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Phyllachne
''Phyllachne'' is a genus of four cushion plant species in the family Stylidiaceae. Of the four species, two are endemic to New Zealand, while '' P. colensoi'' is also native to Tasmania and '' P. uliginosa'' is entirely endemic to southern South America and is the only species in the Stylidiaceae native to the Americas. The movement of ''P. colensoi'' to colonize Tasmania is a relatively recent move. Molecular studies group ''P. colensoi'', '' P. clavigera'', and '' P. rubra'' together in one clade with ''P. uliginosa'' in the sister clade. Based on molecular clock The molecular clock is a figurative term for a technique that uses the mutation rate of biomolecules to deduce the time in prehistory when two or more life forms diverged. The biomolecular data used for such calculations are usually nucleot ... data of the ''rbcL'' gene, it is estimated that ''P. uliginosa'' last shared a common ancestor with the New Zealand clade about 6 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phyllachne Colensoi
''Phyllachne colensoi'', the yellow cushionplant, is a species of cushion plant in the Stylidiaceae family. It is native to both New Zealand and Tasmania, with colonisation of the latter being a somewhat recent dispersal. ''Phyllachne colensoi'' is frequently the dominant vegetation in upland bog habitats and is found throughout high mountain areas in New Zealand, but is only recorded from 12 sites in Tasmania in the west and south-west of the island.Wagstaff, S.J. and Wege, J. (2002)Patterns of diversification in New Zealand Stylidiaceae ''American Journal of Botany'', 89(5): 865–874.Good, R. (1925). On the geographical distribution of the Stylidiaceae. ''New Phytologist'', 24(4): 225–240.Gray, A. M. (2009) version 2009:2. In M. F. Duretto (Ed.) Flora of Tasmania Online. 9 pp. (Tasmanian Herbarium, Tasmanian Museum & Art Gallery: Hobart). ''Phyllachne colensoi'' is a perennial cushion mound-forming plant with short erect stems that are densely packed. Leaves are sessile ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stylidiaceae
The family Stylidiaceae is a taxon of dicotyledonous flowering plants. It consists of five genera with over 240 species, most of which are endemic to Australia and New Zealand. Members of Stylidiaceae are typically grass-like herbs or small shrubs and can be perennials or annuals. Most species are free standing or self-supporting, though a few can be climbing or scrambling (''Stylidium scandens'' uses leaf tips recurved into hooks to climb). The pollination mechanisms of ''Stylidium'' and '' Levenhookia'' are as follows: In ''Stylidium'' the floral column, which consists of the fused stamen and style, springs violently from one side (usually under the flower) when triggered. This deposits the pollen on a visiting insect. In ''Levenhookia'', however, the column is immobile, but the hooded labellum is triggered and sheds pollen. In 1981, only about 155 species were known in the family. The current number of species by genus (reported in 2002) is as follows: ''Forstera'' - 5, ''L ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
New Zealand
New Zealand () is an island country in the southwestern Pacific Ocean. It consists of two main landmasses—the North Island () and the South Island ()—and List of islands of New Zealand, over 600 smaller islands. It is the List of island countries, sixth-largest island country by area and lies east of Australia across the Tasman Sea and south of the islands of New Caledonia, Fiji, and Tonga. The Geography of New Zealand, country's varied topography and sharp mountain peaks, including the Southern Alps (), owe much to tectonic uplift and volcanic eruptions. Capital of New Zealand, New Zealand's capital city is Wellington, and its most populous city is Auckland. The islands of New Zealand were the last large habitable land to be settled by humans. Between about 1280 and 1350, Polynesians began to settle in the islands and subsequently developed a distinctive Māori culture. In 1642, the Dutch explorer Abel Tasman became the first European to sight and record New Zealand. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Clade
In biology, a clade (), also known as a Monophyly, monophyletic group or natural group, is a group of organisms that is composed of a common ancestor and all of its descendants. Clades are the fundamental unit of cladistics, a modern approach to taxonomy adopted by most biological fields. The common ancestor may be an individual, a population, or a species (extinct or Extant taxon, extant). Clades are nested, one in another, as each branch in turn splits into smaller branches. These splits reflect evolutionary history as populations diverged and evolved independently. Clades are termed ''monophyletic'' (Greek: "one clan") groups. Over the last few decades, the cladistic approach has revolutionized biological classification and revealed surprising evolutionary relationships among organisms. Increasingly, taxonomists try to avoid naming Taxon, taxa that are not clades; that is, taxa that are not Monophyly, monophyletic. Some of the relationships between organisms that the molecul ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Americas
