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The dragonfly is an
insect belonging to the Order Odonata, Suborder Anisoptera and
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 usually found around lakes, ponds, streams,
and wetlands for the reason that their larvae (known as nymphs)
are aquatic. Dragonflies do not bite or sting humans.[1] In fact,
they are valued as a predator that helps control the populations
of insects that do, such as mosquitoes.
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The life cycle
of the dragonfly, from egg to death of adult, is from six months
to as much as six or seven years. Sometimes female dragonflies
lay eggs in the small cleft between mud or moss. Most of their
life time is spent in the larval (nymph) form, beneath the water
surface, using gills to breathe, catching other invertebrates
or even vertebrates such as tadpoles and fish. In the adult (flying)
stage, larger species of dragonfly can live as long as four months.
Dragonflies have very good eyesight due to their unique eye structure.
Dragonflies have about 30,000 facets to their eyes, arranged to
give them nearly a 360° field of vision. Much larger dragonfly
species existed in the distant past than occur on earth today.
The largest, found as a fossil, is an extinct Protodonata from
the Permian period with a wingspan of 70–75 cm (27.5–29.5
in). This compares to 19 cm (7.5 in) for the largest modern species
of odonates, the Hawaiian endemic dragonfly, Anax strenuus, and
the Central American giant damselfly, Megaloprepus coerulatus.
The smallest modern species recorded is the libellulid dragonfly,
Nannophya pygmaea from east Asia with a wing span of only 20 mm,
or about 3/4 of an inch.
Picture Number 1 Is From The U.S. Fish & Wildlife Service
Pictures 2 And 3 And From The N.O.A.A.
Pictures 4 Through 6 Are From The N.R.C.S.
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