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.
Epiphyllum is a genus of epiphytic plants in the cactus family (Cactaceae), native to Central America and South America. Common names for these species include climbing cacti, orchid cacti and leaf cacti, though the latter also refers to the genus Pereskia.
Disocactus is a genus of epiphytic cacti in the tribe Hylocereeae found in Central America, the Caribbean and northern South America. It should not be confused with Discocactus, which is a different genus.
Pseudorhipsalis is genus of cacti. This genus is often included in Disocactus. It is epiphytic, many branched, and elongated with flattened, serrated cladodes. In its early life, it stands erect, but soon becomes prostrate. It produces numerous flowers.
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 ackermannii commonly called red orchid cactus is an epiphytic cactus from tropical forests in the states of Veracruz and Oaxaca, Mexico. In cultivation, it has been confused with Disocactus × jenkinsonii, a hybrid between D. phyllanthoides and D. speciosus.
Disocactus crenatus, commonly known as the crenate orchid cactus, is a species of cactus cultivated for its large flowers. It is a critical parent plant in creating epiphyllum hybrids commonly cultivated worldwide.
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.
Disocactus phyllanthoides, the nopalxochitl or German empress, is a species of flowering plant in the cactus family Cactaceae. It is commonly grown as an ornamental houseplant. It is one of the three major species involved in creating the widely grown epiphyllum hybrids or "epis". The others are Disocactus speciosus and Disocactus crenatus.
Selenicereus anthonyanus is a cactus species native to southern Mexico. It is grown as an ornamental because of its nocturnal flowers and unusual, leaf-like stems. Common names include fishbone cactus, rickrack cactus, zig-zag cactus and St. Anthony's rickrack, and is sometimes referred to as an orchid cactus.
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.
Disocactus anguliger, commonly known as the fishbone cactus or zig zag cactus, is a cactus species native to Mexico. The species is commonly grown as an ornamental for its fragrant flowers in the fall.
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.
Epiphyllum laui is a cactus species native to Mexico and grown as an ornamental.
Selenicereus megalanthus, synonym Hylocereus megalanthus, is a cactus species in the genus Selenicereus that is native to northern South America, where it is known, along with its fruit, by the name of pitahaya. The species is grown commercially for its yellow fruit, but is also an impressive ornamental climbing vine with perhaps the largest flowers of all cacti.
Aporocactus martianus is a species of cactus found in Oaxaca, Mexico.
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.
Epiphyllum hybrids, epiphyllums, epicacti, or just epis, also known as orchid cacti, which are widely grown for their flowers, are artificial hybrids derived primarily from species of the genus Disocactus. These Disocactus species are not true epiphyllums, but they used to be included in the genus Epiphyllum.
Kimnachia is a monotypic genus of cacti. Its only species is Kimnachia ramulosa, synonym Pseudorhipsalis ramulosa, which is native from southern Mexico to northern South America and also found in Jamaica.
Deamia testudo is a species of flowering plant in the family Cactaceae, native from southern Mexico through Central America to Nicaragua. It was first described in 1838. It is a climber or clamberer, with long stems and large white flowers.
