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Cladonia Mongkolsukii
''Cladonia mongkolsukii'' is a species of fruticose lichen in the family Cladoniaceae. Described as new to science in 2011, it is found in lower-elevation montane scrub forests of northeast Thailand and in Sri Lanka. The specific epithet honors Pachara Mongolsuk, a Thai lichenologist. Taxonomy ''Cladonia mongkolsukii'' was first described by Sittiporn Parnmen and Teuvo Ahti. The species name honours Thai lichenologist Pachara Mongolsuk. The type specimen was collected by the first author in Phu Hin Rong Kla National Park, Pitsanulok Province, Thailand, at an elevation of . Phylogenetic analysis A molecular phylogenetic analysis based on internal transcribed spacer sequence data placed ''Cladonia mongkolsukii'' near ''Cladonia singhii''. This clade also includes ''Cladonia fimbriata'', ''Cladonia gracilis'', and ''Cladonia ochrochlora''. The latter three species were grouped into the "supergroup" ''Cladonia'' by Stenroos et al. (2002). Description The of ''Cladonia mon ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Teuvo Ahti
Teuvo ("Ted") Tapio Ahti (born 1934) is a Finnish botanist and lichenologist. He has had a long career at the University of Helsinki that started in 1963, and then following his retirement in 1997, at the Botanical Museum of the Finnish Museum of Natural History. Known as a specialist of the lichen family Cladoniaceae, Ahti has published more than 280 scientific publications. A ''Festschrift'' was dedicated to him in 1994, and in 2000 he was awarded the prestigious Acharius Medal for lifetime contributions to lichenology. Education and career Ahti started developing an interest in botany at the age of 15, when he worked on a class project involving collecting 100 species of plants. His attention turned to lichens when a classmate who had worked for Veli Räsänen pointed them out during a birdwatching excursion in Helsinki. His interest was further fuelled when a couple of years later, he had to pass a test on identification of forest floor lichens and bryophytes as part of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Supergroup (biology)
A supergroup, in evolutionary biology, is a large group of organisms that share one common ancestor and have important defining characteristics. It is an informal, mostly arbitrary rank in biological taxonomy that is often greater than phylum or kingdom, although some supergroups are also treated as phyla. Eukaryotic supergroups Since the decade of 2000's, the eukaryotic tree of life (abbreviated as eToL) has been divided into 5–8 major groupings called 'supergroups'. These groupings were established after the idea that only monophyletic groups should be accepted as ranks, as an alternative to the use of paraphyletic kingdom Protista. In the early days of the eToL six traditional supergroups were considered: Amoebozoa, Opisthokonta, "Excavata", Archaeplastida, "Chromalveolata" and Rhizaria. Since then, the eToL has been rearranged profoundly, and most of these groups were found as paraphyletic or lacked defining morphological characteristics that unite their members, which mak ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Indian Subcontinent
The Indian subcontinent is a list of the physiographic regions of the world, physiographical region in United Nations geoscheme for Asia#Southern Asia, Southern Asia. It is situated on the Indian Plate, projecting southwards into the Indian Ocean from the Himalayas. Geopolitically, it includes the countries of Bangladesh, Bhutan, India, Maldives, Nepal, Pakistan, and Sri Lanka."Indian subcontinent". ''Oxford Dictionary of English, New Oxford Dictionary of English'' () New York: Oxford University Press, 2001; p. 929: "the part of Asia south of the Himalayas which forms a peninsula extending into the Indian Ocean, between the Arabian Sea and the Bay of Bengal. Historically forming the whole territory of Greater India, the region is now divided into three countries named Bangladesh, India and Pakistan." The terms ''Indian subcontinent'' and ''South Asia'' are often used interchangeably to denote the region, although the geopolitical term of South Asia frequently includes Afghanist ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Isan
Northeast Thailand or Isan (Isan/ th, อีสาน, ; lo, ອີສານ; also written as Isaan, Isarn, Issarn, Issan, Esan, or Esarn; from Pali ''īsānna'' or Sanskrit ईशान्य ''īśānya'' "northeast") consists of 20 provinces in the northeastern region of Thailand. Isan is Thailand's largest region, located on the Khorat Plateau, bordered by the Mekong River (along the Laos–Thailand border) to the north and east, by Cambodia to the southeast and the Sankamphaeng Range south of Nakhon Ratchasima. To the west it is separated from northern and central Thailand by the Phetchabun Mountains. Isan covers making it about half the size of Germany and roughly the size of England and Wales. The total forest area is or 15 percent of Isan's area. Since the beginning of the 20th century, northeastern Thailand has been generally known as ''Isan'', while in official contexts the term ''phak tawan-ok-chiang-nuea'' (; 'northeastern region') may be used. The majority p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Montane
