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Cactaceae
A cactus (, or less commonly, 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 word (''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. Although some species live in quite humid environments, 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. 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 spine ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pereskioideae
A cactus (, or less commonly, 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 word (''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. Although some species live in quite humid environments, 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. 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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Classification Of The Cactaceae
In 1984, the International Organization for Succulent Plant Study set up a working party, now called the International Cactaceae Systematics Group, to produce a consensus classification of the cactus family, down to the level of genus. Their classification has been used as the basis for systems published since the mid-1990s. Treatments in the 21st century have generally divided the family into around 125–130 genera and 1,400–1,500 species, which are then arranged in a number of tribes and subfamilies. However, subsequent molecular phylogenetic studies have shown that a very high proportion of the higher taxa (genera, tribes and subfamilies) are not monophyletic, i.e. they do not contain all of the descendants of a common ancestor. , the internal classification of the family Cactaceae remained uncertain and subject to change. A classification incorporating many of the insights from the molecular studies was produced by Nyffeler and Eggli in 2010. Overview The classificatio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Opuntioideae
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. Description Synapomorphies of Opuntioideae include small deciduous, barbed spines called glochids born on areoles and a bony aril surrounding a campylotropous ovule (inverted and curved, such that the micropyle almost meets the funiculus). Other prominent morphological characters for this subfamily are presence of cylindrical, caducous leaves that tend to be shed by maturity and the sectioning of the stem into joints or pads known as cladodes. Opuntioideae are unique among cacti for lacking in the stem a thick cortex, an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Caryophyllales
Caryophyllales ( ) is a diverse and heterogeneous order of flowering plants that includes the cacti, carnations, amaranths, ice plants, beets, and many carnivorous plants. Many members are succulent, having fleshy stems or leaves. The betalain pigments are unique in plants of this order and occur in all its families with the exception of Caryophyllaceae and Molluginaceae. Description The members of Caryophyllales include about 6% of eudicot species. This order is part of the core eudicots. Currently, the Caryophyllales contains 37 families, 749 genera, and 11,620 species The monophyly of the Caryophyllales has been supported by DNA sequences, cytochrome c sequence data and heritable characters such as anther wall development and vessel-elements with simple perforations. Circumscription As with all taxa, the circumscription of Caryophyllales has changed within various classification systems. All systems recognize a core of families with centrospermous ovules and seeds. Mor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cactoideae
The Cactoideae are the largest subfamily of the cactus family, Cactaceae. Around 80% of cactus species belong to this subfamily. , the internal classification of the family Cactaceae remained uncertain and subject to change. A classification incorporating many of the insights from the molecular studies was produced by Nyffeler and Eggli in 2010. Various revisions have been published since, e.g. to the tribe Hylocereeae and the tribe Echinocereeae. Classifications remained uncertain . Tribes and genera , the National Center for Biotechnology Information used the division of the subfamily into tribes shown below. Some revisions to the circumscriptions of the tribes are also shown. * Blossfeldieae **''Blossfeldia'' *Browningieae **''Armatocereus'' – ''Browningia'' – ''Neoraimondia'' – '' Stetsonia'' *Cacteae **''Acharagma'' – ''Ariocarpus'' – ''Astrophytum'' – ''Aztekium'' – ''Coryphantha'' – '' Cumarinia'' – ''Echin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Opuntia
''Opuntia'', commonly called prickly pear or pear cactus, is a genus of flowering plants in the cactus family Cactaceae. Prickly pears are also known as ''tuna'' (fruit), ''sabra'', '' nopal'' (paddle, plural ''nopales'') from the Nahuatl word for the pads, or nostle, from the Nahuatl word for the fruit; or 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''). Description ''O. ficus-indica'' is a large, trunk-forming, segmented cactus that may grow to with a crown of over in diameter and a trunk diameter of . Cladodes (large pads) are green to blue-green, bearing few spines up to or may be spineless. Prickly pears typically grow with flat, rounded cladodes (also called platyclades) containing large, smooth, fixed spines and small, hairlike prickles called glochids th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Succulent
