說明/ 體長6–7 公分，複眼深綠色，合胸黑色，胸前有倒「八」字的黃斑，胸側有4條粗細不一的黃色斜斑。腹部黑色，腹背有黃斑，第8 節下有兩個黑色扇突。翅透明，翅痣黑色。常見於4–11 月，廣泛分布於平地到低海拔的湖泊或池塘等靜水區域。雄蟲常停棲在岸邊突出物上，非常醒目，也會在岸邊來回巡戈，是臺灣少數生活在靜水環境的春蜓之一，雌蟲會點水產卵。本種為食蟲性，會捕食大型獵物，包括其他蜻蜓，本校則可於寧靜湖上游觀察到其蹤跡。（陳家駒攝）
It is about 6-7 cm in length. The compound eyes are dark green. The synthorax is black with an inverted V-shaped yellow stripe. There are tilted yellow stripes of varying widths on the body sides. The abdomen is black with yellow stripes on the back. The 8th segment has two black fan-like expansions. The wings are transparent with black stigmas. It is often seen between April and November and widely distributed across plains and low altitude lakes or ponds and other still waters. The male is often seen staying on protruding objects by the river, or cruising along the shore, belonging to one of the few Gomphidae dragonflies that inhabit still waters in Taiwan. The female dips its abdomen into the water to lay eggs. It is insectivorous and hunts large-sized prey, including other dragonflies. On campus, it can be seen in the upstream area of Tranquility Lake. (Photo courtesy of Chen Jia-ju)