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Streptophyta
Streptophyta (), informally the streptophytes (, from the Greek ''strepto'' 'twisted', for the morphology of the sperm of some members), is a clade of plants. The composition of the clade varies considerably between authors, but the definition employed here includes land plants and all green algae except the Chlorophyta and the more basal Prasinodermophyta. Classifications The composition of Streptophyta and similar groups (Streptophytina, Charophyta) varies in each classification. Some authors include only the Charales and Embryophyta (e.g., Streptophyta, Streptophytina); others include more groups (e.g., Charophyta, Streptophyta, Streptobionta); some authors use this broader definition, but exclude the Embryophyta (e.g., Charophyta, Charophyceae, Streptophycophytes). The clade Streptophyta includes both unicellular and multicellular organisms. Streptophyta contains the freshwater charophyte green algae and all land plants that reproduce sexually by conjugation. ''Mesostigma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Charophyta
Charophyta () is a paraphyletic group of freshwater green algae, called charophytes (), sometimes treated as a division, yet also as a superdivision. The terrestrial plants, the Embryophyta emerged deep within Charophyta, possibly from terrestrial unicellular charophytes, with the class Zygnematophyceae as a sister group. With the Embryophyta now cladistically placed in the Charophyta, it is a synonym of Streptophyta. The sister group of the charophytes are the Chlorophyta. In some charophyte groups, such as the Zygnematophyceae or conjugating green algae, flagella are absent and sexual reproduction does not involve free-swimming flagellate sperm. Flagellate sperm, however, are found in stoneworts ( Charales) and Coleochaetales, orders of parenchymatous charophytes that are the closest relatives of the land plants, where flagellate sperm are also present in all except the conifers and flowering plants. Fossil stoneworts of early Devonian age that are similar to those of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mesostigma
''Mesostigma'' is a genus of unicellular biflagellate freshwater green algae, with a single species ''Mesostigma viride'', covered by an outer layer of basket‐like scales instead of a cell wall. It is the only known genus in the class Mesostigmatophyceae (and thus, the only genus in the family Mesostigmataceae and the order Mesostigmatales). Earlier studies were unable to resolve the position of the species, and it was often placed as a sister to all other green algae, as one of the basal members of the Streptophyta, close to '' Chaetosphaeridium''. More recent studies agree that ''Mesostigma'' and '' Chlorokybus'' form a clade, being the earliest diverging of the green plants, specifically within Charophytes Charophyta () is a Paraphyly, paraphyletic group of freshwater green algae, called charophytes (), sometimes treated as a Division (taxonomy), division, yet also as a Division (taxonomy), superdivision. The terrestrial plants, the Embryophyta em .... References ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Streptophytina
The Phragmoplastophyta (Lecointre & Guyader 2006) are a proposed sister clade of the Klebsormidiaceae in the Streptophyte/ Charophyte clade. The Phragmoplastophyta consist of the Charophyceae and another unnamed clade which contains the Coleochaetophyceae, Zygnematophyceae, Mesotaeniaceae, and Embryophytes (land plants). It is an important step in the emergence of land plants within the green algae. It is equivalent to the ZCC clade/grade, cladistically granting the Embryophyta. The mitosis of Phragmoplastophyta takes place via a phragmoplast. Another synapomorphy In phylogenetics, an apomorphy (or derived trait) is a novel Phenotypic trait, character or character state that has evolution, evolved from its ancestral form (or Plesiomorphy and symplesiomorphy, plesiomorphy). A synapomorphy is an apomorphy sh ... of this clade is the synthesis of cellulose microfibrils by a complex of octameric cellulose synthetases. This complex crosses the plasma membrane and polymerize ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phragmoplastophyta
The Phragmoplastophyta (Lecointre & Guyader 2006) are a proposed sister clade of the Klebsormidiaceae in the Streptophyte/Charophyte clade. The Phragmoplastophyta consist of the Charophyceae and another unnamed clade which contains the Coleochaetophyceae, Zygnematophyceae, Mesotaeniaceae, and Embryophytes (land plants). It is an important step in the emergence of land plants within the green algae. It is equivalent to the ZCC clade/grade, cladistically granting the Embryophyta. The mitosis of Phragmoplastophyta takes place via a phragmoplast. Another synapomorphy In phylogenetics, an apomorphy (or derived trait) is a novel Phenotypic trait, character or character state that has evolution, evolved from its ancestral form (or Plesiomorphy and symplesiomorphy, plesiomorphy). A synapomorphy is an apomorphy sh ... of this clade is the synthesis of cellulose microfibrils by a complex of octameric cellulose synthetases. This complex crosses the plasma membrane and polymerizes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Prasinodermophyta
