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Saturday, 6 August 2011

Dragonflies




The egg stage - a male and a female will mate - while they are flying & the female will lay her eggs, usually on a plant in the water. Once the dragonfly eggs hatch, the life cycle of a dragonfly larva begins as a nymph. A nymph, (or, in the case of dragonflies & damselflies more correctly termed naiad), looks like a little alien creature. It hasn’t grown its wings yet and has what looks like a crusty hump hanging onto its back. Nymphs live in the water while they grow and develop into dragonflies. This part of the life cycle can take up to four years to complete, and if the nymph cycle is completed in the beginning of the wintertime, it will remain in the water until spring, when it is warm enough to come out. Nymphs live in ponds or marshy areas where things are calmer than say in a faster running stream or river - though sometimes they can be found in calmer backwaters. Nymphs may eat smaller nymphs as they develop but usually feed gnats, mosquitoes, and other small insects like flies, bees, ants, and - very rarely - butterflies. .

Once the nymph is fully grown, and, if the weather is dry & sunny, it will


metamorphosise into a dragonfly the imago stage ... by crawling out of the water up the stem of a plant or stone. The nymph will shed its skin dry out, becoming an adult. (more strictly it undergoes Hemimetabolism or hemimetaboly, which is also termed incomplete metamorphosis). The exoskeleton/skin left behind is called the exuvia and can often found some time after the dragonfly has left it.



The adult dragonfly will hunt for food and begin to look for a mate and the cycle start all over ...

Adult dragonflies only live about two months.

1 comment:

  1. This one came out of our bottom pond - having escaped been eaten by the fish! It metamorphosised on July 14th ... a kind of 'Independence Day' 10 days late!

    I was pleased that I could film its transistion, and its first flight, using my new Flip HD camera but for some reason I can't upload the movie.

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