Quail. . . I'm sure that's not a mythical creature you were expecting. . . .But Quail are known well just as much as a mythical creature as it is a real one. Many cultures recognize Quail as an important mythical creature and all for different reasons.
In China, Quail is associated with the Phoenix because of its bird form, power and beauty. In Taoist belief, the Quail is the Yang out of a yin yang. (I don't know what its Yin would be). In Japan they believe that the quail is the only bird created on earth, all other birds having descended from heaven. Quails are believed to give people certain 'lucks' such as good living, and nourishment.
The different cultures named above are very few in comparison to all the many who believe Quail to be a powerful mythical creature.