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". Succulent plants may store water in various structures, such as leaves and stems. The water content of some succulent organs can get up to 90–95%, such as ''Glottiphyllum semicyllindricum'' and ''Mesembryanthemum barkleyii''. Some definitions also include roots, thus geophytes that survive unfavorable periods by dying back to underground storage organs may be regarded as succulents. The habitats of these water-preserving plants are often in areas with high temperatures and low rainfall, such as deserts, but succulents may be found even in alpine ecosystems growing in rocky soil. Succulents are characterized by their ability to thrive on limited water sources, such as mist and dew, which makes them equipped to su ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crassulacean Acid Metabolism
Crassulacean acid metabolism, also known as CAM photosynthesis, is a carbon fixation pathway that evolved in some plants as an adaptation to arid conditions that allows a plant to photosynthesize during the day, but only exchange gases at night. In a plant using full CAM, the stomata in the leaves remain shut during the day to reduce evapotranspiration, but they open at night to collect carbon dioxide () and allow it to diffuse into the mesophyll cells. The is stored as four-carbon malic acid in vacuoles at night, and then in the daytime, the malate is transported to chloroplasts where it is converted back to , which is then used during photosynthesis. The pre-collected is concentrated around the enzyme RuBisCO, increasing photosynthetic efficiency. This mechanism of acid metabolism was first discovered in plants of the family Crassulaceae. Historical background Observations relating to CAM were first made by de Saussure in 1804 in his ''Recherches Chimiques sur la Végétatio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Areole
In botany, areoles are small light- to dark-colored bumps on cacti out of which grow clusters of spines. Areoles are important diagnostic features of cacti, and identify them as a family distinct from other succulent plants. Gordon Rowley - What is an Areole The spines are not easily detachable, but on certain cacti, members of the subfamily Opuntioideae, smaller, detachable bristles, glochids, also grow out of the areoles and afford additional protection. Areoles represent highly specialized branches on cacti. Apparently, they evolved as abortive branch buds while their spines evolved as vestigial leaves. In branched cacti, such as Opuntioidiae and the saguaro, new branches grow from areoles, because that is where the buds are. The development of the areole seems to have been an important element in the adaptation of cacti to niches in desert ecology. Some of the Opuntioideae have spines, as well as glochids, on their areoles; some have only glochids. Structurally, the gloc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Maihuenioideae
''Maihuenia'' is a genus of cactus (family Cactaceae) and the sole genus of the subfamily Maihuenioideae, which is the smallest subfamily of the Cactaceae. The genus comprises two cushion-forming, mucilaginous species. They are found at high elevation habitats of Andean Argentina and Chile Chile, officially the Republic of Chile, is a country in the western part of South America. It is the southernmost country in the world, and the closest to Antarctica, occupying a long and narrow strip of land between the Andes to the eas .... Its name is the Latinized version of ''maihuén'', a local Chilean name for these cacti. Species References Cactaceae genera Cacti of South America Flora of the Andes Flora of Argentina Flora of Chile Maihuenioideae {{Cactus-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rhipsalis Baccifera
''Rhipsalis baccifera'', commonly known as the mistletoe cactus, is an epiphytic cactus which originates from Central and South America, the Caribbean, and Florida. It is also found throughout the tropics of Africa and into Sri Lanka where it is known in Sinhala as (). This is the only cactus species naturally occurring outside the Americas. One hypothesis is that it was introduced to the Old World by migratory birds, long enough ago for the Old World populations to be regarded as distinct subspecies. An alternative hypothesis holds that the species initially crossed the Atlantic Ocean on European ships trading between South America and Africa, after which birds may have spread it more widely., pp. 117–118 Taxonomy The species shows considerable polymorphism and can be divided into numerous subspecies. Mesoamerican specimens are usually tetraploid and South American specimens are diploid. The genera currently assigned to the tribe Rhipsalideae (which include ''Hatiora'', ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thorns, Spines, And Prickles
In plant morphology, thorns, spines, and prickles, and in general spinose structures (sometimes called ''spinose teeth'' or ''spinose apical processes''), are hard, rigid extensions or modifications of leaves, roots, stems or buds with sharp, stiff ends, and generally serve the same function: physically deterring animals from eating the plant material. Description In common language the terms are used more or less interchangeably, but in botanical terms, thorns are derived shoots (so that they may or may not be branched, they may or may not have leaves, and they may or may not arise from a bud),Simpson, M. G. 2010. "Plant Morphology". In: ''Plant Systematics, 2nd. edition''. Elsevier Academic Press. Chapter 9.Judd, Campbell, Kellogg, Stevens, Donoghue. 2007. "Structural and Biochemical Characters". In: ''Plant Systematics, a phylogenetic approach, third edition''. Chapter 4. spines are derived from leaves A leaf ( : leaves) is any of the principal appendages of a v ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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