Dragonfly

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Anisoptera redirects here. For the genus of trees see Anisoptera (tree).

Dragonfly
Yellow-winged Darter
Scientific classification
Kingdom: Animalia Phylum: Arthropoda Class: Insecta Order: Odonata Suborder: Epiprocta Infraorder: Anisoptera Selys, 1800
Families
Aeshnidae Austropetaliidae Cordulegastridae Corduliidae Gomphidae Libellulidae Macromiidae Neopetaliidae Petaluridae

A dragonfly is a type of insect belonging to the order Odonata, the suborder Epiprocta or, in the strict sense, the infraorder Anisoptera. It is characterized by large multifaceted eyes, two pairs of strong, transparent wings, and an elongated body.

Dragonflies typically eat mosquitoes, midges, and other small insects like flies, bees, and butterflies. They are therefore valued as predators, since they help control populations of harmful insects. Dragonflies are usually found around lakes, ponds, streams and wetlands because their larvae, known as "nymphs", are aquatic. Dragonflies do not bite or sting humans.

Contents 1 Dragonfly characteristics 2 Life Cycle 3 Classification 3.1 Ancient dragonflies ("Anisozygoptera") 3.2 Dragonflies and damselflies 4 Some common species of the Northern Hemisphere 5 Some common species of the Southern Hemisphere 6 Dragonflies in culture 7 Gallery 8 See also 9 References 10 External links 10.1 Photo Galleries

[edit] Dragonfly characteristics

Male Dragonflies are capable of hovering followed by rapid acceleration. Some nymphs even hunt on land,^[1] an aptitude which could easily have been more common in ancient times when terrestrial predators were clumsier. Giant dragonflies can glide for 20 meters at 10 degrees and a speed of 74 cm per second which is similar to some birds.^[2] They capture their prey by clasping them in legs studded with spikes. Prey cannot escape by diving away because dragonflies always attack from below.

[edit] Life Cycle

Female dragonflies lay eggs in or near water, often on floating or emergent plants. When laying eggs, some species will submerge themselves completely in order to lay their eggs on a good surface. Most of a dragonfly's life is spent in the larvae, (naiad, that is, nymph) form, beneath the water's surface, using internal gills to breathe, and using extendable jaws to catch other invertebrates or even vertebrates such as tadpoles and fish. The larval stage of large dragonflies may last as long as five years. In smaller species, this stage may last between two months and three years. When the larva is ready to metamorphose into an adult, it climbs up a reed or other emergent plant at night. Exposure to air causes the larvae to begin breathing. The skin splits at a weak spot behind the head and the adult dragonfly crawls out of its old larval skin, waits for the sun to rise, pumps up its wings, and flies off to feed on midges and flies. The adult stage of larger species of dragonfly can last as long as four months.

[edit] Classification

[edit] Ancient dragonflies ("Anisozygoptera")

Formerly, the Anisoptera were given suborder rank beside the "ancient dragonflies" (Anisozygoptera) which were believed to contain the two living species of the genus Epiophlebia and numerous fossil ones. More recently it turned out that the "anisozygopterans" form a paraphyletic assemblage of morphologically primitive relatives of the Anisoptera. Thus, the Anisoptera (true dragonflies) are reduced to an infraorder in the new suborder Epiprocta (dragonflies in general). The artificial grouping Anisozygoptera is disbanded, its members being largely recognized as extinct offshoots at various stages of dragonfly evolution. The two living species formerly placed there — the Asian relict dragonflies — form the infraorder Epiophlebioptera alongside the Anisoptera.

[edit] Dragonflies and damselflies

Damselflies (suborder Zygoptera) are often confused with dragonflies, but these are distinct; most damselflies hold their wings at rest together above the body or held slightly open above (such as in the family Lestidae), whereas most dragonflies at rest hold their wings horizontally or occasionally slightly down and forward. Also, the back wing of the dragonfly broadens near the base, caudal to the connecting point at the body, while the back wing of the damselfly is essentially similar to the front wing.The eyes on a damselfly are apart; in most dragonflies the eyes touch. Notable exceptions to this rule are the Petaluridae (Petaltails) and the Gomphidae (Clubtails).