The Americas, sometimes collectively called America, are a landmass comprising the totality of North America and South America.''Webster's New World College Dictionary'', 2010 by Wiley Publishing, Inc., Cleveland, Ohio. When viewed as a single continent, the Americas or America is the 2nd largest continent by area after Asia, and is the 3rd largest continent by population. The Americas make up most of the land in Earth's Western Hemisphere and comprise the New World. Along with their Lists of islands of the Americas, associated islands, the Americas cover 8% of Earth's total surface area and 28.4% of its land area. The topography is dominated by the American Cordillera, a long chain of mountains that runs the length of the west coast. The flatter eastern side of the Americas is dominated by large river basins, such as the Amazon basin, Amazon, St. Lawrence River–Great Lakes, Mississippi River System, Mississippi, and Río de la Plata Basin, La Plata basins. Since the Americ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
South America
South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a considerably smaller portion in the Northern Hemisphere. It can also be described as the southern Subregion#Americas, subregion of the Americas. South America is bordered on the west by the Pacific Ocean, on the north and east by the Atlantic Ocean, and to the south by the Drake Passage; North America and the Caribbean Sea lie to the northwest. The continent includes twelve sovereign states: Argentina, Bolivia, Brazil, Chile, Colombia, Ecuador, Guyana, Paraguay, Peru, Suriname, Uruguay, and Venezuela; two dependent territory, dependent territories: the Falkland Islands and South Georgia and the South Sandwich Islands; and one administrative division, internal territory: French Guiana. The Dutch Caribbean ABC islands (Leeward Antilles), ABC islands (Aruba, Bonaire, and Curaçao) and Trinidad and Tobago are geologically located on the South-American continental shel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tasmania
Tasmania (; palawa kani: ''Lutruwita'') is an island States and territories of Australia, state of Australia. It is located to the south of the Mainland Australia, Australian mainland, and is separated from it by the Bass Strait. The state encompasses the main island of Tasmania, the List of islands by area#Islands, 26th-largest island in the world, and the List of islands of Tasmania, surrounding 1000 islands. It is Australia's smallest and least populous state, with 573,479 residents . The List of Australian capital cities, state capital and largest city is Hobart, with around 40% of the population living in the Greater Hobart area. Estimated resident population, 30 June 2017. Tasmania is the most decentralised state in Australia, with the lowest proportion of its residents living within its capital city. Tasmania's main island was first inhabited by Aboriginal Australians, Aboriginal peoples, who today generally identify as Palawa or Pakana. It is believed that Abori ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cushion Plant
A cushion plant is a compact, low-growing, mat-forming plant that is found in alpine, subalpine, arctic, or subarctic environments around the world. The term "cushion" is usually applied to woody plants that grow as spreading mats, are limited in height above the ground (a few inches at most), have relatively large and deep tap roots, and have life histories adapted to slow growth in a nutrient-poor environment with delayed reproductivity and reproductive cycle adaptations. The plant form is an example of parallel or convergent evolution with species from many different plant families on different continents converging on the same evolutionary adaptations to endure the harsh environmental conditions.Went, F. W. (1971). Parallel evolution. ''Taxon'', 20(2/3): 197-226. Description Cushion plants form large, low-growing mats that can grow up to in diameter. The typical form is a compact mass of closely spaced stems with minimal apical dominance that terminate in individual ros ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Endemism
Endemism is the state of a species being found only in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found elsewhere. For example, the Cape sugarbird is found exclusively in southwestern South Africa and is therefore said to be ''endemic'' to that particular part of the world. An endemic species can also be referred to as an ''endemism'' or, in scientific literature, as an ''endemite''. Similarly, many species found in the Western ghats of India are examples of endemism. Endemism is an important concept in conservation biology for measuring biodiversity in a particular place and evaluating the risk of extinction for species. Endemism is also of interest in evolutionary biology, because it provides clues about how changes in the environment cause species to undergo range shifts (potentially expanding their range into a larger area or b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
