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Sphaeropleales
Sphaeropleales is an order of green algae that used to be called Chlorococcales. The order includes some of the most common freshwater plankton Plankton are the diverse collection of organisms that drift in Hydrosphere, water (or atmosphere, air) but are unable to actively propel themselves against ocean current, currents (or wind). The individual organisms constituting plankton are ca ...ic algae such as '' Scenedesmus'' and '' Pediastrum''. The Sphaeropleales includes vegetatively non-motile unicellular, colonial , or filamentous taxa. They have biflagellate zoospores with flagella that are directly opposed in direction (the DO arrangement): '' Sphaeroplea'', '' Atractomorpha'', '' Neochloris'', '' Hydrodictyon'', and '' Pediastrum''. All of these taxa have basal body core connections. Motile cells generally lack cell walls or have only a very fine layer surrounding the cell membrane. Other common characteristics include a robust vegetative cell wall, cup-shaped ch ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bracteamorphaceae
''Bracteamorpha'' is a genus of green algae in the order Sphaeropleales, and is the only genus in the family Bracteamorphaceae. It contains a single species, ''Bracteamorpha trainorii''. ''Bracteamorpha'' is a terrestrial alga that inhabits soils. It was first discovered in a biological soil crust from a desert in New Mexico, USA. Description ''Bracteamorpha trainorii'' consists of solitary cells that are roughly spherical to ovoid, up to 24 μm long. When young, the cells have a single parietal lobed chloroplast; at maturity, cells have many small chloroplasts, both lining the outer wall (i.e. parietal) and deeper within the cell. Chloroplasts lack sheathed pyrenoids. Mature cells are multinucleate; that is, they have multiple cell nucleus, nuclei. Old cells may be orange in color due to the presence of carotenoid pigments. ''Bracteamorpha'' reproduces asexual reproduction, asexually and sexually. Asexual reproduction occurs by the formation of autospores, or zoospores. In auto ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sphaeropleaceae
Sphaeropleaceae is a family of green algae in the order Sphaeropleales. The Sphaeropleaceae consists of solitary cells or filaments of cells. They are coenocytic, and reproduce asexually via zoospores or sexually via anisogamy or oogamy. The family has had a convoluted taxonomic history. Depending on the author, it has been placed in one of many orders including Ulotrichales or Chaetophorales. Currently, it is placed in its own order, the Sphaeropleales. It appears to be the sister group In phylogenetics, a sister group or sister taxon, also called an adelphotaxon, comprises the closest relative(s) of another given unit in an evolutionary tree. Definition The expression is most easily illustrated by a cladogram: Taxon A and ... to the rest of the families in its order. It also differs from the other families in the ultrastructure of the basal bodies of their flagella. References Chlorophyceae families Sphaeropleales {{Chlorophyceae-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mychonastaceae
''Mychonastes'' is a genus of green algae, specifically of the Chlorophyceae. It is the sole genus of the family Mychonastaceae. Species of ''Mychonastes'' are found in plankton of freshwater or brackish waters, or found in soil. It is a very common genus, and is often dominant. Description ''Mychonastes'' consists of solitary cells of groups of a few cells (rarely more than four). Cells are spherical or slightly ovate, uninucleate (with one nucleus) and a single parietal chloroplast without any pyrenoids. The cell wall is covered in an irregular network of ridges, only visible in (scanning electron microscopy). Cells are sometimes connected together by irregular, mucilaginous strands. These mucilaginous strands are formed from the mother cell wall after autospore release. ''Mychonastes'' reproduces asexually via autospores. Usually 2 or 4 (sometimes up to 64) are produced per cell. They are released through a tear in the cell wall. Species are differentiated from each other by ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Characiaceae
