Cicada
The cicadas (/sɪˈkɑːdə/ or /sɪˈkeɪdə/) are a superfamily, the Cicadoidea, of insects in the order Hemiptera (true bugs). They are in the suborder Auchenorrhyncha,[a] along with smaller jumping bugs such as leafhoppers and froghoppers. The superfamily is divided into two families, Tettigarctidae, with two species in Australia, and Cicadidae, with more than 3,000 species described from around the world; many species remain undescribed.
Cicadas have prominent eyes set wide apart, short antennae, and membranous front wings. They have an exceptionally loud song, produced in most species by the rapid buckling and unbuckling of drumlike tymbals. The earliest known fossil Cicadomorpha appeared in the Upper Permian period; extant species occur all around the world in temperate to tropical climates. They typically live in trees, feeding on watery sap from xylem tissue and laying their eggs in a slit in the bark. Most cicadas are cryptic. The vast majority of species are active during the day as adults, with some calling at dawn or dusk. Only a rare few species are known to be nocturnal.
The periodic cicadas spend most of their lives as underground nymphs, emerging only after 13 or 17 years. The unusual duration and timing of their emergence may reduce the number of cicadas lost to predation, both by making them a less reliably available prey (so that any predator who evolved to depend on cicadas for sustenance might starve waiting for their emergence), and by emerging in such huge numbers that they will satiate any remaining predators before losing enough of their number to threaten their survival as a species.
The annual cicadas are species that emerge every year. Though these cicadas have lifecycles that can vary from one to nine or more years as underground larvae, their emergence above ground as adults is not synchronized, so some members of each species appear every year.[1]
Cicadas have been featured in literature since the time of Homer's Iliad, and as motifs in art from the Chinese Shang dynasty. They have also been used in myth and folklore as symbols of carefree living and immortality. The cicada is also mentioned in Hesiod's Shield (ll.393-394), its voice sings when millet first ripens. Cicadas are eaten by human beings in various countries, including China, where the nymphs are served deep-fried in Shandong cuisine.
The superfamily Cicadoidea is a sister of the Cercopoidea (the froghoppers). Cicadas are arranged into two families: the Tettigarctidae and Cicadidae. The two extant species of the Tettigarctidae include one in southern Australia and the other in Tasmania. The family Cicadidae is subdivided into the subfamilies Cicadinae, Tibicininae (or Tettigadinae), Tettigomyiinae, and Cicadettinae;[4][5] they are found on all continents except Antarctica. Some previous works also included a family-level taxon called the Tibiceninae. The largest species is the Malaysian emperor cicada Megapomponia imperatoria; its wingspan is up to about 20 cm (8 in).[6] Cicadas are also notable for the great length of time some species take to mature.[7]
At least 3000 cicada species are distributed worldwide with the majority being in the tropics. Most genera are restricted to a single biogeographical region and many species have a very limited range. This high degree of endemism has been used to study the biogeography of complex island groups such as in Indonesia and the Orient.[9] There are several hundred described species in Australia and New Zealand,[c] around 150 in South Africa, over 170 in America north of Mexico,[10] at least 800 in Latin America,[11] and over 200 in Southeast Asia and the Western Pacific.[12] About 100 species occur in the Palaearctic. A few species are found in southern Europe,[7] and a single species was known from England, the New Forest cicada, Cicadetta montana, which also occurs in continental Europe.[13] Many species await formal description and many well-known species are yet to be studied carefully using modern acoustic analysis tools that allow their songs to be characterized.
Many of the North American species are the annual or jarfly or dog-day cicadas, members of the Neotibicen, Megatibicen, or Hadoa genera, so named because they emerge in late July and August.[14] The best-known North American genus, however, may be Magicicada. These periodical cicadas have an extremely long lifecycle of 13 or 17 years, with adults suddenly and briefly emerging in large numbers.[14][15]
Australian cicadas are found on tropical islands and cold coastal beaches around Tasmania, in tropical wetlands, high and low deserts, alpine areas of New South Wales and Victoria, large cities including Sydney, Melbourne, and Brisbane, and Tasmanian highlands and snowfields. Many of them have common names such as cherry nose, brown baker, red eye, greengrocer, yellow Monday, whisky drinker, double drummer, and black prince. The Australian greengrocer, Cyclochila australasiae, is among the loudest insects in the world.[16]
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