Leafhopper diversity blueprint along the elevation gradient of North-Western Himalayas, India.

Abstract

Species richness pattern along the elevation gradient forms precious tools in understanding diversity gradients and their principal mechanisms. Himachal Pradesh, one of the hubs of biological diversity has congenial atmospheric conditions and is homeland for large number of insects. Despite being one of the major biodiversity hotspots several insect families remain poorly studied in the state including, Cicadellidae: Hemiptera. A total of 85 leafhoppers species belonging to 61 genera of 12 subfamilies of Cicadellidae were recorded from all the 12 districts of the state covering 25 locations. Four species, Gurawa monorcephala Pruthi, Leofa pulchellus Distant, Olidiana kirkaldyi (Walker) and Paralimnellus cingulatus (Dlabola) appeared to be new records from Himachal Pradesh and one species, Pseudosubhimalus sp. Nov was new from India. Species richness as well as diversity increased with rising altitude from Sub-mountain low hills zone I (350-650m amsl) with a hump at mid hills zone II (651-1800m amsl) following a declining trend towards high hills wet temperate zone III (1801-2200m amsl) and high hills dry temperate zone IV (above 2200m amsl). This elevational disparity in species richness might be due to variations in the physiological requirements, host preference and changing climate. Abundance of leafhopper species as observed in temperate regions is of serious concern of global warming, due to their job in transmission of plant viruses and phytoplasmas, of which the world has still no control, therefore the future of food security lies in the paradigm of uncertainty.