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Astrothelium Conjugatum
''Astrothelium conjugatum'' is a species of corticolous (bark-dwelling) crustose lichen in the family Trypetheliaceae, first described in 2016. It is known to occur in Sri Lanka. Taxonomy The species was formally described in 2016 by lichenologists Gothamie Weerakoon and André Aptroot. The type specimen was collected in Rilhena, Sri Lanka. Description ''Astrothelium conjugatum'' is characterized by its ascomata, which are and arranged with 2–8 chambers joined with eccentric, fused ostioles. Typically, 3–10 fused ascomata are grouped within one . The pseudostromata are about 1–5 mm in diameter, to prominent, with an irregularly to linear outline. They are completely covered by a thallus layer that is thick and opaque at the sides. The top of the pseudostromata can be similar in appearance or thinner and translucent, in which case the black ascoma wall is visible through it. The thallus itself is , pale yellowish brown, rather smooth, covering areas of up to in ...
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Gothamie Weerakoon
Gothamie Weerakoon ( si, ගෝතමී වීරකෝන්) is a Sri Lankan-based botanist, lichenologist and environmentalist. Early life and education After completing her primary education at the Devi Balika Vidyalaya in Colombo, she attended the University of Colombo, completing her PhD in 2013 at the Sri Jayawardenepura University. She emerged as the most active Sri Lankan lichen researcher. Career She has conducted research on South Asian lichens, discovering over 100 new species endemic to Sri Lanka. Some of the species she has discovered include ''Heterodermia queesnberryi'' and ''Polymeridium fernandoi''. In 2015, she wrote ''Fascinating Lichens of Sri Lanka'', which provides facts about lichen species endemic to Sri Lanka. She currently works as the senior curator of Lichens and Slime Moulds at the Natural History Museum of London and also with tea brand, Dilmah. Awards and recognition She is the first South Asian woman scientist to hold the Annual Grante ...
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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 � ...
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Lichens Of Sri Lanka
A lichen ( , ) is a composite organism that arises from algae or cyanobacteria living among filaments of multiple fungi species in a mutualistic relationship.Introduction to Lichens – An Alliance between Kingdoms
. University of California Museum of Paleontology.
Lichens have properties different from those of their component organisms. They come in many colors, sizes, and forms and are sometimes plant-like, but are not s. They may have tiny, leafless branches (); flat leaf-like structures (
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Lichens Described In 2016
A lichen ( , ) is a composite organism that arises from algae or cyanobacteria living among filaments of multiple fungi species in a mutualistic relationship.Introduction to Lichens – An Alliance between Kingdoms
. University of California Museum of Paleontology.
Lichens have properties different from those of their component organisms. They come in many colors, sizes, and forms and are sometimes plant-like, but are not s. They may have tiny, leafless branches (); flat leaf-like structures (

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Astrothelium
''Astrothelium'' is a genus of corticolous (bark-dwelling) lichens in the family Trypetheliaceae. The genus was circumscribed in 1824 by German botanist Franz Gerhard Eschweiler, with ''Astrothelium conicum'' assigned as the type species. Species , Species Fungorum accepts 241 species in ''Astrothelium''. *'' Astrothelium aenascens'' *''Astrothelium aeneoides'' – Brazil *''Astrothelium aeneum'' *''Astrothelium alboverrucoides'' *''Astrothelium alboverrucum'' *''Astrothelium amazonum'' *''Astrothelium ambiguum'' *''Astrothelium amylosporum'' – Bolivia *''Astrothelium andamanicum'' *''Astrothelium annulare'' *''Astrothelium astrolucidum'' – Brazil *''Astrothelium aurantiacocinereum'' *''Astrothelium aurantiacum'' *''Astrothelium auratum'' *''Astrothelium aureomaculatum'' *''Astrothelium basilicum'' *''Astrothelium bicolor'' *''Astrothelium bivelum'' – Brazil *''Astrothelium buckii'' *'' Astrothelium bullatothallinum'' – Venezuela *''Astrothelium bul ...
