سنجاقک

Dragonflies and their more slender relatives, damselflies, are members of the insect order Odonata. This order is among the most ancient of insect groups. Dragonfly ancestors first appeared during the early Carboniferous, about 340 million years ago, with the true Odonata appearing in the Permian, about 275 million years ago. Early dragonflies and their ancestors ranged greatly in size, from the smallest species ever known, with a wingspan of 1.85 cm (0.73 in), to a dragonfly ancestor with a wingspan of about 71 cm (28 in). Today, our largest dragonfly species is about 14 cm (5.5 in) in wingspan.

Adult dragonflies are strong and agile flying predators, spending much of their time in the air catching their winged insect prey. Their immature stages, however, are aquatic and voracious predators of many types of aquatic life from small insects to minnows as large as themselves. The Odonata are unusual among insects in that the male reproductive organs are located near the head-end of the abdomen. This accounts for the common sight in the summer of two dragonflies flying attached over a pond -- the male in the lead, clasping the female with appendages on the tip of its abdomen, and the female bending its abdomen forward to contact the male. With their acrobatic flying and the variety of colors sported by different species, dragonflies and damselflies turn a summer pond into an aerial circus!