A planthopper is any insect in the infraorder Fulgoromorpha within the Hemiptera. The name comes from their remarkable resemblance to leaves and other plants of their environment and from the fact that they often "hop" for quick transportation in a similar way to that ofgrasshoppers. However, these planthoppers generally walk very slowly so as not to attract attention. Distributed worldwide, all members of this group are plant-feeders, though surprisingly few are considered pests. The infraorder contains only a single superfamily, Fulgoroidea. Fulgoroids are most reliably distinguished from the other members of the classical "Homoptera" by two features; the bifurcate ("Y"-shaped) anal vein in the forewing, and the thickened, three-segmented antennae, with a generally round or egg-shaped second segment (pedicel) that bears a fine filamentous arista.
Nymphs of many Fulgoroids produce wax from special glands on the abdominal terga and other parts of the body. These are hydrophobic and help conceal the insects. Adult females of many families also produce wax which may be used to protect eggs.
Planthoppers are often vectors for plant diseases, especially phytoplasmas which live in the phloem of plants and can be transmitted by planthoppers when feeding.