A cactus is a member of the plant family Cactaceae, a family comprising about 127 genera with some 1750 known species of the order Caryophyllales. The word "cactus" derives, through Latin, from the Ancient Greek κάκτος, kaktos, 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. Most cacti live in habitats subject to at least some drought. Many live in extremely dry environments, even being found in the Atacama Desert, one of the driest places on earth. Cacti show many adaptations to conserve water. 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 leaves, enlarged stems carry out photosynthesis. Cacti are native to the Americas, ranging from Patagonia in the south to parts of western Canada in the north—except for Rhipsalis baccifera, which also grows in Africa and Sri Lanka.
Mammillaria is one of the largest genera in the cactus family (Cactaceae), with currently 200 known species and varieties recognized. Most of the mammillarias are native to Mexico, but some come from the southwest United States, the Caribbean, Colombia, Venezuela, Guatemala and Honduras. The common name "pincushion cactus" refers to this and the closely related genus Escobaria.
Mammilloydia is a genus of cactus containing the sole species Mammilloydia candida, the snowball cactus.
Fishhook cactus is a common name for any hook-spined species of the genera Mammillaria, Echinomastus or Sclerocactus. They are small cacti, usually growing up to 6-7 inches (20 cm) high, and are shaped similar to a barrel cactus. They are not to be confused with the fishhook barrel cactus of the Sonoran and Chihuahuan Deserts. The Fishhook cactus is a large category of around 150 species.
The strawberry hedgehog cactus or Engelmann's hedgehog cactus is commonly found in desert areas of the southwestern United States and the adjacent areas of Mexico, including the states of California, Nevada, Utah, Arizona, Baja California and Sonora.
Echinocereus reichenbachii is a perennial plant and shrub in the cactus family. The species is native to the Chihuahuan Desert and parts of northern Mexico and the southern United States, where they grow at elevations up to 1,500 meters (4,900 ft). This cactus earned the Royal Horticultural Society's Award of Garden Merit.
Opuntia stricta is a large sized species of cactus that is endemic to the subtropical and tropical coastal areas of the Americas and 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 introduced the species in the genus Opuntia.
Mammillaria painteri is a species of plant in the family Cactaceae. It is endemic to Mexico. It is usually found near, but not limited to, San Juan del Rio, Guanajuato. It is commonly referred to as the biznaguita in Spanish. It is also known by many to be synonymous with Mammillaria crinita subspecies crinita. It was evaluated and added to the IUCN Redlist in 2002 as data deficient. The causes of this species' endangerment or threats to its well-being are not clear.
Mammillaria elongata, the gold lace cactus or ladyfinger cactus, is a species of flowering plant in the family Cactaceae, native to central Mexico. Growing to 15 cm (6 in) tall by 30 cm (12 in) wide, it consists of densely packed clusters of elongated oval stems, covered in harmless yellow or brown spines, and in spring producing white or yellow flowers. It is among the commonest and most variable of its genus in nature, and is a popular subject for cultivation. It has gained the Royal Horticultural Society's Award of Garden Merit.
Mammillaria spinosissima, also known as the spiny pincushion cactus, is a species of flowering plant in the cactus family Cactaceae, endemic to the central Mexican states of Guerrero and Morelos, where they grow at elevations of approximately 1,600 to 1,900 metres. The species was described in 1838 by James Forbes, gardener of the Duke of Bedford. Botanist David Hunt collected a specimen in 1971, when he located one near Sierra de Tepoztlan, Mexico.
Parodia tenuicylindrica is a species of cactus from the genus Parodia. The small green cacti have yellow and red-brown spines, white wool and yellow flowers. They produce yellow-green fruit, and black seeds. P. tenuicylindrica can be found growing individually in Rio Grande do Sul, Brazil.
Parodia arnostiana is a species of cactus in the genus Parodia. The small, squat green plants produce yellow flowers, green fruit and black seeds. The species is found growing in Rio Grande do Sul, Brazil.
Opuntia macrocentra, the long-spined purplish prickly pear or purple pricklypear, is a cactus found in the lower Southwestern United States and Northwestern Mexico. A member of the prickly pear genus, this species of Opuntia is most notable as one of a few cacti that produce a purple pigmentation in the stem. Other common names for this plant include black-spined pricklypear, long-spine prickly pear, purple pricklypear, and redeye prickly pear.
Mammillaria morganiana, common name owl's eyes or owl-eye pincushion, is a cactus in the genus Mammillaria of the family Cactaceae. The epithet morganiana honors the U.S. optometrists Meredith WalterMorgan (1887-1957) of Richmond.
Mammillaria grusonii is a cactus in the genus Mammillaria of the family Cactaceae. The epithet grusonii honors the inventor, scientist, industrialist and cacti collector Hermann Gruson of Magdeburg.
Mammillaria mammilllaris, common name woolly nipple cactus, is a species of plant in the family Cactaceae. It is the type species of the genus Mammillaria. It has been described by Carolus Linnaeus as Cactus mammillaris in 1753. The specific epithet mammillaris comes from the Latin mammilla, meaning nipple, with reference to the characteristic tubercles.
Mammillaria magnimamma, common name Mexican pincushion, is a species of flowering plant in the cactus family Cactaceae.
Mammillaria carmenae, the Isla Carmen pincushion cactus, is a species of flowering plant in the family Cactaceae.
Crassula ovata, commonly known as jade plant, lucky plant, money plant or money tree, is a succulent plant with small pink or white flowers that is native to the KwaZulu-Natal and Eastern Cape provinces of South Africa, and Mozambique; it is common as a houseplant worldwide. Much of its popularity stems from the low levels of care needed; the jade plant requires little water and can survive in most indoor conditions. It is sometimes referred to as the money tree; however, Pachira aquatica also has this nickname.
Mammillaria sphaerica, the longmamma nipple cactus or pale mammillaria is a species of flowering plant in the cactus family Cactaceae, native to south eastern Texas in the USA and north eastern Mexico, where it occurs in scattered patches at altitudes up to 1,000 m (3,300 ft). It forms clumps of small pale green spheres to 5 cm (2.0 in) in diameter, with short hairs and pale yellow flowers up to 3 cm (1.2 in) wide in summer.
