Quetzalcoatl was a feathered-serpent deity worshiped by the Toltec on Earth.
In 2270, Captain Kirk and the USS Enterprise encountered Kukulkan, an alien being who had visited Earth in the ancient past. Kirk surmised that the legend of Kukulkan was the source of the Toltec worship of Quetzalcoatl. (TAS: "How Sharper Than a Serpent's Tooth")
As of 2373, Jean-Luc Picard had a stone carving depicting Quetzalcoatl in his ready room aboard the USS Enterprise-E. (Star Trek: First Contact)