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.
Nopal is a common name in Spanish for Opuntia cacti, as well as for its pads.
Echinopsis is a genus of cacti native to South America, sometimes known as hedgehog cactus, sea-urchin cactus or Easter lily cactus. As of October 2023, there are about 20 accepted species, ranging from large and treelike types to small globose cacti. The name derives from echinos hedgehog or sea urchin, and opsis appearance, a reference to these plants' dense coverings of spines.
Opuntia microdasys is a species of flowering plant in the cactus family Cactaceae, native and endemic to central and northern Mexico.
Opuntia ficus-indica, the Indian fig opuntia, fig opuntia, or prickly pear, is a species of cactus that has long been a domesticated crop plant grown in agricultural economies throughout arid and semiarid parts of the world. O. ficus-indica is the most widespread and most commercially important cactus. It is grown primarily as a fruit crop, and also for the vegetable nopales and other uses. Cacti are good crops for dry areas because they efficiently convert water into biomass. O. ficus-indica, as the most widespread of the long-domesticated cactuses, is as economically important as maize and blue agave in Mexico. Opuntia species hybridize easily, but the wild origin of O. ficus-indica is likely to have been in central Mexico, where its closest genetic relatives are found.
Cactoblastis cactorum, the cactus moth, South American cactus moth or nopal moth, is native to Argentina, Paraguay, Uruguay and southern Brazil. It is one of five species in the genus Cactoblastis that inhabit South America, where many parasitoids, predators and pathogens control the expansion of the moths' population. This species has been introduced into many areas outside its natural range, including Australia, the Caribbean, and South Africa. In some locations, it has spread uncontrollably and was consequently classified an invasive species. However, in other places such as Australia, it has gained favor for its role in the biological control of cacti from the genus Opuntia, such as prickly pear.
Opuntioideae is a subfamily of the cactus family, Cactaceae. It contains 15 genera divided into five tribes. The subfamily encompasses roughly 220–250 species, and is geographically distributed throughout the New World from Canada, to Argentina. Members of this subfamily have diverse habits, including small geophytes, hemispherical cushions, shrubs, trees, and columnar cacti consisting of indeterminate branches or determinate terete or spherical segments.
Opuntia engelmannii is a prickly pear common across the south-central and Southwestern United States and northern Mexico. It goes by a variety of common names, including desert prickly pear, discus prickly pear, Engelmann's prickly pear in the US, and nopal, abrojo, joconostle, and vela de coyote in Mexico.
Opuntia stricta is a species of large cactus that is endemic to the subtropical and tropical coastal areas of the Americas, especially around the Caribbean. Common names include erect prickly pear and nopal estricto (Spanish). The first description as Cactus strictus was published in 1803 by Adrian Hardy Haworth. In 1812 he moved the species to the genus Opuntia.
Opuntia leucotricha is a species of cactus with the common names: arborescent pricklypear, Aaron's beard cactus, and semaphore cactus; and duraznillo blanco and nopal blanco.
Opuntia basilaris, the beavertail cactus or beavertail pricklypear, is a cactus species found in the southwest United States. It occurs mostly in the Mojave, Anza-Borrego, and Colorado Deserts, as well as in the Colorado Plateau and northwest Mexico. It is also found throughout the Grand Canyon and Colorado River region as well as into southern Utah and Nevada, and in the western Arizona regions along the Lower Colorado River Valley.
Opuntia humifusa, commonly known as the devil's-tongue, eastern prickly pear or Indian fig, is a cactus of the genus Opuntia present in parts of the eastern United States, Mississippi and northeastern Mexico.
Opuntia fragilis, known by the common names brittle pricklypear and little prickly pear, is a prickly pear cactus native to much of western North America as well as some midwestern states such as Illinois, Iowa, Wisconsin and Michigan. It also occurs in several Canadian provinces. It is known from farther north than any other cactus, occurring at as far as 56°N latitude in British Columbia. There is an isolated and possibly genetically unique population in Eastern Ontario known as the "Kaladar population".
Opuntia, commonly called the prickly pear cactus, is a genus of flowering plants in the cactus family Cactaceae, many known for their flavorful fruit and showy flowers. Prickly pear alone is more commonly used to refer exclusively to the fruit, but may also be used for the plant itself; in addition, other names given to the plant and its specific parts include tuna (fruit), sabra, sabbar, nopal from the Nahuatl word nōpalli, nostle (fruit) from the Nahuatl word nōchtli, and paddle cactus. The genus is named for the Ancient Greek city of Opus, where, according to Theophrastus, an edible plant grew and could be propagated by rooting its leaves. The most common culinary species is the Indian fig opuntia (O. ficus-indica).
Opuntia robusta, the wheel cactus, nopal tapon, or camuesa, is a species of cactus in the family Cactaceae. It is native and endemic to central and northern Mexico to within 100 miles (160 km) of the Arizona and New Mexico borders where it grow from 5,000 to 10,000 feet on rocky slopes, open shrub lands, woodlands and mixed with other cactus and succulents.
Many cacti are known to be psychoactive, containing phenethylamine alkaloids such as mescaline. However, the two main ritualistic (folkloric) genera are Echinopsis, of which the most psychoactive species occur in the San Pedro cactus group, and Lophophora, with peyote being the most psychoactive species. Several other species pertaining to other genera are also psychoactive, though not always used with a ritualistic intent.
Opuntia matudae, or xoconostle, is a cactus native to Mexico. It is sometimes treated as a synonym of Opuntia hyptiacantha. In 2019, a genetic study supported keeping the taxa distinct.
Opuntia cochenillifera is a species of cactus in the subfamily Opuntioideae. It may have been endemic to Mexico, but has been widely introduced. The first description was in 1753 by Carl Linnaeus as Cactus cochenillifer. Philip Miller renamed it as Opuntia cochenillifera in 1768.
Opuntia elata is a species of cactus found in Bolivia, Paraguay, southern Brazil, northern Argentina, and Uruguay.
Opuntia huajuapensis, commonly known as the Huajuapan prickly pear or the Chumbera, is a species of prickly pear cactus in the family Cactaceae. It was described by Helia Bravo Hollis in 1953, and named for the town of Heroica Ciudad Huajuapan de León, Oaxaca, from which the first specimens were described.
