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Astrothelium Corallinum
''Astrothelium corallinum'' is a species of corticolous (bark-dwelling), crustose lichen in the family Trypetheliaceae. Found in Guyana, it was formally described as a new species in 2016 by André Aptroot. The type specimen was collected from Rain Mountain, southeast of the village in Paruima Mission ( Upper Mazaruni District) at an altitude of ; here, it was found growing on the smooth bark of trees in a rainforest Rainforests are characterized by a closed and continuous tree canopy, moisture-dependent vegetation, the presence of epiphytes and lianas and the absence of wildfire. Rainforest can be classified as tropical rainforest or temperate rainfores .... The lichen has a smooth, somewhat shiny thallus that covers areas of up to in diameter; the entire thallus is surrounded by a thin (0.3 mm) black line that is the prothallus. The whitish parts of the pseudostromata will fluoresce yellow when lit with a long-wavelength UV light; this is due to the presence ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
André Aptroot
André Aptroot (Heemskerk, 1961) is a Dutch mycologist and lichenologist. In 1993 he did his PhD at the University of Utrecht under the supervision of Robbert Gradstein (nl). His dissertation was titled "Systematic studies on pyrenocarpous lichens and related fungi". He specializes in fungi and lichens on which he has several hundreds of publications to his name. He has worked as curator at Centraalbureau voor Schimmelcultures (now Westerdijk Institute). Aptroot is the founder of the Consultancy for Bryology and Lichenology, which is located in Soest where there is a herbarium with a collection of lichens mainly from the Netherlands and the tropics. From 2008 he has been collection manager at Pinetum Blijdenstein (nl) in Hilversum. He is a member of the International Association for Lichenology and the American Bryological and Lichenological Society. He is a visiting professor at the Federal University of Mato Grosso do Sul in Campo Grande, Brazil. Because of Aptroot's bro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Prothallus
A prothallus, or prothallium, (from Latin ''pro'' = forwards and Greek ''θαλλος'' (''thallos'') = twig) is usually the gametophyte stage in the life of a fern or other pteridophyte. Occasionally the term is also used to describe the young gametophyte of a liverwort or peat moss as well. In lichens it refers to the region of the thallus that is free of algae. The prothallus develops from a germinating spore. It is a short-lived and inconspicuous heart-shaped structure typically 2–5 millimeters wide, with a number of rhizoids (root-like hairs) growing underneath, and the sex organs: archegonium (female) and antheridium (male). Appearance varies quite a lot between species. Some are green and conduct photosynthesis while others are colorless and nourish themselves underground as saprotrophs. Alternation of generations Spore-bearing plants, like all plants, go through a life-cycle of alternation of generations. The fully grown sporophyte, what is commonly referred to as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 ( |
Lichen Species
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 ( |
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 *'' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Astrothelium Ochroleucoides
''Astrothelium ochroleucoides'' is a species of corticolous (bark-dwelling) lichen in the family Trypetheliaceae. It is found in Brazil and Guyana. Taxonomy ''Astrothelium ochroleucoides'' was first described in 2016 by lichenologists André Aptroot and Marcela Cáceres. The type specimen was collected from Estação Ecológica de Cuniã (near Porto Velho, Rondônia), where it was growing on tree bark in primary rainforest. It is most similar to '' Astrothelium corallinum''; the main difference between the two species is the presence of lichexanthone on the thallus and in ''Astrothelium ochroleucoides''. Description The thallus of ''Astrothelium ochroleucoides'' is , smooth, somewhat shiny, and continuous, covering areas up to in diameter. It is olive-green, approximately 0.1 mm thick, and surrounded by a black prothallus line about 0.3 mm wide. This species does not induce gall formation on the host bark. Ascomata are spherical, measuring 0.4–0.6 m ... [...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] |
Lichexanthone