[edit] Some common species of the Northern Hemisphere

Emperor, Anax imperator Keeled Skimmer, Orthetrum coerulescens Black-tailed Skimmer, Orthetrum cancellatum Common Whitetail, Libellula lydia Migrant Hawker, Aeshna mixta Azure Hawker, Aeshna caerulea Southern Hawker, Aeshna cyanea Norfolk Hawker, Aeshna isosceles Common Hawker, Aeshna juncea Red-veined Darter, Sympetrum fonscolombii Common Darter, Sympetrum striolatum Vagrant Darter, Sympetrum vulgatum

Yellow-winged Darter, Sympetrum flaveolum Broad-bodied Chaser, Libellula depressa Four-spotted Chaser, Libellula quadrimaculata Scarce Chaser, Libellula fulva Green Darner, Anax junius Downy Emerald, Cordulia aenea Blue-eyed Darner, Aeshna multicolor Roseate Skimmer, Orthemis ferruginea Widow Skimmer, Libellula luctuosa Great Pondhawk, Erythemis vesiculosa Comet Darner, Anax longipes Banded Pennant, Celithemis fasciata

[edit] Some common species of the Southern Hemisphere

Glistening Demoiselle Phaon iridipennis Dancing Jewel Platycypha caligata Mountain Malachite Chlorolestes fasciatus Common Spreadwing Lestes plagiatus Common Threadtail Elattoneura glauca Goldtail Allocnemis leucosticta Swamp Bluet Africallagma glaucum Pinhey's Whisp Agriocnemis pinheyi Black-tailed Bluet Azuragrion nigridorsum Common Citril Ceriagrion glabrum Yellow-faced Sprite Pseudagrion citricola Gambel's Sprite Pseudagrion gamblesi Hagen's Sprite Pseudagrion hageni

Hamon's Sprite Pseudagrion hamoni Kersten's Sprite Psuedagrion kersteni Masai Sprite Pseudagrion massaicum Salisbury Sprite Pseudagrion salisburyense Natal Sprite Pseudagrion spernatum Orange Emperor Anax speratus Common Thorntail Ceratogomphus pictus Yellowjack Notogomphus praetorius Rock Hooktail Paragomphus cognatus Acisoma Acisoma panorpoides and Acisoma trifidum Banded Groundling Brachythemis leucosticta Broad Scarlet Crocothemis erythraea

Little Scarlet Crocothemis sanguinolenta Black Percher Diplacodes lefebvrii Black-tailed Skimmer Nesciothemis farinosa Two-striped Skimmer Orthetrum caffrum Epaulet Skimmer Orthetrum chrysostigma Julia Skimmer Orthetrum julia St. Lucia Widow Palpopleura portia Nomad Sympetrum fonscolombii Red-veined Dropwing Trithemas arteriosa Navy Dropwing Trithemis furva Kirby's Dropwing Trithemis kirbyi Jaunty Dropwing Trithemis stictica

[edit] Dragonflies in culture

In Europe, dragonflies have often been seen as sinister. Some English vernacular names, such as "devil's darning needle" and "ear cutter", link them with evil or injury.^[3] A Romanian folk tale says that the dragonfly was once a horse possessed by the devil. This is also seen in the Maltese culture as the word for dragonfly which is "Debba ta' l-infern" literally means Hell's mare. Swedish folklore holds that the devil uses dragonflies to weigh people's souls.^[4] Another Swedish legend holds that trolls use the dragonflies as spindles when weaving their clothes (hence the Swedish word for dragonfly trollslända, lit. "troll's spindle") as well as sending them to poke out the eyes of their enemies.^{[citation needed]} The Norwegian name for dragonflies is "Øyenstikker", which literally means Eye Poker. They are often associated with snakes, as in the Welsh name gwas-y-neidr, "adder's servant".^[3] The Southern United States term "snake doctor" refers to a folk belief that dragonflies follow snakes around and stitch them back together if they are injured.^[5] The Lithuanian word "Laumžirgis" is a composite word meaning "the Lauma's horse", while in Dutch, Aeshna mixta is called "Paardenbijter" or "horse biter". In some South American countries, dragonflies are also called matacaballo (horse killer), or caballito del diablo (devil's horse), since they were perceived as harmful, some species being quite large for an insect.

