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Herpothallon
''Herpothallon'' is a genus of crustose lichens in the family Arthoniaceae. It has about 50 species. Taxonomy The genus was circumscribed in 1930 by German lichenologist Friedrich Tobler, with ''Herpothallon sanguineum'' assigned as the type species. Tobler erroneously believed that the fungus was a member of the Basidiomycota. After it was recognized as an ascolichen, it was referred to either ''Chiodecton'' (family Roccellaceae) or ''Cryptothecia'' (family Arthoniaceae). In 2009, ''Herpothallon'' was resurrected following a publication by André Aptroot, Göran Thor, Robert Lücking, and John Elix, in which they recognized 29 species worldwide. The type species is now known as ''Herpothallon rubrocinctum'', or in the vernacular as the "Christmas lichen". Description ''Herpothallon'' is characterized by the byssoid (a wispy or cottony texture) prothallus (i.e., the first purely fungal layer upon which an algae-containing thallus develops) and hypothallus (i.e., a growth of u ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Herpothallon Rubrocinctum
''Herpothallon'' is a genus of crustose lichens in the family Arthoniaceae. It has about 50 species. Taxonomy The genus was circumscription (taxonomy), circumscribed in 1930 by German lichenologist Friedrich Tobler, with ''Herpothallon sanguineum'' assigned as the type species. Tobler erroneously believed that the fungus was a member of the Basidiomycota. After it was recognized as an ascolichen, it was referred to either ''Chiodecton'' (family Roccellaceae) or ''Cryptothecia'' (family Arthoniaceae). In 2009, ''Herpothallon'' was resurrected following a publication by André Aptroot, Göran Thor, Robert Lücking, and John Alan Elix, John Elix, in which they recognized 29 species worldwide. The type species is now known as ''Herpothallon rubrocinctum'', or in the common name, vernacular as the "Christmas lichen". Description ''Herpothallon'' is characterized by the byssoid lichen, byssoid (a wispy or cottony texture) prothallus (i.e., the first purely fungal layer upon which an a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cryptothecia
''Cryptothecia'' is a genus of white to greenish crustose lichens that grow on bark, wood, or leaves. in tropical or subtropical areas worldwide. It has a conspicuous prothallus that develops around its periphery which can be bright red in some species, hence the common name wreath lichen. The main vegetative body (thallus) lacks a cortex (ecorticate and is often immersed in the substrate or byssoid (whispy, like teased wool). The medulla is white, well defined, and often peppered with calcium oxalate crystals. Ascomata are not well defined, being cushions of soft white mycelium immersed in the medullary tissue, hence the name from the Greek ''krypto'' = "to conceal" and ''theke'' = "a container or sheath". There are about 45 described species in the genus according to one source, and 75 species according to another. The genus is in the family Arthoniaceae. It contains '' Trentepohlia'', a green alga, as its photobiont partner. Two species have been described in North America.B ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arthoniaceae
The Arthoniaceae are a family of lichenized, lichenicolous and saprobic fungi in the order Arthoniales. The Arthoniaceae is the largest family of Arthoniales, with around 800 species. Most species in Arthoniaceae belong in '' Arthonia'' which is the largest genus with 500 species. The second and third largest genus is '' Arthothelium'' with 80 species, and ''Cryptothecia'' with 60 species. ''Arthonia'' is the type genus of Arthoniaceae, and it is known to be a polyphyletic and paraphyletic genus. The process of splitting ''Arthonia'' into monophyletic groups is an ongoing process. In order to make ''Arthonia'' monophyletic, several genera have been described or resurrected. Distribution The species in Arthoniaceae have a worldwide distribution, but are especially prevalent in tropical areas with a Mediterranean climate. They are known from arctic to tropical latitudes, as well as variating altitudes from sea level to alpine regions, distributed in both humid forests and dry habit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Byssoid Lichen
Lichens are composite organisms made up of multiple species: a fungal partner, one or more photosynthetic partners, and sometimes a basidiomycete yeast. They are regularly grouped by their external appearance – a characteristic known as their growth form. Lichenologists have described a dozen of these forms: areolate, byssoid, calicioid, cladoniform, crustose, filamentous, foliose, fruticose, gelatinous, leprose, placoidioid and squamulose. Of these, crustose, foliose and fruticose are the most commonly encountered. With the exception of calicioid lichens, growth forms are based on the appearance of the thallus, which is the vegetative (non-reproductive) part of the lichen. In most species, this form is determined by the lichen's fungal partner, though in a small number, it is instead the photobiont that determines the lichen's morphology. In some growth forms, the outermost layer of the thallus consists of tightly woven fungal . This layer, known as the cortex, may be found o ... [...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] |
