Huang Long (黄竜 or 黄龙, Yellow Dragon, Japanse:Kōryū or Ōryū, Korean:Hwang-Ryong) is a hornless dragon who once emerged from the River Luo and presented the legendary Emperor Fu Xi with the elements of writing. According to legend, when it appeared before Fu Xi, it filled a hole in the sky made by the monster Kung Kung. Its waking, sleeping and breathing determined day and night, season and weather.
In East Asian culture, there's sometimes a fifth Guardian Beast of the Ssu Ling. This deity is the guardian of the center and it represents the element earth, the Chinese quintessence, as well as the changing of the seasons.
Huang Long doesn't appear in Japanese mythology: the fifth element in the Japanese elemental system is Void. So there cannot be an animal representing it. Because of this, Huang Long is often forgotten. However, some consider the Ouryu (Ōryū, yellow dragon) as the Japanese counterpart of Huang Long since they share some similarities.