Assessment of ichthyofaunal diversity of the suborder Cyprinoidei Fitzinger, 1832 (Actinopterygii: Cypriniformes) of western Indian Himalayan Region: present status and conservation - a systematic review

This review discusses the present status of freshwater fish families – Cyprinidae, Danionodae, and Xenocyprinidae of suborder Cyprinoidei and their conservation status, threats to the species diversity and the community-based conservation across the western Himalayan region. The family Cyprinidae, the largest among freshwater fish, consists of over 1,840 species; whereas Danionidae includes 375 species and Xenocyprinidae comprises around 173 species globally. A total of 35 genera and 76 species have been reported from various rivers and streams of four Indian Himalayan states. Of these, 67 species are classified as ‘Least Concern’, four as ‘Vulnerable’, two as ‘Near Threatened’, and one as ‘Endangered’ species as per the IUCN Red List. Uttarakhand exhibits the maximum species count (63) followed by Jammu & Kashmir (47), Ladakh (38), and Himachal Pradesh (36). The major threats faced by freshwater fish are damming, habitat fragmentation, pollution, invasive species, and climate change. Consequently, modern policies and community-led conservation initiatives play a vital role in preserving these freshwater ecosystems.