Leafhoppers are one of the largest families of plant-feeding insects. There are more leafhopper species worldwide than all species of birds, mammals, reptiles, and amphibians combined. Leafhoppers feed by sucking the sap of vascular plants, and are found almost anywhere such plants occur, from tropical rainforests, to arctic tundra. Several leafhopper species are important agricultural pests.
Source: University of Illinois at Urbana-Champaign