In East Asia and among Native Americans, dragonflies have a far better reputation, one that can also be said to have positively influenced modern day views about dragonflies in most countries.

For some Native American tribes they represent swiftness and activity, and for the Navajo they symbolize pure water. Dragonflies are a common motif in Zuni pottery; stylized as a double-barred cross, they appear in Hopi rock art and on Pueblo necklaces.^[6] It is said in some Native American beliefs that dragonflies are a symbol of renewal after a time of great hardship.

In Japan dragonflies are symbols of courage, strength, and happiness, and they often appear in art and literature, especially haiku. In ancient mythology, Japan was known as Akitsushima, which means "Land of the Dragonflies". The love for dragonflies is reflected by the fact that there are traditional names for almost all of the 200 species of dragonflies found in and around Japan.^[7] Japanese children catch large dragonflies as a game, using a hair with a small pebble tied to each end, which they throw into the air. The dragonfly mistakes the pebbles for prey, gets tangled in the hair, and is dragged to the ground by the weight.^[8]

Also, in Japan, amongst the Three Great Spears of Japan is one which is called the Tonbo-giri, which when translated is called 'The Dragon Fly Cutter'. The spear is an important part of Japans imperial regalia- the spear itself was once wielded by the legendary Samurai, Honda Tadakatsu. It's name is derived from the story that the blade is so sharp, a dragon fly once landed on it and was instantly cut in half.

They also have traditional uses as medicine in Japan and China. In some parts of the world they are a food source, eaten either as adults or larvae; in Indonesia, for example, they are caught on poles made sticky with birdlime, then fried in oil as a delicacy.^[3]

Vietnamese people have a traditional way to forecast rain by seeing dragonflies: "Chuồn chuồn bay thấp thì mưa, bay cao thì nắng, bay vừa thì râm" (Dragonflies fly at low level, it is rainy; dragonflies fly at high level, it is sunny; dragonflies fly at medium level, it is shadowy).

Images of dragonflies were common in Art Nouveau, especially in jewelry designs.^[9] They have also been used as a decorative motif on fabrics and home furnishings.^[10]

[edit] Gallery

Australian blue dragonfly	African dragonfly perched on a leaf	Green Darner Dragonfly feeding on honey bee	Austrogomphus guerini
Ruby Meadowhawk dragonfly, Sympetrum rubicundulum	Dragonfly in midflight over a creek	The compound eyes of a dragonfly	Cherry-faced Meadowhawk, Sympetrum internum
Dragonflies mating	Mating	Mating	Dragonfly depositing eggs
Dragonfly from Lower Silesia (Poland) - bottom	Dragonfly from Lower Silesia - top		California Spreadwing Archilestes californicus
Indian pied paddy skimmer female	Indian pied paddy skimmer male	in Brazos Bend State Park, Texas, USA	Blue Dragonfly in a temple in Kamakura, Japan
Sardinian Dragonfly	Female Red-veined darter. Lisboa, Portugal

[edit] See also

• Elliot Pinhey
• Obelisk posture
• List of British dragonflies

[edit] References

[edit] External links

• Tree of Life Odonata
• Dragonfly at the Open Directory Project
• Dragonflies of North America - diagnostic photos and information
• Identification key to dragonflies found in Ireland
• British Dragonfly Society
• List of Anisoptera of the World
• Photos of most British species
• Dragonflies and Damselflies (Odonata) of the United States
• Photogallery by Dan Bárta et al. + some texts in Czech
• DragonflyIndia Group
• PHAON (Pinhey's Heritage African Odonata Network)
• Odonatologica
• Photos of South African species
• Maps, photographs and additional information pertaining to the Odonata of North America
• Short film, Emergence of a Dragonfly
• Asian Dragonfly
• Dragonflies in folklore and art

[edit] Photo Galleries

• Dragonlfies and Damselflies