Dragonflies are invertebrates, Insecta, Odonata and paraptera. The base of the rear wing is slightly larger than that of the front wing, and the wing veins are also slightly different. At rest, the four wings spread out and lay flat on both sides. The larvae are short and thick, with rectal gills and tailless gills. There are 11 families, including 3 families, including dragonflies, macrodragonflies and dragonflies. Dragonflies and dragonflies are the most common and widely distributed throughout China.

Dragonflies are carnivorous insects. They prey on a variety of agricultural, forestry and animal husbandry pests such as flies, mosquitoes, leaf cicadas, flies, midges and small butterfly moths. Dragonflies are a kind of important natural enemy insects beneficial to mankind. "Dragonfly skimming the water" is the biological feature of dragonfly laying eggs in the water. Its larvae (juveniles) live in water, and the life period varies according to species. Dragonflies generally last for 2 years, and some last for 3 to 5 years. It can be used to monitor environmental pollution and has medicinal, edible and ornamental value.