Characiaceae is a family of green algae in the order Sphaeropleales. It contains epiphytic or planktonic algae that are unicellular or colonial. The cells are heteropolar, with basal and apical ends having different shapes. The daughter cells are often retained in the cell wall of the old mother cell, whose cell wall becomes gelatinized. Taxonomy The taxonomy of Characiaceae has undergone significant revision in the last century. Characiaceae once included genera such as '' Schroederia'', but that circumscription made the family polyphyletic, so many of those genera have been transferred to other families. However, the taxonomic affiliation of the type species of the genus ''Characium'' (''C. sieboldii'') is still unclear, which necessitates further revision of the family. , 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, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pediastrum
''Pediastrum'' is a genus of green algae, in the family Hydrodictyaceae. It is a photoautotrophic, nonmotile coenobial green alga that inhabits freshwater environments. The name ''Pediastrum'' comes from the Greek root words ''pedion'', meaning "plane", and ''astron'', meaning "star", referring to its overall shape. Morphology ''Pediastrum'' develops colonies with a fixed number of cells, termed coenobia. In this case, the coenobia are composed of between 22 and 27 cells, which are orderly arranged in a flat disk. The diameter of a single coenobium ranges from 20 to 80 μm, making them microalgae. Cells in ''Pediastrum'' are dimorphic, consisting of interior cells and peripheral cells, distinguished by their position in the colony and by their shape. Some species have inter-cellular spaces between their interior cells. The peripheral cells surround the interior cells, and they usually possess bristles, V-like cutting edges, or wavy projections. ''Pediastrum'' shows lots of m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dictyochloridaceae
''Dictyochloris'' is a genus of green algae in the class Chlorophyceae. It is the sole genus of the family Dictyochloridaceae. It is commonly found in terrestrial and subaerial habitats. The genus ''Dictyochloris'' was first described by Wilhelm Vischer in 1945. Later, it was re-investigated by Richard C. Starr in 1955. It is not to be confused with ''Dictyochloris'' , which is an later (and thus illegitimate) homonym because it was described after Vischer used the name ''Dictyochloris''. Because it is illegitimate, that genus was renamed to '' Dictyochlorella''. Etymology The scientific name ''Dictyochloris'' has roots in the Greek language. The prefix “dictyo” is derived from the Greek word “δίκτυο” or “díktyo” meaning “network”, which is in reference to the net-like chloroplast present in this genus. The medial “-chloro-” is from “χλωρός” or “chloros” meaning “the colour green” because of the green pigment, chlorophyll, which col ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polyedriopsis
''Polyedriopsis'' is a genus of green algae in the order Sphaeropleales. , it contained a single species, ''Polyedriopsis spinulosa''. It is found worldwide in freshwater habitats as phytoplankton, but is rare. ''Polyedriopsis spinulosa'' consists of solitary or sometimes clustered cells, 12–25 μm in diameter. They are four- or five-sided with concave sides; the corners are rounded off and bear a tuft of 3-10 thin tapering spines, 25–50 μm long. Cells are uninuclate (with one nucleus and contain a single parietal chloroplast with one pyrenoid. ''Polyedriopsis spinulosa'' reproduces asexually via the formation of zoospores, of which 4 to 8 are produced per cell. Zoospores are ovate, with two flagella A flagellum (; : flagella) (Latin for 'whip' or 'scourge') is a hair-like appendage that protrudes from certain plant and animal sperm cells, from fungal spores ( zoospores), and from a wide range of microorganisms to provide motility. Many pr ... and a stigma. Referenc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrodictyaceae
Hydrodictyaceae is a family of green algae in the order Sphaeropleales. They are found in freshwater habitats worldwide. Members of this family are either unicellular or colonial. Cells are cylindrical, polyhedral, spherical, or sometimes nearly spherical. Cells contain a single parietal, chloroplast with a pyrenoid. The cell wall may be smooth or covered in warts, ribs or other ornamentation. Reproduction can occur asexually or sexually. In asexual reproduction, the mother cell becomes a number of zoospores and swim inside the enlarged mother cell wall, until they attach to each other and become a new colony. In '' Tetraedron'', the cells do not produce zoospores but produce autospores within the enlarged mother cell wall. Sexual reproduction, when observed, occurs via isogamous gametes. Because the cell wall of some Hydrodictyaceae contain sporopollenin, they decay very slowly and thus last long in the fossil record. Genera The family Hydrodictyaceae includes the following ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neochloridaceae
