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.
Euphorbia is a very large and diverse genus of flowering plants, commonly called spurge, in the family Euphorbiaceae. "Euphorbia" is sometimes used in ordinary English to collectively refer to all members of Euphorbiaceae, not just to members of the genus.
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.
Echinocereus is a genus of ribbed, usually small to medium-sized, cylindrical shaped cacti, comprising about 70 species native to the southern United States and Mexico in very sunny, rocky places. Usually the flowers are large and the fruit edible.
Pereskia is a small genus of about four species of cacti that do not look much like other types of cacti, having substantial leaves and non-succulent stems. The genus is named after Nicolas-Claude Fabri de Peiresc, a 16th-century French botanist. The genus was more widely circumscribed until molecular phylogenetic studies showed that it was paraphyletic. The majority of species have since been transferred to Leuenbergeria and Rhodocactus. Although Pereskia does not resemble other cacti in its overall morphology, close examination shows spines developing from areoles, and the distinctive floral cup of the cactus family.
Bergerocactus emoryi is a species of cactus, known commonly as the golden-spined cereus, golden snake cactus, velvet cactus or golden club cactus. It is a relatively small cactus, but it can form dense thickets or colonies, with the dense yellow spines giving off a velvety appearance when backlit by the sun. From April to May, yellow, green-tinged flowers emerge, which transform into reddish, globular fruit. This species is native to the California Floristic Province, and is found in northwestern Baja California and a small part of California, in San Diego County and on the southern Channel Islands. Where the Mediterranean climate of the California Floristic Province collides with the subtropical Sonoran Desert near El Rosario, hybrids with two other species of cacti are found. It is the sole member of the monotypic genus Bergerocactus, named after German botanist Alwin Berger.
Rhipsalis is a genus of epiphytic flowering plants in the cactus family, typically known as mistletoe cacti. They are found in parts of Central America, the Caribbean and northern regions of South America. They also inhabit isolated locations in Africa and Asia, and are the only cactus group naturally occurring in the Old World. This is the largest and most widely distributed genus of epiphytic cacti.
Ariocarpus agavoides is a species of cactus. It is endemic to Mexico. It grows in dry shrubland in rocky calcareous substrates. Some taxonomists place it in a separate genus as Neogomezia agavoides. The locals use the slime from the roots of the plants as glue to repair pottery. The sweet-tasting warts are eaten and often added to salads
In botany, succulent plants, also known as succulents, are plants with parts that are thickened, fleshy, and engorged, usually to retain water in arid climates or soil conditions. The word succulent comes from the Latin word sucus, meaning "juice" or "sap".
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 curvispina 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.
Lithops viridis is a species of plant in the family Aizoaceae.
Pseudolithos is a genus of succulent flowering plants of the family Apocynaceae, indigenous to arid areas of Somalia, Yemen and Oman.
Haworthia parksiana is a species of succulent plant native to the Western Cape of South Africa. Regarded as the smallest and one of the rarest types of Haworthia in the wild, it is thought to be most closely related to Haworthia floribunda. It grows in rosettes up to about 4 centimetres (1.6 in) in diameter, and is often hidden in the ground.
Pseudolithos cubiformis is a species of succulent plant native to Somalia. While its genus name, Pseudolithos, refers to its stone-like appearance, the species is especially named for its squat, leafless, and often cube-shaped growth habit.
Hoya pubicalyx is a species of flowering plant in the genus Hoya native to the Philippines. Sometimes confused for Hoya carnosa, it has succulent, lanceolate foliage and grows in a vining habit epiphytically. Kept as a houseplant in temperate climates, it can be found in variegated forms in nurseries. The Philippine five-centavo coin of the New Generation Currency Series features the flowers of this plant.
Pseudolithos horwoodii is a species of succulent plant in the genus Pseudolithos. Native to arid areas of Somalia, it is a small, leafless plant up to 80 millimetres (3.1 in) tall and 45–60 millimetres (1.8–2.4 in) wide. Its growth habit is squat, unbranched, and blob-like, living up to the name of its genus which means "false stone". Its color is green to grayish brown.
Pseudolithos caput-viperae is a species of succulent plant in the genus Pseudolithos. It is a small, leafless plant up to 15–40 millimetres (0.59–1.57 in) tall and either green or brownish. First discovered and described in the 1970s by botanists John Jacob Lavranos and Renato Bavazzano, it is native to Somalia. The seedlings of the plant are identical to Pseudolithos migiurtinus, but start to branch after a year, making this the only member of Pseudolithos that is not just a single squat stem. Its Latin species name means "snake head".
Crassula tecta is a species of succulent plant in the genus Crassula native to South Africa. Easily confused with Crassula namaquensis, this species has a compact growth habit forming clusters of round, blue-white leaves. Kept in cultivation since the 18th century, Crassula tecta is known for the beautiful patterning on its leaves and white flowers.
Dracaena hallii is a species of succulent plant native to Mozambique, Zimbabwe, and Limpopo Province of South Africa. The species was named for Harry Hall, formerly the curator of succulents at Kirstenbosch National Botanical Garden in Cape Town. Commonly known as the "baseball bat" plant, it has extremely thick foliage with a rounded shape and a central channel.
