THE OPHIES PTERETOI were a breed of feathery-winged Serpents which guarded the frankincense groves of Arabia. They were sometimes called Ophies Amphipterotoi, or "Serpents with Two-Pairs of Wings."
Herodotus, Histories 2. 75. 1-4 (trans. Godley) (Greek historian C5th B.C.) :
"There is a place in Arabia not far from the town of Bouto (Buto) where I went to learn about the Winged Serpents (ophies pteretoi). When I arrived there, I saw innumerable bones and backbones of serpents: many heaps of backbones, great and small and even smaller. This place, where the backbones lay scattered, is where a narrow mountain pass opens into a great plain, which adjoins the plain of Aigyptos (Egypt).
Winged serpents (ophies pteretoi) are said to fly from Arabia at the beginning of spring, making for Egypt; but the ibis birds encounter the invaders in this pass and kill them. The Arabians say that the ibis is greatly honored by the Aigyptoi (Egyptians) for this service, and the Aigyptoi give the same reason for honoring these birds."
Herodotus, Histories 3. 107. 1 - 110.1 :
"Again, Arabia is the most distant to the south of all inhabited countries: and this is the only country which produces frankincense and myrrh and casia and cinnamon and gum-mastich. All these except myrrh are difficult for the Arabians to get. They gather frankincense by burning that storax which Phoinikes (Phoenicians) carry to Hellas; they burn this and so get the frankincense; for the spice-bearing trees are guarded by small Winged Snakes (ophies hypopteroi) of varied color, many around each tree; these are the snakes that attack Aigyptos (Egypt). Nothing except the smoke of storax will drive them away from the trees . . .
So too if the vipers and the Winged Serpents (ophies hypopteroi) of Arabia were born in the natural manner of serpents life would be impossible for men; but as it is, when they copulate, while the male is in the act of procreation and as soon as he has ejaculated his seed, the female seizes him by the neck, and does not let go until she has bitten through. The male dies in the way described, but the female suffers in return for the male the following punishment: avenging their father, the young while they are still within the womb gnaw at their mother and eating through her bowels thus make their way out. Other snakes, that do no harm to men, lay eggs and hatch out a vast number of young. The Arabian Winged Serpents do indeed seem to be numerous; but that is because (although there are vipers in every land) these are all in Arabia and are found nowhere else.
The Arabians get frankincense in the foregoing way."
Aelian, On Animals 2. 38 (trans. Scholfield) (Greek natural history C2nd A.D.) :
"The Black Ibis does not permit the Winged Serpents (Ophies Pterotoi) from Arabia to cross into Aigyptos (Egypt), but fights to protect the land it loves."
Aelian, On Animals 16. 41 :
"Megasthenes states that in India there are . . . snakes (ophies) with wings, and that their visitations occur not during the daytime but by night, and that they emit urine which at once produces a festering wound on any body on which it may happen to drop."
- Herodotus, Histories - Greek History C5th B.C.
- Aelian, On Animals - Greek Natural History C2nd - C3rd A.D.