Neochloridaceae is a family of green algae in the order Sphaeropleales. Neochloridaceae consists of aquatic, coccoid algae. The cells are spherical or with complex polyhedral shapes. Chloroplasts have pyrenoids that are surrounded by continuous starch sheaths. They reproduce via asexual reproduction, where the cell forms aplanospores or zoospores; the zoospores bear two flagella. Phylogenetically, Neochloridaceae is sister to the family Hydrodictyaceae, a family which contains common and well-known algae such as ''Pediastrum ''Pediastrum'' is a genus of green algae, in the family Hydrodictyaceae. It is a photoautotrophic, nonmotile coenobial green alga that inhabits freshwater environments. The name ''Pediastrum'' comes from the Greek root words ''pedion'', meaning ...''. References Chlorophyceae families Sphaeropleales {{Chlorophyceae-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nephrocytiaceae
''Nephrocytium'' is a genus of green algae in the class Chlorophyceae. Formerly placed in the family Oocystaceae, it is currently placed in its own family, Nephrocytiaceae. The name ''Nephrocytium'' is derived from the Ancient Greek νεφρός (''nephrós'', "kidney") and κύτος (''kytos'', "vessel"). Description ''Nephrocytium'' consists of colonies of 4, 8, or 16 asymmetrical cells surrounded by a spherical to ovoid layer of mucilage, which is formed when the mother cell wall expands and gelatinizes. Individual cells are kidney-shaped to ovoid, containing one chloroplast lining the inside of the cell membrane, each with one pyrenoid. Reproduction occurs asexually. It exclusively forms autospore Autospores are a type of spores that are produced by algae to enable asexual reproduction and spread. They are non-motile and non-Flagellated cell, flagellated Aplanospore, aplanospores that are generated within a parent cell and have the same sha ...s, and does not appear to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pseudomuriellaceae
''Pseudomuriella'' is a genus of green algae in the class Chlorophyceae. It is the sole genus of the family Pseudomuriellaceae. It is a terrestrial alga that inhabits soils. Description ''Pseudomuriella'' consists of solitary, spheroidal cells surrounded by a smooth cell wall. Young cells have a single nucleus, but mature cells have nuclei (i.e. are multinucleate). Each cell has multiple chloroplasts lining the outside of the cell; each chloroplast is saucer-shaped when young and divided into multiple segments when older. Chloroplasts lack pyrenoids. Cells may have secondary carotenoids present, giving the cells an orange color especially when old. ''Pseudomuriella'' reproduces asexually, mainly by autospores, but sometimes by aplanospores or biflagellated zoospore A zoospore is a motile asexual spore that uses a flagellum for locomotion in aqueous or moist environments. Also called a swarm spore, these spores are created by some protists, bacteria, and fungi to propagate th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Selenastraceae
Selenastraceae is a family of green algae in the order Sphaeropleales. Members of this family are common components of the phytoplankton in freshwater habitats worldwide. A few species have been found in brackish and marine habitats, such as in the Baltic Sea. Description The family Selenastraceae includes solitary cells or colonies of cells. Cells are diverse in morphology; they may be coccoid to spindle-shaped in shape, with rounded or pointed ends. They may be sickle-shaped or spirally curved. Cells contain a chloroplast with a pyrenoid. Except in the genus '' Chlorolobion'', the pyrenoid lacks a starch covering, making it difficult to observe using light microscopy. Cells range in size from 5 to 105 μm in length and 1.5 to 6.5 μm in width. Algae in this family reproduce asexually, exclusively by autospores. A distinguishing characteristic of this family is the method of autospore formation: the protoplast divides serially, with divisions being perpendicular to the longer a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |