Cactus

Cactus is the name given to any member of the flowering plant Flowering plant

The flowering plants are a major group of land plant [i]s. ... 

 family Cactaceae. The cacti have adapted to extreme arid environment Environment

An environment is a complex of surrounding circumstances, conditions, or influences in which a thing is ... 

s and show a wide range of anatomical Anatomy

Anatomy , is the branch of biology [i] that deals with the structure and organization of living things [i] ... 

 and physiological features which conserve water. Cacti are often used as ornamental plants, but some are also crop plants.

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Encyclopedia

This article is about the plant family. For the genus Cactus, see Mammillaria Mammillaria

The genus [i] Mammillaria is one of the largest in the cactus family Cactaceae [i], with curr ... 

, Melocactus Melocactus

Melocactus is genus [i] of cactus [i] with about 40 species [i].

... 

 and Opuntia Opuntia

Opuntia is a genus [i] in the cactus family Cactaceae [i]. ... 

.

For other meanings, see Cactus Cactus

Cactus is the name given to any member of the flowering plant [i] family Cactaceae. ... 

.

Cactus is the name given to any member of the flowering plant Flowering plant

The flowering plants are a major group of land plant [i]s.... 

 family Cactaceae. The cacti have adapted to extreme arid environment Environment

An environment is a complex of surrounding circumstances, conditions, or influences in which a thing is ... 

s and show a wide range of anatomical Anatomy

Anatomy , is the branch of biology [i] that deals with the structure and organization of living things [i] ... 

 and physiological features which conserve water. Cacti are often used as ornamental plants, but some are also crop plants.

Distribution and evolution

Cacti are almost exclusively New World New World

The New World is one of the names used for the Americas [i].... 

 plants. This means that they are native only in North America North America

North America is a continent [i] in the Earth [i]'s northern hemisphere [i] and almost fully in the western hemisphere [i]... 

, South America South America

South America is a continent [i] situated in the western hemisphere [i] and, mostly, ... 

, and the West Indies Caribbean

The Caribbean is a region [i] of the Americas [i] consisting of the Caribbean Sea [i], its island [i]s... 

. There is however one exception, Rhipsalis baccifera; this species has a pantropical distribution, occurring in the Old World in tropical Africa Africa

Africa is one of the greatest sized continents of the Earth.... 

, Madagascar Madagascar

Madagascar, , is an island nation [i] in the Indian Ocean [i], off the eastern coast of Africa [i], clos ... 

 and Sri Lanka Sri Lanka

Sri Lanka, officially the Democratic Socialist Republic of Sri Lanka , is a tropical [i] island nation [i] ... 

 as well as in tropical America. This plant is thought to be a relatively recent colonist in the Old World , probably carried as seed Seed

A seed is the ripened ovule [i] of gymnosperm [i] or angiosperm [i] plant [i]s. ... 

s in the digestive tract Gastrointestinal tract

The gastrointestinal tract or digestive tract, also referred to as the GI tract or the al... 

s of migratory Bird migration

Long-distance land bird migration
... 

 bird Bird

Birds are biped [i]al, warm-blooded [i], oviparous [i] vertebrate [i] animals characterized [i] ... 

s. Many other cacti have become naturalized to similar environments in other parts of the world after being introduced by people.

Cacti are believed to have evolved Evolution

In biology [i], evolution is the change in the heritable [i] traits [i] of a population [i] ... 

 in the last 30 to 40 million years. Long ago, the Americas were joined to the other continents, but separated due to continental drift. Unique species in the New World must have developed after the continents had moved apart. Significant distance between the continents was only achieved around in the last 50 million years. This may explain why cacti are so rare in Africa; the continents had already separated when cacti evolved. Many succulent plant Succulent plant

Succulent plants, or succulents, are plant [i]s that store water [i] in enlarged fleshy leave [i] ... 

s in both the Old and New World bear a striking resemblance to cacti, and are often called "cactus" in common usage. This is, however, due to parallel evolution Parallel evolution

Parallel evolution is the independent evolution of similar traits, starting from a similar ancestral con... 

; none of these are closely related to the Cactaceae.

