Etymology - Named after the Greek moon goddess Selene as the flowers open at night.
The various species that make up the genus Selenicereus are similar in that they are vine-like, climbing plants. Primarily epiphytes, some also grow on rocks. The stems may be mostly round in cross-section, to sharply angled, to flat-jagged, almost fern-like. Some species are spineless, while other have tiny hairlike spines, and still others with more formidable protection. Ariel roots are common along the stem which aid in climbing.
The flowers are night-blooming and rather spectacular and typically fragrant. Some exceed 12 inches in diameter and most have long, slender floral tubes that have scales, hairs, bristles or spines. Fruits are fleshy with persistent spines. Most flowers are all white, some are white in part with red or yellowish outer perianth parts.
In the wild, the species range from Mexico down through Central America, the Caribbean, and into South America. They are mostly rain-forest plants and need a higher amount of moisture to grow than do the desert-dwelling cacti. A number of species are grown quite commonly in cultivation among cactus enthusiasts. They can be found in more specialty nurseries, but are often traded among collectors as they are easily propagated by cuttings.