The cicadas () are a superfamily, the Cicadoidea, of in the order Hemiptera (true bugs). They are in the suborder Auchenorrhyncha, along with smaller jumping bugs such as and . The superfamily is divided into two families, the Tettigarctidae, with two species in Australia, and the Cicadidae, with more than 3,000 species described from around the world; many species remain undescribed. Nearly all cicada species are with the exception of the few North American periodical cicada species, genus Magicicada, which in a given region emerge en masse every 13 or 17 years.
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 drum-like . 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 crypsis. 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.
One exclusively North American genus, Magicicada (the periodical cicadas), which spend most of their lives as underground nymphs, emerge in predictable intervals of 13 or 17 years, depending on the species and the location. The unusual duration and synchronization 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 that 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 are species that emerge every year. Though these cicadas' life cycles can vary from 1 to 9 or more years as underground nymphs, their emergence above ground as adults is not synchronized, so some members of each species appear every year.
Cicadas have been featured in literature since the time of Homer's Iliad and as motifs in art from the Chinese Shang dynasty. Insect singers orthsoc.org 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), in which it is said to sing when millet first ripens. Cicadas are eaten by humans in various parts of the world, including China, Myanmar, Malaysia, central Africa and parts of Mexico.
At least 3,000 cicada species are distributed worldwide, in essentially any habitat that has deciduous trees, 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 Asia. There are several hundred described species in Australia and New Zealand, around 150 in South Africa, over 170 in America north of Mexico, at least 800 in Latin America, and over 200 in Southeast Asia and the Western Pacific.
About 100 species occur in the Palearctic realm. A few species are found in southern Europe, and a single species was known from England, the New Forest cicada, Cicadetta montana, which also occurs in continental Europe.
Many of the North American species are the annual or jarfly or dog days cicadas, members of the Neotibicen, Megatibicen, or Hadoa genera, so named because they emerge in late July and August. The best-known North American genus, however, may be Magicicada. These periodical cicadas have an extremely long life cycle of 13 or 17 years, with adults suddenly and briefly emerging in large numbers.
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, Psaltoda moerens, greengrocer, yellow Monday, whisky drinker, double drummer, and black prince. The Australian greengrocer, Cyclochila australasiae, is among the loudest insects in the world.
More than 40 species from five genera populate New Zealand, ranging from sea level to mountain tops, and all are endemism to New Zealand and its surrounding islands (Kermadec Islands, Chatham Islands). One species is found on Norfolk Island, which technically is part of Australia. The closest relatives of the NZ cicadas live in New Caledonia and Australia.
The Palaeontinidae or "giant cicadas" (though only distantly related to true cicadas) come from the Jurassic and Lower Cretaceous of Eurasia and South America. The first of these was a fore wing discovered in the Taynton Limestone Formation of Oxfordshire, England; it was initially described as a butterfly in 1873, before being recognised as a cicada-like form and renamed Palaeontina oolitica.
Tettigarctidae and Cicadidae had diverged from each other prior to or during the Jurassic, as evidenced by fossils related to both lineages present by the Middle Jurassic (~165 million years ago). The morphology of well preserved fossils of early relatives of Cicadidae from the mid Cretaceous Burmese amber of Myanmar suggests that unlike many modern cicadids, they were either silent or only made quiet sounds. Most fossil Cicadidae are known from the Cenozoic, and the oldest unambiguously identified modern cicadid is Davispia bearcreekensis (subfamily Tibicininae) from the Paleocene, around 56–59 million years ago.
Cicadas are feeble jumpers, and nymphs lack the ability to jump altogether. Another defining characteristic is the adaptations of the fore limbs of nymphs for underground life. The relict family Tettigarctidae differs from the Cicadidae in having the prothorax extending as far as the scutellum, and by lacking the tympanal apparatus.
The adult insect, known as an imago, is in total length in most species. The largest, the empress cicada ( Megapomponia imperatoria), has a head-body length around , and its wingspan is .
The thorax has three segments and houses the powerful wing muscles. They have two pairs of membranous wings that may be hyaline, cloudy, or pigmented. The wing venation varies between species and may help in identification. The middle thoracic segment has an operculum on the underside, which may extend posteriorly and obscure parts of the abdomen. The abdomen is segmented, with the hindermost segments housing the reproductive organs, and terminates in females with a large, saw-edged ovipositor. In males, the abdomen is largely hollow and used as a resonating chamber.
The surface of the fore wing is superhydrophobic; it is covered with minute, waxy cones, blunt spikes that create a water-repellent film. Rain rolls across the surface, removing dirt in the process. In the absence of rain, dew condenses on the wings. When the droplets coalesce, the cicada leaps several millimetres into the air, which also serves to clean the wings.