Prickly pear Opuntia

Opuntia is a genus [i] in the cactus family Cactaceae [i]. ... 

s were imported into Australia Australia

Australia, officially the Commonwealth of Australia, is a country in the Southern Hemisphere [i] c ... 

 in the 19th century 19th century

The 19th century lasted from 1801 [i] through 1900 [i] in the Gregorian calendar [i].
... 

 for use as a natural agricultural fence and to establish a cochineal dye Cochineal

Cochineal is the name of both an expensive crimson [i] or carmine [i] dye [i] and the cochineal insec ... 

 industry, but quickly became a widespread weed. This invasive species Invasive species

The term invasive species refers to a subset of those species defined as introduced species [i] or non-indigenous species [i] ... 

 is inedible for local herbivore Herbivore

Herbivore is often defined as any organism [i] that eats only plants. ... 

s and has rendered 40,000 kmē of farming land unproductive.

Adaptations to dry environment

Like other succulents, cacti are well-adapted to life with little precipitation. The leaves Leaf

In botany [i], a leaf is an above-ground plant [i] organ [i] specialized for photosynthesis [i]. ... 

 have evolved into spines, which in addition to allowing less water to evaporate through transpiration than regular leaves, defend the cactus against water-seeking animals. The spines grow from specialised structures called areole. Photosynthesis Photosynthesis

Photosynthesis , generally, is the synthesis of sugar from light [i], carbon dioxide [i] and water, with ... 

 is carried out by enlarged stems, which also store water. Unlike many other succulents, the stem is the only part of a true cactus where this takes place. Very few members of the family have leaves, and when present these are usually rudimentary and soon fall off; they are typically awl-shaped and only 1-3 mm long. Two genera, Pereskia Pereskia

The genus [i] Pereskia comprises 25 tropical [i] species [i] and varieties [i] of leafy cacti [i] ... 

and Pereskiopsis, do however retain large, non-succulent leaves 5-25 cm long, and also non-succulent stems. Pereskia has now been determined to be the ancestral genus from which all other cacti evolved . The roots are often extensive and close to the surface of the ground, an adaptation to infrequent rains. Cacti use the Crassulacean acid metabolism process.


Cacti come in a wide range of shapes and sizes. Some grow to great size. Some cacti produce beautiful flower Flower

A flower,rflorem<flos), also known as a bloom or blossom, is the reprod ... 

s, which like spines and branches arise from areoles. Many cactus species are night-blooming, as they are pollinated Pollination

Pollination is an important step in the reproduction [i] of seed plant [i]s: the transfer of pollen grains [i] ... 

 by nocturnal Nocturnal animal

A nocturnal animal is one that sleeps during the day [i] and is active at night [i] - the opposite of th ... 

 insect Insect

Insects are invertebrate [i]s that are taxonomically [i] referred to as the class Inse ... 

s or small animals, principally moth Moth

A moth is an insect [i] closely related to the butterfly [i]. ... 

s and bat Bat

Bats are mammal [i]s in the order [i] Chiroptera. ... 

s. Cacti range from small and round to pole-like and tall, such as the Saguaro Saguaro

The Saguaro is a large, tree-sized cactus [i] species [i] in the monotypic [i] genus Carnegiea... 

.

Uses

A number of cactus species are cultivated for use as houseplants, as well as for ornamental gardens. They often form part of xerophilic gardens Xeriscaping

Xeriscaping refers to landscaping [i] in ways that do not require supplemental irrigation [i] ... 

 in arid regions. Some cacti bear edible fruit Fruit

The term fruit has different meanings depending on context.... 

.

Etymology

The word cactus is ultimately derived from Greek ?a?t?? kaktos, used in classical Greek for a species of spiny thistle Thistle

Thistle is the common name of a polyphyletic [i] group of flowering plant [i]s characterised b... 

, possibly the cardoon Cardoon

The cardoon, also called the artichoke thistle, is a member of the thistle [i] family related to the Globe artichoke [i] ... 

, and used as a generic name, Cactus, by Linnaeus Carolus Linnaeus

Carolus Linnaeus, also known after his ennoblement [i] as Carl von Linn, , was a ... 

 in 1753 . There is some dispute as to the proper plural form of the word; as a Greek loan into English, the correct plural in English would be "cactuses". However, as a word in Botanical Latin , "cactus" would follow standard Latin rules for pluralization and become "cacti", which has become the prevalent usage in English.

