'' The Cicadellidae combine the following features: • The thickened part of the
antennae is very short and ends with a
bristle (arista). • Two
ocelli (simple eyes) are present on the top or front of the head. • The
tarsi are made of three segments. • The femora are at front with, at most, weak
spines. • The hind tibiae have one or more distinct keels, with a row of movable spines on each, sometimes on enlarged bases. • The base of the middle legs is close together where they originate under the
thorax. • The front wings not particularly thickened. An additional and unique character of leafhoppers is the production of
brochosomes, which are thought to protect the animals, and particularly their egg
clutches, from predation as well as pathogens. of an unidentified
Typhlocybinae species Like other
Exopterygota, the leafhoppers undergo direct development from
nymph to adult without a
pupal stage. While many leafhoppers are drab little insects as is typical for the
Membracoidea, the adults and nymphs of some
species are quite colorful. Some – in particular hoppers in the tribe
Stegelytrini – have largely translucent wings and resemble
flies at a casual glance. Leafhoppers have
piercing-sucking mouthparts, enabling them to feed on
plant sap. A leafhoppers' diet commonly consists of sap from a wide and diverse range of plants, but some are more
host-specific. Leafhoppers mainly are
herbivores, but some are known to eat smaller insects, such as
aphids, on occasion. A few species are known to be
mud-puddling, but as it seems, females rarely engage in such behavior. Many species are also known to opportunistically pierce the human skin and draw blood but the function of such behaviour is unclear. Leafhoppers are
micropredators that can act as
vectors transmitting
plant pathogens, such as
viruses,
phytoplasmas and bacteria. Cicadellidae species that are significant agricultural pests include the
beet leafhopper (
Circulifer tenellus), the maize leafhopper (
Cicadulina mbila), potato leafhopper (
Empoasca fabae), two-spotted leafhopper (
Sophonia rufofascia),
blue-green sharpshooter (
Graphocephala atropunctata),
glassy-winged sharpshooter (
Homalodisca vitripennis), the
common brown leafhopper (
Orosius orientalis), rice green leafhoppers (
Nephotettix spp.), and the white apple leafhopper (
Typhlocyba pomaria). The
beet leafhopper (
Circulifer tenellus) can transmit the beet curly top virus to various members of the
nightshade family, including tobacco, tomato, or eggplant, and is a serious vector of the disease in
chili pepper in the Southwestern United States. In some cases, the plant pathogens distributed by leafhoppers are also
pathogens of the insects themselves, and can
replicate within the leafhoppers'
salivary glands. Leafhoppers are also susceptible to various insect pathogens, including
Dicistroviridae viruses, bacteria and
fungi; numerous
parasitoids attack the eggs and the adults provide food for small
insectivores. Some species such as the Australian
Kahaono montana even build silk nests under the leaves of trees they live in, to protect them from predators. ==Systematics==