Green Alga
The green algae (singular: green alga) are a group consisting of the Prasinodermophyta and its unnamed sister which contains the Chlorophyta and Charophyta/Streptophyta. The land plants (Embryophytes) have emerged deep in the Charophyte alga as sister of the Zygnematophyceae. Since the realization that the Embryophytes emerged within the green algae, some authors are starting to properly include them. The completed clade that includes both green algae and embryophytes is monophyletic and is referred to as the clade Viridiplantae and as the kingdom Plantae. The green algae include unicellular and colonial flagellates, most with two flagella per cell, as well as various colonial, coccoid and filamentous forms, and macroscopic, multicellular seaweeds. There are about 22,000 species of green algae. Many species live most of their lives as single cells, while other species form coenobia (colonies), long filaments, or highly differentiated macroscopic seaweeds. A few other organ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trentepohlia (alga)
''Trentepohlia'' is a genus of filamentous chlorophyte green algae in the family Trentepohliaceae, living free on terrestrial supports such as tree trunks and wet rocks or symbiotically in lichens. The filaments of ''Trentepohlia'' have a strong orange colour (photograph at right) caused by the presence of large quantities of carotenoid pigments which mask the green of the chlorophyll. ''Trentepohlia'' species form associations with fungal hyphae, and are widespread phycobionts in lichens, such as the "secret writing" crustose lichen genera '' Graphis'', ''Graphina'', ''Gyalecta'' and ''Opegrapha''.F.S. Dobson (2000) Lichens, an illustrated guide to the British and Irish species. Richmond publishing Co. T. Friedl and B. Büdel (1996) Photobionts, in Nash, T.H. (ed.) Lichen biology, pp.8-23, Cambridge University Press. There are about 40 species of ''Trentepohlia'' mostly distributed in tropical and subtropical areas but several species also occur in temperate environments inclu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Soredia
Soredia are common reproductive structures of lichens. Lichens reproduce asexually by employing simple fragmentation and production of soredia and isidia. Soredia are powdery propagules composed of fungal hyphae wrapped around cyanobacteria or green algae. These can be either scattered diffusely across the surface of the lichen's 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 wer ..., or produced in localized structures called soralia. Fungal hyphae make up the basic body structure of lichen. The soredia are released through openings in the upper cortex of the lichen structure. After their release, the soredia disperse to establish the lichen in a new location. References Fungal morphology and anatomy Lichenology {{lichen-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Granule (cell Biology)
In cell biology, a granule is a small particle. It can be any structure barely visible by light microscopy. The term is most often used to describe a secretory vesicle. In leukocytes A group of leukocytes, called granulocytes, contain granules and play an important role in the immune system. The granules of certain cells, such as natural killer cells, contain components which can lead to the lysis of neighboring cells. The granules of leukocytes are classified as azurophilic granules or specific granules. Leukocyte granules are released in response to immunological stimuli during a process known as degranulation. In platelets The granules of platelets are classified as dense granules and alpha granules. α-Granules are unique to platelets and are the most abundant of the platelet granules, numbering 50–80 per platelet 2. These granules measure 200–500 nm in diameter and account for about 10% of platelet volume. They contain mainly proteins, both membrane-associated ... [...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] |
Isidia
An isidium is a vegetative reproductive structure present in some lichens. Isidia are outgrowths of the thallus surface, and are corticated (i.e., containing the outermost layer of the thallus), usually with a columnar structure, and consisting of both fungal hyphae (the mycobiont) and algal cells (the photobiont). They are fragile structures and may break off and be distributed by wind, animals, and splashing raindrops. In terms of structure, isidia may be described as warty, cylindrical, clavate (club-shaped), scale-like, coralloid (coral-shaped), simple, or branched. Examples of isidiate lichens include members of the genera ''Parmotrema'' and ''Peltigera''. See also Soredium Soredia are common reproductive structures of lichens. Lichens reproduce asexually by employing simple fragmentation and production of soredia and isidia. Soredia are powdery propagules composed of fungal hyphae wrapped around cyanobacteria o ... References External linksAscomycetes glossary ... [...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] |
