ca. 4000 described spp. in our area, with perhaps half that many yet undescribed (Dr Hamilton's ballpark estimate); 1500 spp. known from Canada(1)
Active insects, good fliers or jumpers. 3 segmented tarsi. Antennae very short and bristlelike. Cicadas are relatively large with membranous wings. Hoppers are small to minute with thickened front wings, usually.
"The most striking characters separating the Cicadomorpha from the Fulgoromorpha are the proportions or parts of the head. In most Cicadomorpha (except those with an extremely elongated head), the clypeus occupies the largest portion of the face, and in the Cicadoidea and Cercopoidea even reaches the crown (head dorsum). In the Fulgoromorpha, the clypeus is small and restricted to the lower half (or less) of the face. The antennae of the Cicadomorpha are segmented (in Cicadoidea and nymphs of Cercopoidea and Myerslopiidae) or distally annulated (when segments of flagellum are fused), but lack the bulbous basal segments seen in Fulgoromorpha. Tegulae are universally absent in the Cicadomorpha. Wing polymorphism is present in many Cicadellidae, both sexual and host related, but wing polymorphism is otherwise rare in the Cicadomorpha." — Bartlett et al. 2018
Online keys provided in (2)
worldwide; for ranges of various taxa, see(2)(3)(4)
Most leafhoppers and planthoppers feed on green plants and many show extreme host specificity.(5)
Many nymphs in Fulgoroidea feed on fungi and some spend their entire lives in caves. Some hoppers are subterranean and feed on plant roots and others potentially do not eat as adults and survive off of fat reserves.
Despite the name, not all members of this group hop (e.g. cicadas).