What is "itzamna"

In Yucatec Maya mythology, Itzamna was the name of an upper god and creator deity thought to be residing in the sky. Little is known about him, but scattered references are present in early-colonial Spanish reports (relaciones) and dictionaries. Twentieth-century Lacandon lore includes tales about a creator god ( Nohochakyum or Hachakyum) who may be a late successor to Itzamna. In the pre-Spanish period, Itzamna, represented by the aged god D, was frequently depicted in books and in ceramic scenes derived from such books.