|
Allocetraria Madreporiformis
''Allocetraria'' is a genus of lichenized fungi in the family Parmeliaceae. It consists of 12 species, with a center of distribution in China. Systematics The genus was circumscribed by Syo Kurokawa and Ming-Jou Lai in 1991, with three species: both '' A. ambigua'' and the type species '' A. stracheyi'' recombined from different genera, and a newly described species, '' A. isidiigera''. Sunsequent molecular phylogenetic analyses showed that ''Allocetraria'' forms a monophyletic group within the cetrarioid clade in the family Parmeliaceae. In 2017, Divakar and colleagues used a then-recently developed "temporal phylogenetic" approach to identify temporal bands for specific taxonomic ranks in the family Parmeliaceae, suggesting that groups of species that diverged within the time window of 29.45–32.55 million years ago represent genera. They proposed to synonymize ''Allocetraria'' (and several other genera) with '' Cetraria'', because the former group of sp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Allocetraria Madreporiformis
''Allocetraria'' is a genus of lichenized fungi in the family Parmeliaceae. It consists of 12 species, with a center of distribution in China. Systematics The genus was circumscribed by Syo Kurokawa and Ming-Jou Lai in 1991, with three species: both '' A. ambigua'' and the type species '' A. stracheyi'' recombined from different genera, and a newly described species, '' A. isidiigera''. Sunsequent molecular phylogenetic analyses showed that ''Allocetraria'' forms a monophyletic group within the cetrarioid clade in the family Parmeliaceae. In 2017, Divakar and colleagues used a then-recently developed "temporal phylogenetic" approach to identify temporal bands for specific taxonomic ranks in the family Parmeliaceae, suggesting that groups of species that diverged within the time window of 29.45–32.55 million years ago represent genera. They proposed to synonymize ''Allocetraria'' (and several other genera) with '' Cetraria'', because the former group of sp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Evolutionary Divergence
Divergent evolution or divergent selection is the accumulation of differences between closely related populations within a species, leading to speciation. Divergent evolution is typically exhibited when two populations become separated by a geographic barrier (such as in allopatric or peripatric speciation) and experience different selective pressures that drive adaptations to their new environment. After many generations and continual evolution, the populations become less able to interbreed with one another. The American naturalist J. T. Gulick (1832–1923) was the first to use the term "divergent evolution", with its use becoming widespread in modern evolutionary literature. Classic examples of divergence in nature are the adaptive radiation of the finches of the Galapagos or the coloration differences in populations of a species that live in different habitats such as with pocket mice and fence lizards. The term can also be applied in molecular evolution, such as to pr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Allocetraria Capitata
''Allocetraria'' is a genus of lichenized fungi in the family Parmeliaceae. It consists of 12 species, with a center of distribution in China. Systematics The genus was circumscribed by Syo Kurokawa and Ming-Jou Lai in 1991, with three species: both '' A. ambigua'' and the type species '' A. stracheyi'' recombined from different genera, and a newly described species, '' A. isidiigera''. Sunsequent molecular phylogenetic analyses showed that ''Allocetraria'' forms a monophyletic group within the cetrarioid clade in the family Parmeliaceae. In 2017, Divakar and colleagues used a then-recently developed "temporal phylogenetic" approach to identify temporal bands for specific taxonomic ranks in the family Parmeliaceae, suggesting that groups of species that diverged within the time window of 29.45–32.55 million years ago represent genera. They proposed to synonymize ''Allocetraria'' (and several other genera) with '' Cetraria'', because the former group of sp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Atranorin
Atranorin is a chemical substance produced by some species of lichen. It is a secondary metabolite belonging to a group of compounds known as depsides. Atranorin has analgesic, anti-inflammatory, antibacterial, antifungal, cytotoxic, antioxidant, antiviral, and immunomodulatory properties. In rare cases, people can react allergic Allergies, also known as allergic diseases, refer a number of conditions caused by the hypersensitivity of the immune system to typically harmless substances in the environment. These diseases include hay fever, food allergies, atopic derma ... to atranorin. References Further reading * * * * Polyphenols Lichen products {{organic-compound-stub ... [...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 protect ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ascospore
An ascus (; ) is the sexual spore-bearing cell produced in ascomycete fungi. Each ascus usually contains eight ascospores (or octad), produced by meiosis followed, in most species, by a mitotic cell division. However, asci in some genera or species can occur in numbers of one (e.g. ''Monosporascus cannonballus''), two, four, or multiples of four. In a few cases, the ascospores can bud off conidia that may fill the asci (e.g. ''Tympanis'') with hundreds of conidia, or the ascospores may fragment, e.g. some ''Cordyceps'', also filling the asci with smaller cells. Ascospores are nonmotile, usually single celled, but not infrequently may be coenocytic (lacking a septum), and in some cases coenocytic in multiple planes. Mitotic divisions within the developing spores populate each resulting cell in septate ascospores with nuclei. The term ocular chamber, or oculus, refers to the epiplasm (the portion of cytoplasm not used in ascospore formation) that is surrounded by the "bourrelet ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ascus
An ascus (; ) is the sexual spore-bearing cell produced in ascomycete fungi. Each ascus usually contains eight ascospores (or octad), produced by meiosis followed, in most species, by a mitotic cell division. However, asci in some genera or species can occur in numbers of one (e.g. ''Monosporascus cannonballus''), two, four, or multiples of four. In a few cases, the ascospores can bud off conidia that may fill the asci (e.g. ''Tympanis'') with hundreds of conidia, or the ascospores may fragment, e.g. some ''Cordyceps'', also filling the asci with smaller cells. Ascospores are nonmotile, usually single celled, but not infrequently may be coenocytic (lacking a septum), and in some cases coenocytic in multiple planes. Mitotic divisions within the developing spores populate each resulting cell in septate ascospores with nuclei. The term ocular chamber, or oculus, refers to the epiplasm (the portion of cytoplasm not used in ascospore formation) that is surrounded by the "bourrelet ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cortex (botany)
In botany, a cortex is an outer layer of a stem or root in a vascular plant, lying below the epidermis but outside of the vascular bundles. The cortex is composed mostly of large thin-walled parenchyma cells of the ground tissue system and shows little to no structural differentiation. The outer cortical cells often acquire irregularly thickened cell walls, and are called collenchyma cells. Plants Stems and branches In the three dimensional structure of herbaceous stems, the epidermis, cortex and vascular cambium form concentric cylinders around the inner cylindrical core of pith. Some of the outer cortical cells may contain chloroplasts, giving them a green color. They can therefore produce simple carbohydrates through photosynthesis. In woody plants, the cortex is located between the periderm (bark) and the vascular tissue (phloem, in particular). It is responsible for the transportation of materials into the central cylinder of the root through diffusion and may als ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plectenchyma
Plectenchyma (from Greek πλέκω ''pleko'' 'I weave' and ἔγχυμα ''enchyma'' 'infusion', i.e., 'a woven tissue') is the general term employed to designate all types of fungal tissues. The two most common types of tissues are prosenchyma and pseudoparenchyma. The hyphae A hypha (; ) is a long, branching, filamentous structure of a fungus, oomycete, or actinobacterium. In most fungi, hyphae are the main mode of vegetative growth, and are collectively called a mycelium. Structure A hypha consists of one or ... specifically become fused together. Notes Fungal morphology and anatomy {{mycology-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
