Libellulidae

April to October

Korea, Japan, China and Taiwan

The abdomen and hind wings are around 35∼40- and 40∼43-millimeter-long respectively. Males are grayish blue with the back side of the head in dark brown, frontal tubercle in black, and thorax and abdomen covered with white powder in a gray ground. Females are lemon yellow with frontal tubercle in black, and forehead, clypeus, back side of the head, upper labrum, thorax and abdomen in yellow. The abdomen has black stripes on the third to sixth segments, the seventh to ninth ones are black, and the tenth is milk white.

They are mostly observed in June to August, and males win their sphere of power by siting on sand floors, rocks, branches or grass stems. After mating, females alone or protected by male lay their eggs in swamp, reservoir or pond full of water plants by flying over the water just like hitting the surface.