Selected important genera

For a full list see Taxonomy of the Cactaceae Taxonomy of the Cactaceae

Here is the full taxonomy [i] of the family [i] Cactaceae [i]. ... 

Acanthocalycium Acanthocereus Acanthocereus Acanthocereus is a genus [i] of cacti [i]. ...  Acharagma Ariocarpus Ariocarpus Ariocarpus is a genus [i] of cacti [i]....  Armatocereus Armatocereus Armatocereus is a genus [i] of mostly tree-like cacti [i] from South America [i]. ...  Arrojadoa Arthrocereus Astrophytum Astrophytum Astrophytum is a genus [i] of four species of cacti [i]. ...  Austrocactus Austrocylindropuntia Aztekium Aztekium The genus [i] Aztekium contains only two species [i] of small globulary cactus [i]. ...  Bergerocactus Blossfeldia Brachycereus Brasilicereus Brasiliopuntia Cuija The cuija is a species [i] of cactus [i] and the only species in the genus [i] Brasiliopuntia. ...  Browningia Calymmanthium Carnegia Saguaro The Saguaro is a large, tree-sized cactus [i] species [i] in the monotypic [i] genus Carnegiea...  Cephalocereus Cephalocereus Cephalocereus is a small genus [i] of slow-growing, columnar-shaped, blue-green cacti [i]. ...  Cephalocleistocactus Cleistocactus Cleistocactus is a genus [i] of columnar cacti [i] from Peru [i], Uruguay [i], Bolivia [i] and Argentina [i] ...  Cereus Cereus Cereus is a genus [i] of cacti [i]. ...  Cintia Cipocereus Cleistocactus Cleistocactus Cleistocactus is a genus [i] of columnar cacti [i] from Peru [i], Uruguay [i], Bolivia [i] and Argentina [i] ...  Cochemiea Mammillaria The genus [i] Mammillaria is one of the largest in the cactus family Cactaceae [i], with curr ...  Coleocephalocereus Consolea Copiapoa Copiapoa Copiapoa is a genus [i] of cacti [i] from the dry coastal desert [i]s of northern Chile [i]. ...  Corryocactus Coryphantha Coryphantha Coryphantha is a genus [i] of small to middle-sized, globous to short-columnar cacti [i]. ...

Cumulopuntia Cylindropuntia Cylindropuntia Cylindropuntia is a genus [i] of cacti [i]. The genus is also treated as a subgenus [i] of...  Dendrocereus Acanthocereus Acanthocereus is a genus [i] of cacti [i]. ...  Denmoza Denmoza Denmoza is a genus [i] of cactus [i] found in Argentina [i], comprised of only 2 species [i]. ...  Discocactus Disocactus Disocactus Disocactus is genus [i] of epiphytic [i] cacti [i] from Mexico [i] to South America [i] ...  Echinocactus Echinocactus Echinocactus is a genus of large and beautiful barrel-shaped [i] cacti [i], usu ...  Echinocereus Echinocereus [i] [[cactus|cacti]...  Echinomastus Echinomastus Echinomastus is a genus of cacti [i]....  Echinopsis Echinopsis Echinopsis is a large genus [i] of cacti [i] native to South America [i], sometimes referred ...  Epiphyllum Epiphyllum Epiphyllum is a genus [i] of 19 species [i] of epiphytic [i] plant [i]s in the cactus [i] f ...  Epithelantha Button cactus Button cacti or pingpong ball cacti are a genus of cacti [i]. ...  Eriosyce Escobaria Escobaria Escobaria is a genus [i] of low-growing cacti [i] that range from the southernmost parts of c ...  Escontria Espostoa Espostoopsis Eulychnia Facheiroa Ferocactus Frailea Frailea Frailea is a genus [i] of globular to short cylindrical cacti [i] native to Brazil [i]. ...  Geohintonia Grusonia Gymnocalycium Gymnocalycium Gymnocalycium, commonly called chin catcus, is a genus of about 70 South America [i]n species [i] ...  Haageocereus Harrisia Hatiora Hatiora Hatiora is a genus [i] of epiphytic [i] cacti [i] from Brazil [i]. ...  Hylocereus Hylocereus Hylocereus is a genus [i] of cacti [i], often referred to as nightblooming cactus [i]....  Isolatocereus Stenocereus Stenocereus is a genus [i] of columnar or tree-like cacti [i] from the Baja California Peninsula [i] ...  Jasminocereus Jasminocereus Jasminocereus is a genus [i] of cacti [i]. ...  Lasiocereus