The marine Prasinodermophyta are a proposed basal Viridiplantae clade, as sister of another clade comprising the Chlorophyta and the Streptophyta Streptophyta (), informally the streptophytes (, from the Greek ''strepto'' 'twisted', for the morphology of the sperm of some members), is a clade of plants. The composition of the clade varies considerably between authors, but the definition e .... It consists of the Prasinodermophyceae and the Palmophyllophyceae, and is informally called prasinodermophytes. They were previously considered to be a basal Chlorophyta clade, or part of the " prasinophytes". References Green algae phyla {{green alga-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Viridiplantae
Viridiplantae (; kingdom Plantae '' sensu stricto'') is a clade of around 450,000–500,000 species of eukaryotic organisms, most of which obtain their energy by photosynthesis. The green plants are chloroplast-bearing autotrophs that play important primary production roles in both terrestrial and aquatic ecosystems. They include green algae, which are primarily aquatic, and the land plants (embryophytes, Plantae '' sensu strictissimo''), which emerged within freshwater green algae. Green algae traditionally excludes the land plants, rendering them a paraphyletic group, however it is cladistically accurate to think of land plants as a special clade of green algae that evolved to thrive on dry land. Since the realization that the embryophytes emerged from within the green algae, some authors are starting to include them. Viridiplantae species all have cells with cellulose in their cell walls, and primary chloroplasts derived from endosymbiosis with cyanobacteria that contain c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zygnemophyceae
Zygnematophyceae (or Conjugatophyceae) is a class of green algae in the paraphylum streptophyte algae, also referred to as Charophyta, consisting of more than 4000 described species. The Zygnematophyceae are the sister clade of the Embryophyta (land plants). Common members of the Zygnematophyceae include the filamentous algae ''Spirogyra'' and ''Mougeotia'', as well as desmids, which are microscopic algae characterized by symmetrical and elaborately ornate cells. Morphology The body plan of Zygnematophyceae is simple, and the group appears to have gone through a secondary loss of morphological complexity. The most basal members are unicellular, but filamentous species have evolved at least five times, and a few species form colonies. Each cell contains a single cell nucleus, nucleus. The chloroplasts of the Zygnematophyceae are large, typically axile but sometimes parietally located, and contain one or several pyrenoids. One or several chloroplasts may be present in a single cel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mesostigmatophyceae
The Mesostigmatophyceae are a class of basal green algae found in freshwater. In a narrow circumscription, the class contains a single genus, '' Mesostigma''. AlgaeBase AlgaeBase is a global species database of information on all groups of algae, both seaweed, marine and freshwater algae, freshwater, as well as sea-grass. History AlgaeBase began in March 1996, founded by Michael D. Guiry, Michael Guiry. Text ... then places the class within its circumscription of Charophyta. A clade containing '' Chlorokybus'' and '' Spirotaenia'' may either be added, or treated as a sister, with ''Chlorokybus'' placed in a separate class, Chlorokybophyceae. When broadly circumscribed, Mesostigmatophyceae may be placed as sister to all other green algae, or as sister to all Streptophyta. References External links * AlgaTerra databaseIndex Nominum Genericorum Green algae classes Charophyta {{green algae-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zygnematophyceae
Zygnematophyceae (or Conjugatophyceae) is a class of green algae in the paraphylum streptophyte algae, also referred to as Charophyta, consisting of more than 4000 described species. The Zygnematophyceae are the sister clade of the Embryophyta (land plants). Common members of the Zygnematophyceae include the filamentous algae ''Spirogyra'' and '' Mougeotia'', as well as desmids, which are microscopic algae characterized by symmetrical and elaborately ornate cells. Morphology The body plan of Zygnematophyceae is simple, and the group appears to have gone through a secondary loss of morphological complexity. The most basal members are unicellular, but filamentous species have evolved at least five times, and a few species form colonies. Each cell contains a single nucleus. The chloroplasts of the Zygnematophyceae are large, typically axile but sometimes parietally located, and contain one or several pyrenoids. One or several chloroplasts may be present in a single cell. The shape ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
