Like dragonflies everywhere, our desert species start life as a tiny egg, not much larger than the period at the end of this sentence. Most species scatter their eggs freely over a waterway or insert them into vegetation that is floating in or overhanging water. Some eggs hatch within weeks; others over winter before hatching. The larval stage is called a nymph or, more properly, a larva. Dragonfly larvae look like fierce dragons and crawl about underwater hunting for food. A unique feature is their labium, a lower lip that they project to hook prey. While damselfly larvae have feather-like gills at the end of their abdomen, dragonfly larvae do not. All go through about a dozen molts, or instars, before crawling out onto a stem or rock to emerge.
After a period of time, from a month or two to even a few years of growing and molting, the larva crawls out of the water. Its skin then cracks open over the thorax. The adult dragonfly slowly emerges from this old shell; some species even hang down from it limply at first. Then after its legs harden, it pulls itself upright and its body and wings begin to expand and harden. After an hour or more the new adult dragonfly flies off. The empty shell that is left behind is called the exuvia.
Most adult dragonflies live for only several weeks or months; adult damselflies live for an even shorter period. During this time they feed on mosquitoes, gnats and other small insects (at a rate of very many each day); they mature sexually, and then mate.
Male dragonflies defend territories while awaiting the females or actively search for them. When the male finds a female, he grasps the female with the clasp-like holders at the end of his abdomen. Mating occurs in the unique “wheel” position. The females can use ovipositors to insert their eggs into plant stems or just scatter them over the water, sometimes ovipositing while in tandem flight with the male. The larvae that hatch develop without need of parenting
2006-06-07 06:18:23
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answer #1
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answered by cowgirl_nc_21 2
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In the greater Southwest , there are 117 species & different colors. Adults can live from a few weeks to a few months; and eat mosquitoes & gnats . Dragonflies predate dinosaurs . I have a red-orange male flying over my pool , that has become very territorial lately , diving toward me whenever I clean the pool .They are said not to bite humans , but this is a most unusual dragonfly ..
2006-06-06 12:29:45
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answer #2
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answered by missmayzie 7
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"The dragonfly spends most of its life as larvae, spending 1-3 years underwater. Flying adults have a relatively short life span. If lucky, they can survive for six or seven months in warm and dry climates. "
2006-06-06 12:18:00
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answer #3
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answered by kendra 6
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