A cactus is a member of the plant family Cactaceae, a family comprising about 127 genera with some 1,750 known species of the order Caryophyllales. The word cactus derives, through Latin, from the Ancient Greek word κάκτος (káktos), a name originally used by Theophrastus for a spiny plant whose identity is now not certain. Cacti occur in a wide range of shapes and sizes. They are native to the Americas, ranging from Patagonia in the south to parts of western Canada in the north, with the exception of Rhipsalis baccifera, which is also found in Africa and Sri Lanka. Cacti are adapted to live in very dry environments, including the Atacama Desert, one of the driest places on Earth. Because of this, cacti show many adaptations to conserve water. For example, almost all cacti are succulents, meaning they have thickened, fleshy parts adapted to store water. Unlike many other succulents, the stem is the only part of most cacti where this vital process takes place. Most species of cacti have lost true leaves, retaining only spines, which are highly modified leaves. As well as defending against herbivores, spines help prevent water loss by reducing air flow close to the cactus and providing some shade. In the absence of true leaves, cacti's enlarged stems carry out photosynthesis.
Night-blooming cereus is the common name referring to a large number of flowering ceroid cacti that bloom at night. The flowers are short lived, and some of these species, such as Selenicereus grandiflorus, bloom only once a year, for a single night, though most put out multiple flowers over a period of several weeks, each of which opens for only a single night. Other names for one or more cacti with this habit are princess of the night, Honolulu queen, Christ in the manger, dama de noche, and queen of the night.
Stenocereus eruca, commonly known as the creeping devil, is a member of the family Cactaceae. It is one of the most distinctive cacti, a member of the relatively small genus Stenocereus. It is endemic to the central Pacific coast of Baja California Sur, and is found only on sandy soils, where it forms massive colonies.
The term ceroid cactus is used to describe any of the species of cacti with very elongated bodies, including columnar growth cacti and epiphytic cacti. The name is from the Latin cēreus, meaning "wax taper ", referring to the stiff, upright form of the columnar species. Some species of ceroid cacti were known as torch cactus or torch-thistle, supposedly due to their use as torches by Native Americans in the past.
Hylocereus is a former genus of epiphytic cacti, often referred to as night-blooming cactus. Several species previously placed in the genus have large edible fruits, which are known as pitayas, pitahayas or dragonfruits. In 2017, a molecular phylogenetic study confirmed an earlier finding that the genus Hylocereus was nested within Selenicereus, so all the species of Hylocereus were transferred to Selenicereus.
Selenicereus, sometimes known as moonlight cactus, is a genus of epiphytic, lithophytic, and terrestrial cacti, found in Mexico, Central America, the Caribbean and northern South America. The term night-blooming cereus is also sometimes used, but this is also used for many night-blooming cacti, including Epiphyllum and Peniocereus. In 2017, the genus Hylocereus was brought into synonymy with Selenicereus. A number of species of Selenicereus produce fruit that is eaten. The fruit, known as pitaya or pitahaya in Spanish or as dragon fruit, may be collected from the wild or the plants may be cultivated.
Selenicereus undatus, the white-fleshed pitahaya, is a species of the genus Selenicereus in the family Cactaceae and is the most cultivated species in the genus. It is used both as an ornamental vine and as a fruit crop - the pitahaya or dragon fruit.
Disocactus crenatus, the crenate orchid cactus, is a species of cactus and a critical parent plant in creating the epiphyllum hybrids commonly cultivated worldwide. It is cultivated for its large flowers.
Selenicereus hamatus is a species of Cactaceae and produces one of the largest flowers in the family. It is a cultivated ornamental vine. The species is native to Mexico.
Selenicereus spinulosus is a cactus species native to eastern Mexico and, possibly, the lower Rio Grande Valley of Texas in the United States. Common names include vine-like moonlight cactus and spiny moon cereus. Its specific name, spinulosus, means "with small spines" in Latin.
Selenicereus costaricensis, synonym Hylocereus costaricensis, known as the Costa Rican pitahaya or Costa Rica nightblooming cactus, is a cactus species native to Central America and north-eastern South America. The species is grown commercially for its fruit, called pitaya or pitahaya, but is also an impressive ornamental vine with huge flowers. The species may not be distinct from Selenicereus monacanthus.
Bipolaris cactivora is a plant pathogen causing cactus stem rot and pitaya fruit rot.
Cereus repandus, the Peruvian apple cactus, is a large, erect, spiny columnar cactus found in South America. It is also known as giant club cactus, hedge cactus, cadushi, and kayush.
Selenicereus grandiflorus is a cactus species originating from the Antilles, Mexico and Central America. The species is commonly referred to as queen of the night, night-blooming cereus, large-flowered cactus, sweet-scented cactus or vanilla cactus. The true species is extremely rare in cultivation. Most of the plants under this name belong to other species or hybrids. It is often confused with the genus Epiphyllum.
A pitaya or pitahaya is the fruit of several different cactus species indigenous to the region of southern Mexico and along the Pacific coasts of Guatemala, Costa Rica, and El Salvador. Pitaya is cultivated in East Asia, South Asia, Southeast Asia, the United States, the Caribbean, Australia, Brazil, and throughout tropical and subtropical regions of the world.
Schlumbergera orssichiana is a species of plant in the family Cactaceae. It is endemic to a small area of the coastal mountains of south-eastern Brazil where its natural habitat is moist forest. It grows on trees as an epiphyte. It is in the same genus as the popular houseplant known as Christmas cactus or Thanksgiving cactus.
The Hylocereeae are a tribe of cacti. Most are found in the tropical forests of Central and northern South America, and are climbers or epiphytes, unlike most cacti. The tribe includes between six and eight genera in different circumscriptions. The plants known as "epiphyllum hybrids" or "epiphyllums", widely grown for their flowers, are hybrids of species within this tribe, particularly Disocactus, Pseudorhipsalis and Selenicereus, less often Epiphyllum, in spite of the common name.
Echinocereus dasyacanthus is a member of the cactus family, Cactaceae. It is one of about 2000 total species belonging to this family. The cactus is commonly known as Texas rainbow cactus because of the subtle rings or bands of contrasting colors along the stem of the plant. Not all Texas rainbow cacti have the "rainbow" coloration on their stems. Another common name is spiny hedgehog cactus.
Strophocactus wittii, synonym Selenicereus wittii, known as the Amazon moonflower, is a species of plant in the genus Strophocactus in the cactus family (Cactaceae), and is one of several species commonly called "moonflowers". It was first described in 1900 and is one of three species of cactus found in the central Amazon basin.