Leocereus Leocereus bahiensis Leocereus bahiensis is a species [i] of cactus [i] and the only species of the genus [i] Leocer...  Lepismium Leptocereus Leuchtenbergia Leuchtenbergia Leuchtenbergia principis, the sole species of the genus [i] Leuchtenbergia, is a species [i] ...  Lophophora Lophophora Lophophora is a genus [i] of spineless, button-like cacti [i] native to the southwestern United States [i] ...  Maihuenia Maihueniopsis Maihueniopsis Maihueniopsis is a genus [i] of the cactus family, containing less than 20 species [i]. ...  Mammillaria Mammillaria The genus [i] Mammillaria is one of the largest in the cactus family Cactaceae [i], with curr ...  Mammilloydia Matucana Matucana Matucana is a genus [i] of cacti [i], containing approximately 20 species [i] of mostly globu ...  Melocactus Melocactus Melocactus is genus [i] of cactus [i] with about 40 species [i]. ...  Micranthocereus Mila Miqueliopuntia Myrtillocactus Myrtillocactus Myrtillocactus is a genus [i] of cacti [i]. ...  Neobuxbaumia Neolloydia Neoraimondia Neowerdermannia Obregonia Opuntia Opuntia Opuntia is a genus [i] in the cactus family Cactaceae [i]. ...  Oreocereus Oreocereus Oreocereus is a genus [i] of cacti [i], known only from high altitudes of the Andes [i]. ...  Oroya Ortegocactus Pachycereus Pachycereus Pachycereus is a genus [i] of 9-12 species of large cacti [i], native to Mexico [i] and just ...  Parodia Parodia Parodia is a genus [i] of cacti [i]. ...  Pediocactus Pediocactus Pediocactus is a genus [i] of cacti [i]. ...  Pelecyphora Peniocereus Pereskia Pereskia The genus [i] Pereskia comprises 25 tropical [i] species [i] and varieties [i] of leafy cacti [i] ...

Pereskiopsis Pilosocereus Pilosocereus Pilosocereus is genus [i] of cactus [i]. ...  Polaskia Praecereus Pseudoacanthocereus Pseudorhipsalis Pterocactus Pygmaeocereus Quiabentia Rauhocereus Rebutia Rebutia Rebutia is a genus [i] in the family Cactaceae [i], containing 41 species [i]. ...  Rhipsalis Rhipsalis Rhipsalis is a genus [i] of epiphytic [i], mostly spineless cacti [i]. ...  Samaipaticereus Schlumbergera Schlumbergera Schlumbergera is a genus [i] of 6 known tree [i]-dwelling cacti [i] from Brazil [i]. ...  Sclerocactus Selenicereus Stenocactus Stenocactus Stenocactus is a genus [i] of cacti [i]. ...  Stenocereus Stenocereus Stenocereus is a genus [i] of columnar or tree-like cacti [i] from the Baja California Peninsula [i] ...  Stephanocereus Stetsonia Strombocactus Strombocactus disciformis Strombocactus disciformis is a rare species [i] of cacti [i] and the only species of the genus [i] ...  Tacinga Tephrocactus Tephrocactus Tephrocactus is a genus [i] of the cactus family. ...  Thelocactus Thelocactus Thelocactus is a succulent [i] member of the cactus [i] family. ...  Tunilla Tunilla Tunilla is a South America [i]n genus [i] of the cactus family. ...  Turbinicarpus Turbinicarpus Turbinicarpus is a genus [i] of small to medium-sized cacti [i], originating from the arid l ...  Uebelmannia Weberbauerocereus Weberocereus Yungasocereus

References and external links

• Anderson, Edward F. The Cactus Family ISBN 0-88192-498-9 - Comprehensive and lavishly illustrated
• Benson, Lyman The Cacti of Arizona ISBN 0-8165-0509-8 - Thorough treatment of the Arizona, U.S.A., species
•