Eous
One of the four horses of the sun in classical Greek mythology. According to the poet Ovid, the four horses that drew the chariot of the sun were Eous, Acthon, Phlegon and Pyrios. Like Pegasus they were winged and extremely swift.
John and Caitlin Matthews, The Element Encyclopaedia of Magical Creatures, 2013, Eous, p 167
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