Nymphaea caerulea, known primarily as blue lotus (or blue Egyptian lotus), but also blue water lily (or blue Egyptian water lily), and sacred blue lily (or sacred narcotic lily of the nile), is a water-lily in the genus Nymphaea. Like other species in the genus, the plant contains the psychoactive alkaloid apomorphine. It was known to the Mayan and Ancient Egyptian civilisations. Its original habitat may have been along the Nile and other parts of East Africa. It spread more widely in ancient times, including to the Indian Subcontinent and Thailand.