Lichexanthone is an organic compound in the structural class of chemicals known as xanthones. Lichexanthone was first isolated and identified by Japanese chemists from a species of leafy lichen in the 1940s. The compound is known to occur in many lichens, and it is important in the taxonomy of species in several genera, such as ''Pertusaria'' and ''Pyxine''. More than a dozen lichen species have a variation of the word lichexanthone incorporated as part of their binomial name. The presence of lichexanthone in lichens causes them to fluoresce a greenish-yellow colour under long-wavelength UV light; this feature is used to help identify some species. Lichexanthone is also found in several plants (many are from the families Annonaceae and Rutaceae), and some species of fungi that do not form lichens. In lichens, the biosynthesis of lichexanthone occurs through a set of enzymatic reactions that start with the molecule acetyl-CoA and sequentially add successive units, forming a longe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
UV Light
Ultraviolet (UV) is a form of electromagnetic radiation with wavelength from 10 nm (with a corresponding frequency around 30 PHz) to 400 nm (750 THz), shorter than that of visible light, but longer than X-rays. UV radiation is present in sunlight, and constitutes about 10% of the total electromagnetic radiation output from the Sun. It is also produced by electric arcs and specialized lights, such as mercury-vapor lamps, tanning lamps, and black lights. Although long-wavelength ultraviolet is not considered an ionizing radiation because its photons lack the energy to ionize atoms, it can cause chemical reactions and causes many substances to glow or fluoresce. Consequently, the chemical and biological effects of UV are greater than simple heating effects, and many practical applications of UV radiation derive from its interactions with organic molecules. Short-wave ultraviolet light damages DNA and sterilizes surfaces with which it comes into contact. For huma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fluoresce
Fluorescence is the emission of light by a substance that has absorbed light or other electromagnetic radiation. It is a form of luminescence. In most cases, the emitted light has a longer wavelength, and therefore a lower photon energy, than the absorbed radiation. A perceptible example of fluorescence occurs when the absorbed radiation is in the ultraviolet region of the electromagnetic spectrum (invisible to the human eye), while the emitted light is in the visible region; this gives the fluorescent substance a distinct color that can only be seen when the substance has been exposed to UV light. Fluorescent materials cease to glow nearly immediately when the radiation source stops, unlike phosphorescent materials, which continue to emit light for some time after. Fluorescence has many practical applications, including mineralogy, gemology, medicine, chemical sensors (fluorescence spectroscopy), fluorescent labelling, dyes, biological detectors, cosmic-ray detection, vacuu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thallus
Thallus (plural: thalli), from Latinized Greek (), meaning "a green shoot" or "twig", is the vegetative tissue of some organisms in diverse groups such as algae, fungi, some liverworts, lichens, and the Myxogastria. Many of these organisms were previously known as the thallophytes, a polyphyletic group of distantly related organisms. An organism or structure resembling a thallus is called thalloid, thallodal, thalliform, thalline, or thallose. A thallus usually names the entire body of a multicellular non-moving organism in which there is no organization of the tissues into organs. Even though thalli do not have organized and distinct parts (leaves, roots, and stems) as do the vascular plants, they may have analogous structures that resemble their vascular "equivalents". The analogous structures have similar function or macroscopic structure, but different microscopic structure; for example, no thallus has vascular tissue. In exceptional cases such as the Lemnoideae, where ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Corticolous Lichen
A corticolous lichen is a lichen that grows on bark.Alan Silverside's Lichen Glossary (a-f), Alan Silverside/ref> This is contrasted with lignicolous lichen, which grows on wood that has had the bark stripped from it,Alan Silverside's Lichen Glossary (g-o), Alan Silverside/ref> and saxicolous lichen, which grows on rock.Alan Silverside's Lichen Glossary (p-z), Alan Silverside/ref> Examples of corticolous lichens include the crustose lichen ''Graphis plumierae'', foliose lichen ''Melanohalea subolivacea'' and the fruticose ''Bryoria fuscescens ''Bryoria fuscescens'' is a species of lichen of the family Parmeliaceae. As of July 2021, its conservation status has not been estimated by the IUCN. In Iceland, where it grows as an epiphyte on downy birch stems and branches, it is classified ...''.Náttúrufræðistofnun Íslands celandic Institute of Natural History(1996). Válisti 1: Plöntur.' (in Icelandic) Reykjavík: Náttúrufræðistofnun Íslands. References Lichenolog ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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