Epiphyllum oxypetalum

Epiphyllum oxypetalum (Dutchman's pipe or queen of the night) is a species of cactus and one of the most cultivated species in the genus. Though it is sometimes referred to as a nightblooming cereus, it is not closely related to any of the species in the tribe Cereeae, such as Selenicereus, that are more commonly known as nightblooming cereus. All Cereus bloom at night and are terrestrial plants; all Epiphyllum are epiphytic.