Montane ecosystems are found on the slopes of mountains. The alpine climate in these regions strongly affects the ecosystem because temperatures fall as elevation increases, causing the ecosystem to stratify. This stratification is a crucial factor in shaping plant community, biodiversity, metabolic processes and ecosystem dynamics for montane ecosystems. Dense montane forests are common at moderate elevations, due to moderate temperatures and high rainfall. At higher elevations, the climate is harsher, with lower temperatures and higher winds, preventing the growth of trees and causing the plant community to transition to montane grasslands, shrublands or alpine tundra. Due to the unique climate conditions of montane ecosystems, they contain increased numbers of endemic species. Montane ecosystems also exhibit variation in ecosystem services, which include carbon storage and water supply. Life zones As elevation increases, the climate becomes cooler, due to a decrease in a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cladonia Awasthiana
''Cladonia'' is a genus of moss-like lichens in the family Cladoniaceae. They are the primary food source for reindeer/caribou. ''Cladonia'' species are of economic importance to reindeer-herders, such as the Sami in Scandinavia or the Nenets in Russia. Antibiotic compounds are extracted from some species to create antibiotic cream. The light green species ''Cladonia stellaris'' is used in flower decorations. Although the phylogeny of the genus ''Cladonia'' is still under investigation, two main morphological groups are commonly differentiated by taxonomists: the ''Cladonia'' morpho-type and the ''Cladina'' morpho-type. The ''Cladonia'' morpho-type has many more species, and is generally described as a group of squamulose (grow from squamules), cup-bearing lichens. The ''Cladina'' morpho-types are often referred to as forage lichens, mat-forming lichens, or reindeer lichens (due to their importance as caribou winter forage). ''Cladonia perforata'' ("perforate cladonia") is one ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lichen Product
Lichen products, also known as lichen substances, are organic compounds produced by a lichen. Specifically, they are secondary metabolites. Lichen products are represented in several different chemical classes, including terpenoids, orcinol derivatives, chromones, xanthones, depsides, and depsidones. Over 800 lichen products of known chemical structure have been reported in the scientific literature, and most of these compound are exclusively found in lichens. Examples of lichen products include usnic acid (a dibenzofuran), atranorin (a depside), lichexanthone (a xanthone), salazinic acid (a depsidone), and isolichenan, an α-glucan. Many lichen products have biological activity, and research into these effects is ongoing. Lichen products accumulate on the outer walls of the fungal hyphae, and are quite stable. Crystal deposits can be visualised using scanning electron microscopy. For this reason, even very old herbarium specimens can be analysed. The amount of lichen products i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Secondary Metabolism
Secondary metabolism (also called specialized metabolism) is a term for pathways and small molecule products of metabolism that are involved in ecological interactions, but are not absolutely required for the survival of the organism. These molecules are sometimes produced by specialized cells, such as laticifers in plants. Secondary metabolites commonly mediate antagonistic interactions, such as competition and predation, as well as mutualistic ones such as pollination and resource mutualisms. Examples of secondary metabolites include antibiotics, pigments and scents. The opposite of secondary metabolites are primary metabolites, which are considered to be essential to the normal growth or development of an organism. Secondary metabolites are produced by many microbes, plants, fungi and animals, usually living in crowded habitats, where chemical defense represents a better option than physical escape. It is very hard to distinguish primary and secondary metabolites due to often ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Micrometre
The micrometre ( international spelling as used by the International Bureau of Weights and Measures; SI symbol: μm) or micrometer (American spelling), also commonly known as a micron, is a unit of length in the International System of Units (SI) equalling (SI standard prefix "micro-" = ); that is, one millionth of a metre (or one thousandth of a millimetre, , or about ). The nearest smaller common SI unit is the nanometre, equivalent to one thousandth of a micrometre, one millionth of a millimetre or one billionth of a metre (). The micrometre is a common unit of measurement for wavelengths of infrared radiation as well as sizes of biological cells and bacteria, and for grading wool by the diameter of the fibres. The width of a single human hair ranges from approximately 20 to . The longest human chromosome, chromosome 1, is approximately in length. Examples Between 1 μm and 10 μm: * 1–10 μm – length of a typical bacterium * 3–8 μm – width of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ellipsoid
An ellipsoid is a surface that may be obtained from a sphere by deforming it by means of directional scalings, or more generally, of an affine transformation. An ellipsoid is a quadric surface; that is, a surface that may be defined as the zero set of a polynomial of degree two in three variables. Among quadric surfaces, an ellipsoid is characterized by either of the two following properties. Every planar cross section is either an ellipse, or is empty, or is reduced to a single point (this explains the name, meaning "ellipse-like"). It is bounded, which means that it may be enclosed in a sufficiently large sphere. An ellipsoid has three pairwise perpendicular axes of symmetry which intersect at a center of symmetry, called the center of the ellipsoid. The line segments that are delimited on the axes of symmetry by the ellipsoid are called the ''principal axes'', or simply axes of the ellipsoid. If the three axes have different lengths, the figure is a triaxial ellipsoid (r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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