The male abdomen in some species is largely hollow, and acts as a sound box. By rapidly vibrating these membranes, a cicada combines the clicks into apparently continuous notes, and enlarged chambers derived from the tracheae serve as resonating chambers with which it amplifies the sound. The cicada also modulates the song by positioning its abdomen toward or away from the substrate (their perch). Partly by the pattern in which it combines the clicks, each species produces its own distinctive mating songs and acoustic signals, ensuring that the song attracts only appropriate mates. The Tettigarctidae have rudimentary tymbals in both sexes and do not produce airborne sounds, rather, both males and females produce vibrations that are transmitted through the tree they perch upon. They are considered as representing the original state from which other cicada communication has evolved.
Average temperature of the natural habitat for the South American species Fidicinini is about . During sound production, the temperature of the tymbal muscles was found to be significantly higher. Many cicadas sing most actively during the hottest hours of a summer day; roughly a Circadian rhythm. Most cicadas are diurnal in their calling and Poikilotherm to warm them up, while a few are capable of raising their temperatures using muscle action and some species are known to call at dusk. Kanakia gigas and Froggattoides typicus are among the few that are known to be truly nocturnal and there may be other nocturnal species living in tropical forests.
Cicadas call from varying heights on trees. Where multiple species occur, the species may use different heights and timing of calling. While the vast majority of cicadas call from above the ground, two Californian species, Okanagana and O. vanduzeei are known to call from hollows made at the base of the tree below the ground level. The adaptive significance is unclear, as the calls are not amplified or modified by the burrow structure, but this may avoid predation.
Although only males produce the cicadas' distinctive sounds, both sexes have membranous structures called tympanal organ (singular – tympanum) by which they detect sounds, the equivalent of having ears. Males disable their own tympana while calling, thereby preventing damage to their hearing; a necessity partly because some cicadas produce sounds up to 120 dB (SPL) which is among the loudest of all insect-produced sounds. The song is loud enough to cause permanent hearing loss in humans should the cicada be at "close range". In contrast, some small species have songs so high in pitch that they are inaudible to humans.
For the human ear, telling precisely where a cicada song originates is often difficult. The pitch is nearly constant, the sound is continuous to the human ear, and cicadas sing in scattered groups. In addition to the mating song, many species have a distinct distress call, usually a broken and erratic sound emitted by the insect when seized or panicked. Some species also have courtship songs, generally quieter, and produced after a female has been drawn to the calling song. Males also produce encounter calls, whether in courtship or to maintain personal space within choruses.
The songs of cicadas are considered by entomologists to be unique to a given species, and a number of resources exist to collect and analyse cicada sounds.
When the eggs hatch, the newly hatched nymphs drop to the ground and burrow. Cicadas live underground as nymphs for most of their lives at depths of about . Nymphs have strong front legs for digging and excavating chambers near to roots, where they feed on xylem sap. In the process, their bodies and interior of the burrow become coated in anal fluids. In wet habitats, larger species construct mud towers above ground to aerate their burrows. In the final nymphal instar, they construct an exit tunnel to the surface and emerge. They then ecdysis (shed their skins) on a nearby plant for the last time, and emerge as adults. The exuviae or abandoned exoskeletons remain, still clinging to the bark of the tree.
Most cicadas go through a life cycle that lasts 2–5 years. Some species have much longer life cycles, such as the North American genus, Magicicada, which has a number of distinct "broods" that go through either a 17-year (Brood XIII), or in some parts of the region, a 13-year (Brood XIX) life cycle The long life cycles may have developed as a response to predation, such as the sphecius and mantis.
Cicadas excrete fluid in streams of droplets due to their high volume consumption of xylem sap. The jets of urine that cicadas produce have a velocity of up to 3 meters per second, making them the fastest among all assessed animals, including mammals like elephants and horses.
Several fungal diseases infect and kill adult cicadas, while other fungi in the genera Ophiocordyceps and Isaria attack nymphs. Massospora cicadina specifically attacks the adults of periodical cicadas, the spores remaining dormant in the soil between outbreaks. This fungus is also capable of dosing cicadas with psilocybin, the psychedelic drug found in magic mushrooms, as well as cathinone, an alkaloid similar to various amphetamines. These chemicals alter the behaviour of the cicadas, driving males to copulate, including attempts with males, and is thought to be beneficial to the fungus, as the fungal spores are dispersed by a larger number of infected carriers.
Plants can also defend themselves against cicadas. Although cicadas can feed on the roots of gymnosperms, it has been found that resinous conifers such as pine do not allow the eggs of Magicicada to hatch, the resin sealing up the egg cavities.
