the threatened and near threatened categories of the IUCN Red List and Hiranyakeshi River holds a good population of most of these species.  The fish fauna in this region, however, is threatened by several stressors including invasive fishing practices, water impediment due to upcoming dams, invasive introduced species and water pollution due to agricultural runoffs and industrial effluents.