The dragon louse is a precious aquatic insect, also known as the water turtle, for the dragon louse family of the size of the genus collectively, belongs to the insect order Coleoptera Carnivora suborder dragon louse family. Lives in fields, ditches, streams and other water bodies, in the water can swim, out of the water can fly, and has a strong tendency to light. Mainly carnivorous, but also plant-eating, especially good at catching small fish and shrimp in the water and aquatic insects. Long lice, commonly known as water turtle, alias Zelao, black shell bug, water turtle, water turtle bug, shooting turtle, small turtle, and so on. Insects, Coleoptera, Carnivora, Long lice family of aquatic insects, there are more than 4,000 kinds of global, a very diverse diet. Dragon lice can swim and fly, living in ponds and swamps with lots of water plants.

The dragon louse is heterozygous, to sexual maturity and development, the male dragon will chase the female dragon louse, with the base of the tarsal joint of its forefoot expanding round sucker (hold foot) attached to the female dragon louse smooth sheath wings on both sides of the front, and climbed to the back of the body of the female dragon louse mating (female dragon louse forefoot without sucker). The female louse lays fertilized eggs in the stalk tissue of the watercress.