Zachariel: A demon bound to appear only once per day, Zachariel belongs to the tenth portion of time when the hours and minutes of the day have been divided into fifteen equal parts. According to the Ars Theurgia, this demon holds the rank of duke, and he has no fewer than two thousand two hundred ministering spirits to attend to his needs. He is ruled by the demon Icosiel, described as a wandering prince of the air.

Source : The Dictionary of Demons written by Michelle Belanger.