Some cicadas such as Hemisciera maculipennis display bright deimatic flash coloration on their hind wings when threatened; the sudden contrast helps to startle predators, giving the cicadas time to escape. Most cicadas are Diurnality and rely on camouflage when at rest, but some species use aposematism-related Batesian mimicry, wearing the bright colors that warn of toxicity in other animals; the Malaysian Huechys sanguinea has conspicuous red and black warning coloration, is diurnal, and boldly flies about in full view of possible predators.
Predators such as the Sarcophagidae fly Emblemasoma hunt cicadas by sound, being attracted to their songs. Singing males soften their song so that the attention of the listener gets distracted to neighbouring louder singers, or cease singing altogether as a predator approaches. A loud cicada song, especially in chorus, has been asserted to repel predators, but observations of predator responses refute the claim.
In the Japanese novel The Tale of Genji, the title character poetically likens one of his many love interests to a cicada for the way she delicately sheds her robe the way a cicada sheds its shell when molting. Cicada exuviae play a role in the manga Winter Cicada. Cicadas are a frequent subject of haiku, where, depending on type, they can indicate spring, summer, or autumn.. Shaun Tan's illustrated book Cicada tells the story of a hardworking but underappreciated cicada working in an office. Branden Jacobs-Jenkins's play Appropriate takes place on an Arkansas farm in summer, and calls for the sounds of mating cicadas to underscore the entire show.
In North America and Mexico, there is a well-known song, "La Cigarra" ("The Cicada"), written by Raymundo Perez Soto, which is a song in the Mariachi tradition, that romanticises the insect as a creature that sings until it dies.
Brazilian artist Lenine with his track "Malvadeza" from the album Chão, creates a song built upon the sound of the cicada that can be heard along the track.
Cicada sounds heavily feature on the 2021 album Solar Power by New Zealand artist Lorde. She described cicada song as being emblematic of the New Zealand summer.
The cicada has represented since classical antiquity. Jean de La Fontaine began his collection of fables Les fables de La Fontaine with the story "La Cigale et la Fourmi" ("The Cicada and the Ant") based on one of Aesop's fables; in it, the cicada spends the summer singing, while the ant stores away food, and the cicada finds herself without food when the weather turns bitter.
In Chinese tradition, the cicada (蟬, chán) symbolises rebirth and immortality. In the Chinese essay "Thirty-Six Stratagems", the phrase "to shed the golden cicada skin" () is the poetic name for using a decoy (leaving the exuviae) to fool enemies. In the Chinese classic novel Journey to the West (16th century), the protagonist Priest of Tang was named the Golden Cicada.
In Japan, the cicada is associated with the summer season. For many Japanese people, summer hasn't officially begun until the first songs of the cicada are heard. According to Lafcadio Hearn, the song of Meimuna opalifera, called tsuku-tsuku boshi, is said to indicate the end of summer, and it is called so because of its particular call.
In the Homeric Hymns, the goddess Aphrodite retells the legend of how Eos, the goddess of the dawn, requested Zeus to let her lover Tithonus live forever as an Immortality. Zeus granted her request, but because Eos forgot to ask him to also make Tithonus ageless, Tithonus never died, but he did grow old. Eventually, he became so tiny and shriveled that he turned into the first cicada. The Greeks also used a cicada sitting on a harp as an emblem of music.
In Kapampangan mythology in the Philippines, the goddess of dusk, Sisilim, is said to be greeted by the sounds and appearances of cicadas whenever she appears.
Cicadas are not major agricultural pests, but in some outbreak years, trees may be overwhelmed by the sheer numbers of females laying their eggs in the shoots. Small trees may wilt and larger trees may lose small branches. Although in general, the feeding activities of the nymphs do little damage, during the year before an outbreak of periodic cicadas, the large nymphs feed heavily and plant growth may suffer. Some species have turned from wild grasses to sugarcane, which affects the crop adversely, and in a few isolated cases, females have oviposited on such as , grape vines, citrus trees, asparagus, and cotton.
Cicadas sometimes cause damage to ornamental shrubs and trees, mainly in the form of scarring left on tree branches where the females have laid their eggs. Branches of young trees may die as a result..
Biology
Description
Bacteria landing on the wing surface are not repelled; rather, their membranes are torn apart by the nanoscale-sized spikes, making the wing surface the first-known biomaterial that can kill bacteria.
Temperature regulation
Song
Life cycle
Diet
Locomotion
Predators, parasites, and pathogens
Antipredator adaptations
In human culture
In art and literature
In fashion
As food and folk medicine
In music
In mythology and folklore
As pests
See also
Notes
Further reading
External links
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