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Tropical Rainforest
Tropical rainforests are rainforests that occur in areas of tropical rainforest climate in which there is no dry season – all months have an average precipitation of at least 60 mm – and may also be referred to as ''lowland equatorial evergreen rainforest''. True rainforests are typically found between 10 degrees north and south of the equator (see map); they are a sub-set of the tropical forest biome that occurs roughly within the 28-degree latitudes (in the equatorial zone between the Tropic of Cancer and Tropic of Capricorn). Within the World Wildlife Fund's biome classification, tropical rainforests are a type of tropical moist broadleaf forest (or tropical wet forest) that also includes the more extensive seasonal tropical forests. Overview Tropical rainforests are characterized by two words: hot and wet. Mean monthly temperatures exceed during all months of the year. Average annual rainfall is no less than and can exceed although it typically lies betwee ...
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Astrothelium Straminicolor
''Astrothelium'' is a genus of corticolous lichen, corticolous (bark-dwelling) lichens in the family Trypetheliaceae. The genus was circumscription (taxonomy), circumscribed in 1824 by German botanist Franz Gerhard Eschweiler, with ''Astrothelium conicum'' assigned as the type species. Species , Species Fungorum accepts 241 species in ''Astrothelium''. *''Astrothelium aenascens'' *''Astrothelium aeneoides'' – Brazil *''Astrothelium aeneum'' *''Astrothelium alboverrucoides'' *''Astrothelium alboverrucum'' *''Astrothelium amazonum'' *''Astrothelium ambiguum'' *''Astrothelium amylosporum'' – Bolivia *''Astrothelium andamanicum'' *''Astrothelium annulare'' *''Astrothelium astrolucidum'' – Brazil *''Astrothelium aurantiacocinereum'' *''Astrothelium aurantiacum'' *''Astrothelium auratum'' *''Astrothelium aureomaculatum'' *''Astrothelium basilicum'' *''Astrothelium bicolor'' *''Astrothelium bivelum'' – Brazil *''Astrothelium buckii'' *''Astrothelium bullatothal ...
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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 ...
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Thin-layer Chromatography
Thin-layer chromatography (TLC) is a chromatography technique used to separate non-volatile mixtures. Thin-layer chromatography is performed on a sheet of an inert substrate such as glass, plastic, or aluminium foil, which is coated with a thin layer of adsorbent material, usually silica gel, aluminium oxide (alumina), or cellulose. This layer of adsorbent is known as the stationary phase. After the sample has been applied on the plate, a solvent or solvent mixture (known as the mobile phase) is drawn up the plate via capillary action. Because different analytes ascend the TLC plate at different rates, separation is achieved. It may be performed on the analytical scale as a means of monitoring the progress of a reaction, or on the preparative scale to purify small amounts of a compound. TLC is an analytical tool widely used because of its simplicity, relative low cost, high sensitivity, and speed of separation. TLC functions on the same principle as all chromatography: a ...
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Spot Test (lichen)
A spot test in lichenology is a spot analysis used to help identify lichens. It is performed by placing a drop of a chemical on different parts of the lichen and noting the colour change (or lack thereof) associated with application of the chemical. The tests are routinely encountered in dichotomous keys for lichen species, and they take advantage of the wide array of lichen products produced by lichens and their uniqueness among taxa. As such, spot tests reveal the presence or absence of chemicals in various parts of a lichen. They were first proposed by the botanist William Nylander in 1866. Three common spot tests use either 10% aqueous KOH solution (K test), saturated aqueous solution of bleaching powder or calcium hypochlorite (C test), or 5% alcoholic ''p''-phenylenediamine solution (P test). The colour changes occur due to presence of particular secondary metabolites in the lichen. There are several other less frequently used spot tests of more limited use that are ...
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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 ellipsoi ...
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