The Oniyanma (Anotogaster sieboldii), also known as the golden-ringed dragonfly, jumbo dragonfly, or Siebold's dragonfly, is the largest species of dragonfly native to Eastern Asia, especially Japan, China, Korean Peninsula. It can grow between 95 and 100 mm in length.

In Japan, dragonflies symbolize approaching autumn and are admired and respected so much that they were symbols of courage, strength, happiness, agility, power, and even victory.

Dragonflies as a Symbol of the Japanese SamuraiThe Japanese Samurai honored the dragonfly in many ways. In the 17th century, high raking Japanese lords used dragonfly shaped helmets so they could be easily identified on the battlefield. The dragonfly image was often emblazoned on the hilts of swords, breastplates and arrow quivers. Because dragonflies were thought to be fearless, swift and courageous, they were believed to bring soldiers strength and protection.

The dragonfly was known as the victory insect because it would quickly advance towards its target and efficiently kill a pest (e.g. mosquitos and horseflies) without hesitation or retreat. In a Japanese legend, an emperor had a horsefly bite him on the arm while out hunting. Before the horsefly could bite him again, a dragonfly swooped down and ate the offending insect. The emperor was so impressed by the dragonfly that he named the region he was in Akitsu-no or Dragonfly Plain.