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Pteris Adscensionis
''Pteris adscensionis'' is a fern species in the subfamily Pteridoideae of the family Pteridaceae. It is endemic to Ascension Island, and there are thought to be fewer than 500 individuals left in the wild. Its natural habitat In ecology, habitat refers to the array of resources, biotic factors that are present in an area, such as to support the survival and reproduction of a particular species. A species' habitat can be seen as the physical manifestation of its ... has been severely reduced due to the large number of species introduced to the island when it was first settled in the 18th century. References adscensionis Flora of Ascension Island Critically endangered plants Taxonomy articles created by Polbot Taxa named by Olof Swartz {{Pteridaceae-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Olof Swartz
Olof Peter Swartz (21 September 1760 – 19 September 1818) was a Swedish botanist and taxonomist. He is best known for his taxonomic work and studies into pteridophytes, but also studied orchids, mosses and lichens. Biography Olof Swartz attended the University of Uppsala where he studied under Carl Linnaeus the Younger (1741–1783) and received his doctorate in 1781. He first traveled in 1780 to Sápmi (area), Lapland in the company of several other botanists. In 1783 he sailed for North America and the West Indies, primarily in the area of Jamaica and Hispaniola, to collect botanical specimens. His botanical collection, of an impressive 6000 specimens, is now held by the Swedish Museum of Natural History, as part of the Regnellian herbarium. By 1786 he left for London to prepare his collection. There he met naturalist Joseph Banks (1743–1820), who was impressed with his knowledge of Botany. He was offered a position with the British East India Company as a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fern
The ferns (Polypodiopsida or Polypodiophyta) are a group of vascular plants (plants with xylem and phloem) that reproduce via spores and have neither seeds nor flowers. They differ from mosses by being vascular, i.e., having specialized tissues that conduct water and nutrients, and in having life cycles in which the branched sporophyte is the dominant phase. Ferns have complex leaf, leaves called megaphylls that are more complex than the microphylls of clubmosses. Most ferns are leptosporangiate ferns. They produce coiled Fiddlehead fern, fiddleheads that uncoil and expand into fronds. The group includes about 10,560 known extant species. Ferns are defined here in the broad sense, being all of the Polypodiopsida, comprising both the leptosporangiate (Polypodiidae (plant), Polypodiidae) and eusporangiate ferns, the latter group including horsetails, Psilotaceae, whisk ferns, marattioid ferns, and ophioglossoid ferns. The fern crown group, consisting of the leptosporangiates and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pteridoideae
''Pteridoideae'' is one of the five subfamilies of the fern family Pteridaceae. This subfamily contains about 14 genera and around 400 species. Taxonomy Phylogeny The following diagram shows a likely phylogenic relationship between Pteridoideae and the other the Pteridaceae subfamilies. The cladogram below shows one hypothesis for the evolutionary relationships among the genera of the Pteridoideae, based on a maximum likelihood analysis using six plastid markers. The authors of the study identified four major clades. The ''Pteris'' and JAPSTT clades are found worldwide; the GAPCC clade is pantropical; and the ''Actiniopteris''+''Onychium'' clade is restricted to the Old World. Genera The Pteridophyte Phylogeny Group classification of 2016 (PPG I) recognized 13 genera. Shortly afterwards, the genus ''Gastoniella'' was created for three species formerly placed in ''Anogramma'' which a Molecular phylogenetics, molecular phylogenetic analysis had shown to be distinct. * ''Actini ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pteridaceae
Pteridaceae is a family of ferns in the order Polypodiales, including some 1150 known species in ca 45 genera (depending on taxonomic opinions), divided over five subfamilies. The family includes four groups of genera that are sometimes recognized as separate families: the adiantoid, cheilanthoid, pteridoid, and hemionitidoid ferns. Relationships among these groups remain unclear, and although some recent genetic analyses of the Pteridales suggest that neither the family Pteridaceae nor the major groups within it are all monophyletic, as yet these analyses are insufficiently comprehensive and robust to provide good support for a revision of the order at the family level. Description Members of Pteridaceae have creeping or erect rhizomes. The leaves are almost always compound and have linear sori that are typically on the margins of the leaves and lack a true indusium, typically being protected by a false indusium formed from the reflexed margin of the leaf. Taxonomy Tra ... [...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] |
Ascension Island
Ascension Island is an isolated volcanic island, 7°56′ south of the Equator in the Atlantic Ocean, South Atlantic Ocean. It is about from the coast of Africa and from the coast of South America. It is governed as part of the British Overseas Territories, British Overseas Territory of Saint Helena, Ascension and Tristan da Cunha, of which the main island, Saint Helena, is around to the southeast. The territory also includes the sparsely populated Tristan da Cunha archipelago, to the south, about halfway to the Antarctic Circle. The discovery of Ascension by Joao da Nova in 1501 was described by two Portuguese chroniclers who probably misnamed it as Conception Island. The popular idea that Ascension was rediscovered by Afonso de Albuquerque in 1503 is probably wrong, Ascension having been long confused with Trindade and Martim Vaz, Trindade. Ascension Island was garrisoned by the British Admiralty from 22 October 1815 to 1922 and was an important refueling stop for ships a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Habitat
