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Ramalina Rigidella
''Ramalina rigidella'' is a species of saxicolous (rock-dwelling), fruticose lichen in the family Ramalinaceae. It is found in the remote tropical island of Saint Helena, where it occurs on boulders and cliffs throughout the island. It was formally described as a new species in 2008 by Dutch lichenologist André Aptroot. The type specimen was collected by the author on the north slope of Dry Gut on Prosperous Bay Plain at an elevation of ; there, it was found growing on basalt. The fruticose thallus of the lichen, initially shrubby, become as it ages, reaching lengths of up to , although typically it is smaller, up to about . Thin-layer chromatography shows that the species contains usnic acid Usnic acid is a naturally occurring dibenzofuran derivative found in several lichen species with the formula C18H16O7. It was first isolated by German scientist W. Knop in 1844 and first synthesized between 1933-1937 by Curd and Robertson. Usnic a ..., norstictic acid, and conno ... [...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] |
Usnic Acid
Usnic acid is a naturally occurring dibenzofuran derivative found in several lichen species with the formula C18H16O7. It was first isolated by German scientist W. Knop in 1844 and first synthesized between 1933-1937 by Curd and Robertson. Usnic acid was identified in many genera of lichens including ''Usnea'', '' Cladonia'', ''Hypotrachyna'', ''Lecanora'', ''Ramalina'', '' Evernia'', ''Parmelia'' and '' Alectoria''. Although it is generally believed that usnic acid is exclusively restricted to lichens, in a few unconfirmed isolated cases the compound was found in kombucha tea and non-lichenized ascomycetes. At normal conditions, usnic acid is a bitter, yellow, solid substance. It is known to occur in nature in both the d- and l-forms as well as a racemic mixture. Salts of usnic acid are called usnates (e.g. copper usnate). Biological role in lichens Usnic acid is a secondary metabolite in lichens whose role has not been completely elucidated. It is believed that usnic acid prote ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lichens Described In 2008
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 ( [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 ( |
Ramalina
''Ramalina'' is a genus of greenish fruticose lichens that grow in the form of flattened, strap-like branches. Members of the genus are commonly called strap lichensField Guide to California Lichens, Stephen Sharnoff, Yale University Press, 2014, or cartilage lichens. Apothecia are lecanorine. Lichen spot tests on the cortex are K−, C−, KC+ dark yellow, and P−. It is in the Ramalinaceae and in the suborder Lecanorineae. Distribution The genus has a widespread distribution. A 2008 estimate placed more than 240 species in ''Ramalina''. Species *'' R. ailaoshanensis'' – China *'' R. alisiosae'' – Canary Islands *'' R. americana'' – North America *'' R. andina'' – Venezuela *'' R. arabum'' *'' R. arsenii'' – Europe *'' R. azorica'' – Azores *'' R. australiensis'' *'' R. banzarensis'' *'' R. breviuscula'' *'' R. caespitella'' – Australia *'' R. calcarata'' – East Africa *'' R. calicaris'' *'' R. canalicularis'' *'' R. canariensis'' *'' R. c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Medulla (lichenology)
The medulla is a horizontal layer within a lichen thallus. It is a loosely arranged layer of interlaced hyphae below the upper cortex and photobiont A lichen ( , ) is a composite organism that arises from algae or cyanobacteria living among filaments of multiple fungi species in a mutualistic relationship.Galloway, D.J. (1992). Flora of Australia - ''Lichen Glossary'' The medulla generally has a cottony appearance. It is the widest layer of a heteromerous lichen thallus. References Fungal morphology and anatomy Lichenology {{lichen-stub ...[...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Photobiont
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 ( |
Norstictic Acid
Norstictic acid is a depsidone produced as a secondary metabolites in lichen A lichen ( , ) is a composite organism that arises from algae or cyanobacteria living among filaments of multiple fungi species in a mutualistic relationship.Lactones Phenols Lichen products Heterocyclic compounds with 4 rings {{lichen-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 com ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Saxicolous Lichen
A saxicolous lichen is a lichen that grows on rock. The prefix "sax" from the Latin means "rock" or "stone". Characteristics Saxicolous lichens exhibit very slow growth rates. They may develop on rock substrates for long periods of time, given the absence of external disturbances. The importance of the mineral composition of the rock substrate, as well as the elemental geochemistry Geochemistry is the science that uses the tools and principles of chemistry to explain the mechanisms behind major geological systems such as the Earth's crust and its oceans. The realm of geochemistry extends beyond the Earth, encompassing the e ... is also important to the distribution of saxicolous lichens, but the relationship between the substrate influence on lichens, either chemical or textural, is still obscure. Communities of saxicolous lichens are often species-rich in terms of number. References Lichenology {{lichen-stub ... [...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] |
