Chalkydri

In the apocryphal Second Book of Enoch (likely the 7th century AD), there is a creature called the "Chalkydri," or the "Kalkydra," which translates to English as either "Brazen Hydras," or "Copper Serpents." these serpentine creatures are considered to be a type of archangel.

Description
The excerpts below are from the Second Book of Enoch:
 * "And I looked and saw other flying elements of the sun, whose names Phoenixes and Chalkydri, marvelous and wonderful, with feet and tails in the form of a lion, and a crocodile’s head, their appearance  empurpled, like the rainbow; their size nine hundred measures, their wings those of angels, each twelve, and they attend and accompany the sun, bearing heat and dew, as it is ordered them from God. "


 * "Then the elements of the sun, called Phoenixes and Chalkydri break into song, therefore every bird flutters with its wings, rejoicing at the giver of light, and they broke into song at the command of the Lord. "

An excerpt from "A Dictionary of Angels, Including the Fallen Ones," by Gustav Davidson (1967) sates about the Chalkydri:
 * "(They are) archangels of the flying elements of the sun. Mentioned in Enoch II, where they are linked with the Phoenixes and placed amidst Cherubim and Seraphim. The Chalkydri are 12-winged. At the rising of the sun they burst into song. Their habitat is the 4th Heaven. In Gnostic lore, they are demonic. In Charles' Introduction to Enoch II, the Chalkydri are described as "monstrous serpents with the heads of crocodiles" and as "natural products of the Egyptian imagination. ""