Flower of Selenicereus anthonyanus. Photo courtesy of Paul Kaluschke.A native of Chiapas, Mexico, Selenicereus anthonyanus is one of a fairly small group of epiphytic cacti. The strange habit of S. anthonyanus suggests that throughout many thousands of years the climate of the area in which it resided changed from an arid environment to a more tropical environment and S. anthonyanus had to adapt in order to survive. Since rainfall and moisture in this new climate was no longer the most difficult resource to acquire, and sunlight had become scarcer due to the new climate that allowed taller and faster growing plants to shade out low-growing plants, S. anthonyanus developed a broad, slim stem that did not store water as well but was much better at gathering sunlight. In fact, many scientists believe that this thinning and partitioning of sections of the stem is an attempt for these members of the cactus family (Cactaceae) to redevelop the leaves that they lost long ago. In addition to a slimmer leaf-like appearance, the stem produces small adventitious roots along its surface that allow it to grip on to trees and climb as high as possible to obtain maximum light.
Although most people have never seen one in person, the flower of S. anthonyanus is one of its greatest features. It is very difficult to get to bloom, but if one is lucky the results are spectacular. The flower can be as much as a foot across and full of golden stamens. Selenicereus anthonyanus blooms only once a year, however, and only for one night. Pollination in this species is not completely understood, but it is believed that bats are responsible for pollination, which is supported by the nocturnal blooming habit of S. anthonyanus.
