Dragonfly is a general term for insects of the order Odonata. It is an ancient insect that appeared as early as 0.3 billion years ago in the Carboniferous. The body is slender, with two pairs of transparent wings, wings covered with mesh veins, flying ability is extremely strong. The head has a pair of compound eyes, which are large and prominent, with a wide field of vision, and can keenly capture flying insects. Mainly living near the waters, the larvae live in the water and feed on small organisms in the water. Adulthood in the air to prey on mosquitoes, flies and other small insects, is the famous "air hunter". It flies extremely fast and can make sharp turns and hover. Is an important beneficial insect.

Dragonflies are a class of ancient insects belonging to the order Odonata. They have a slender body with two pairs of transparent and multi-winged wings that flatten out on either side of the body at rest. The head has a pair of compound eyes, which occupy most of the head, making it have excellent visual ability and can keenly capture moving objects. Incomplete metamorphosis insect. The larvae live in water, breathe through the gills, and prey on small aquatic organisms. The adults, on the other hand, fly through the air, feed on other insects and are excellent fliers, able to move, hover and turn quickly in the air. It is widely distributed around the world, especially in tropical and subtropical regions.

Dragonflies are a class of ancient insects belonging to the order Odonata. They have a slender body with two pairs of transparent and multi-winged wings that flatten out on either side of the body at rest. The head has a pair of compound eyes, which occupy most of the head, making it have excellent visual ability and can keenly capture moving objects. Incomplete metamorphosis insect. The larvae live in water, breathe through the gills, and prey on small aquatic organisms. The adults, on the other hand, fly through the air, feed on other insects and are excellent fliers, able to move, hover and turn quickly in the air. It is widely distributed around the world, especially in tropical and subtropical regions.

It is a primitive and diverse group of insects, with approximately 5000 species worldwide. Belonging to semi metamorphosis, it undergoes three stages throughout its life: egg, juvenile, and adult. Wings have unique mechanical structures, making them excellent flyers in nature. They prefer damp environments and usually fly in ponds or riverbanks, where their larvae develop in the water. Playing an important role in ecosystems, larvae can monitor water pollution, while adults prey on agricultural pests such as small moths. Beautiful in appearance, with ornamental value, and some species of larvae and pupae also have edible value. History can be traced back to 320 million years ago, when it was once a 'giant' in the sky.

Planaeschna milnei (scientific name: Planaeschna milnei) is an insect belonging to the family of dragonflies and the genus Planaeschna. Males have a belly length of 56-57 millimeters and hind wings of 45-46 millimeters. Females have a belly length of 53-56 millimeters and hind wings of 47-50 millimeters. Males have a yellow middle lip and black brown side leaves. The base half of the upper lip is yellow green. The base of the front lip is brown, and the base of the back lip is green. The upper forehead is yellow green, with most of the forehead black, forming a shovel shaped black spot with the front edge of the upper forehead. The antennae and back are black. Black chest, black chest and back, with yellow green stripes. Yellow green on the chest side, with black stripes. Black feet with yellow spots on the forefoot. The wings are transparent, and there are wing moles.

The dragonfly is an insect animal of the genus Odonata. Dragonfly has well-developed wings, and the base of hindwing is slightly larger than the base of forewing. At rest, the four wings are spread out and laid flat on both sides. The head is flexible and has short antennae. The compound eye is well-developed, with three monocular eyes and powerful chewing mouthparts. The abdomen is slender, with thin and weak feet and hooked thorns. The larvae are short and thick, with rectal gills and tailless. Dragonfly is a typical incomplete metamorphosis insects, but also the eyes of the most insects. "Compendium of Materia Medica" contains: "Dragonfly, said its tail green also; Wing rainbow, said its shape alone also, or cloud its tail as nails also, or cloud its tail good high and upright. Therefore, it is called, flying, and flying."