Dragonfly, invertebrates, insects, Odonata, Anisoptera insect known. The general body than the Ti big wings, long and narrow, membranous, reticulate vein is very clear. Monocular visual extremely sensitive, 3; 1 pair of antennae, thin and short; chewing mouthparts. Abdominal elongated, flat or cylindrical, distal anal appendages. Foot is thin and weak, a barb, can fly in the sky to catch insects. Naiad nymph, in water using rectal tracheal gills. Generally the more than 11 molt, take 2 years or above 2 years only along the grass to climb out of the water, and then by the last molt eclosion adult. Nymph in water can be predatory larvae or other small animal, sometimes also find similar food. In addition to the large number of prey mosquitoes, flies, butterflies, moths, and some also prey on pest insects such as bees.