Spittle bug/froghopper
[昆]沫蝉,吹沫虫
small leaping herbivorous insect that lives in a mass of protective froth which it and its larvae secrete
The froghoppers, or the superfamily Cercopoidea, are a group of Hemipteran insects, in the suborder Auchenorrhyncha. Traditionally, most of this superfamily was considered a single family, Cercopidae, but this family has been split into three separate families for many years now: the Aphrophoridae, Cercopidae, and Clastopteridae. More recently, the family Epipygidae has been removed from the Aphrophoridae. These families are best known for the nymph stage, which produces a cover of frothed-up plant sap resembling spit; the nymphs are therefore commonly known as spittlebugs, or spit bugs, and their froth as cuckoo spit or snake spit. The final family in the group, Machaerotidae, is known as the tube spittlebugs because the nymphs live in calcareous tubes, rather than producing froth as in the other families.
Nymphal form of spittlebug encased in foam for protection and moisture.
The froth serves a number of purposes. It hides the nymph from the view of predators and parasites, it insulates against heat and cold, thus providing thermal control and also moisture control. Without the froth the bug would quickly dry up. The nymphs pierce plants and suck sap causing damage, and much of the excess filtered fluids go into the production of the froth. A few species are serious agricultural pests.
Adult froghoppers jump from plant to plant; some species can jump up to 70 cm vertically: a more impressive performance relative to body weight than fleas. The Frog Hopper can accelerate at 4000 m/s^2 over 2mm as it jumps. Many species resemble leafhoppers, but can be distinguished by the possession of only a few stout spines on the hind tibia, where leafhoppers have a series of small spines. Members of the family Machaerotidae greatly resemble treehoppers, due to a large thoracic spine, but the spine in machaerotids is an enlargement of the scutellum, where treehoppers have the pronotum enlarged. Members of the family Clastopteridae have their wings modified to form false heads at the tail end, an anti-predator adaptation. Many adult Cercopidae can bleed reflexively from their tarsi, and the hemolymph appears to be distasteful; they are often aposematically colored
