This list of mythical creatures that begin with this letter and I am constantly gathering information from each continent, and is continually being updated.
Eleionomae (Greek)
The Eleionomae or Heleionomai (Ancient Greek:, "marsh dwelling" derived from heleios and nomos) were the naiads of marshes and wetlands in ancient Greek mythology. Aside from living in marshy environments, the Eleionomae often misled travelers with their illusions. The illusions constituted images of a traveler's loved ones. These nymphs also lured young, virgin boys and seduced them with their beauty.
Many reports from adventurers mention sighting a colossal tree in the distance that appears to have grown upside down, its roots branching out into the sky while its canopy rests on the swamp floor. Some believe this is the home of the Eleionomae, though any who attempt to approach have found themselves turned around, coming out back where they started.