In ecology, habitat refers to the array of resources, biotic factors that are present in an area, such as to support the survival and reproduction of a particular species. A species' habitat can be seen as the physical manifestation of its ecological niche. Thus "habitat" is a species-specific term, fundamentally different from concepts such as Biophysical environment, environment or vegetation assemblages, for which the term "habitat-type" is more appropriate. The physical factors may include (for example): soil, moisture, range of temperature, and Luminous intensity, light intensity. Biotic index, Biotic factors include the availability of food and the presence or absence of Predation, predators. Every species has particular habitat requirements, habitat generalist species are able to thrive in a wide array of environmental conditions while habitat specialist species require a very limited set of factors to survive. The habitat of a species is not necessarily found in a ge ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phytotaxa
''Phytotaxa'' is a peer-reviewed scientific journal for rapid publication on any aspect of systematic botany. It publishes on a wide range of subjects, but focuses on new species, monographs, floras, revisions, reviews, and typification issues. ''Phytotaxa'' covers all plant groups covered by the International Code of Nomenclature for algae, fungi, and plants, including diatoms, fungi, algae, lichens, mosses, hornworts, liverworts, and vascular plants), both living and fossil. The journal was established in 2009 by Maarten Christenhusz and the first issue appeared in October 2009. Authors have the option to publish open access. Abstracting and indexing The journal is abstracted and indexed in Science Citation Index Expanded, Current Contents/Agriculture, Biology & Environmental Sciences, and BIOSIS Previews. See also * Zootaxa ''Zootaxa'' is a peer-reviewed scientific mega journal for animal taxonomists. It is published by Magnolia Press (Auckland, New Zealand). The jou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pteris
''Pteris'' (brake) is a genus of about 300 species of ferns in the subfamily Pteridoideae of the family Pteridaceae. They are native to tropical and subtropical regions, southward to New Zealand, Australia, and South Africa, north to Japan and North America. 78 species (35 endemic) are found in China. Some species of ''Pteris'' have considerable economic and ecological value, such as ''Pteris multifida'', ''Pteris ensiformis'', ''Pteris vittata'' can be used for ornamental purposes; as a hyperaccumulator, ''Pteris multifida'' and ''Pteris vittata'' can be used to control soil pollution. Many of them have linear frond segments, and some have sub-palmate division. Like other members of the Pteridaceae, the frond margin is reflexed over the marginal sorus, sori. The outermost layer is the single layered epidermis without stomata. The cortex is differentiated into outer and inner cortical region. The vascular cylinder is an wikt:amphiphloic, amphiphloic siphonostele. The term "brak ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flora Of Ascension Island
Flora (: floras or florae) is all the plant life present in a particular region or time, generally the naturally occurring ( indigenous) native plants. The corresponding term for animals is ''fauna'', and for fungi, it is '' funga''. Sometimes bacteria and fungi are also referred to as flora as in the terms ''gut flora'' or ''skin flora'' for purposes of specificity. Etymology The word "flora" comes from the Latin name of Flora, the goddess of plants, flowers, and fertility in Roman mythology. The technical term "flora" is then derived from a metonymy of this goddess at the end of the sixteenth century. It was first used in poetry to denote the natural vegetation of an area, but soon also assumed the meaning of a work cataloguing such vegetation. Moreover, "Flora" was used to refer to the flowers of an artificial garden in the seventeenth century. The distinction between vegetation (the general appearance of a community) and flora (the taxonomic composition of a community) wa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Taxonomy Articles Created By Polbot
280px, Generalized scheme of taxonomy Taxonomy is a practice and science concerned with classification or categorization. Typically, there are two parts to it: the development of an underlying scheme of classes (a taxonomy) and the allocation of things to the classes (classification). Originally, taxonomy referred only to the classification of organisms on the basis of shared characteristics. Today it also has a more general sense. It may refer to the classification of things or concepts, as well as to the principles underlying such work. Thus a taxonomy can be used to organize species, documents, videos or anything else. A taxonomy organizes taxonomic units known as "taxa" (singular "taxon"). Many are hierarchies. One function of a taxonomy is to help users more easily find what they are searching for. This may be effected in ways that include a library classification system and a search engine taxonomy. Etymology The word was coined in 1813 by the Swiss botanist A ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
