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Cercozoa
Cercozoa is a phylum of diverse single-celled eukaryotes. They lack shared morphological characteristics at the microscopic level, and are instead defined by molecular phylogenies of rRNA and actin or polyubiquitin. They were the first major eukaryotic group to be recognized mainly through molecular phylogenies. They are the natural predators of many species of microbacteria and Archea. They are closely related to the phylum Retaria, comprising amoeboids that usually have complex shells, and together form a supergroup called Rhizaria. Characteristics The group includes most amoeboids and flagellates that feed by means of filose pseudopods. These may be restricted to part of the cell surface, but there is never a true cytostome or mouth as found in many other protozoa. They show a variety of forms and have proven difficult to define in terms of structural characteristics, although their unity is strongly supported by phylogenetic studies. Diversity Some cercozoans are grouped ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Filosa
Cercozoa is a phylum of diverse single-celled eukaryotes. They lack shared morphological characteristics at the microscopic level, and are instead defined by molecular phylogenies of rRNA and actin or polyubiquitin. They were the first major eukaryotic group to be recognized mainly through molecular phylogenies. They are the natural predators of many species of microbacteria and Archea. They are closely related to the phylum Retaria, comprising amoeboids that usually have complex shells, and together form a supergroup called Rhizaria. Characteristics The group includes most amoeboids and flagellates that feed by means of filose pseudopods. These may be restricted to part of the cell surface, but there is never a true cytostome or mouth as found in many other protozoa. They show a variety of forms and have proven difficult to define in terms of structural characteristics, although their unity is strongly supported by phylogenetic studies. Diversity Some cercozoans are grouped by ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rhizaria
The Rhizaria are an ill-defined but species-rich supergroup of mostly unicellular eukaryotes. Except for the Chlorarachniophytes and three species in the genus Paulinella in the phylum Cercozoa, they are all non-photosynthethic, but many foraminifera and radiolaria have a symbiotic relationship with unicellular algae. A multicellular form, ''Guttulinopsis vulgaris'', a cellular slime mold, has also been described. This group was used by Cavalier-Smith in 2002, although the term "Rhizaria" had been long used for clades within the currently recognized taxon. Being described mainly from rDNA sequences, they vary considerably in form, having no clear morphological distinctive characters (synapomorphies), but for the most part they are amoeboids with filose, reticulose, or microtubule-supported pseudopods. In the absence of an apomorphy, the group is ill-defined, and its composition has been very fluid. Some Rhizaria possess mineral exoskeleton (thecae or loricas), which is in differ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cercomonas
Cercomonads are small flagellates, widespread in aqueous habitats and common in soils. Characteristics The cells are generally around 10 μm in length, without any shell or covering. They produce filose pseudopods to capture bacteria, but do not use them for locomotion, which usually takes place by gliding along surfaces. Most members have two flagella, one directed forward and one trailing under the cell, inserted at right angles near its anterior. The nucleus is connected to the flagellar bases and accompanied by a characteristic paranuclear body. Classification Genetic studies place the cercomonads among the Cercozoa, a diverse group of amoeboid and flagellate protozoans. They are divided into two families. * The Heteromitidae tend to be relatively rigid, and produce only temporary pseudopods. * The Cercomonadidae are more plastic, and when food supplies are plentiful may become amoeboid and even multinucleate. The classification of genera and species continues to u ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Endomyxa
Endomyxa is a subphylum of Rhizaria The Rhizaria are an ill-defined but species-rich supergroup of mostly unicellular eukaryotes. Except for the Chlorarachniophytes and three species in the genus Paulinella in the phylum Cercozoa, they are all non-photosynthethic, but many foramini .... References External links Bikont subphyla {{Cercozoa-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Monadofilosa
Monadofilosa is a grouping of Cercozoa. (It is sometimes considered one of three, the other two being Phytomyxa and Reticulofilosa.) These organisms are single-celled amoeboid protists. Classification Monadofilosa includes the testaceans, which are testate filose amoeboids, and the cercomonads. It is sometimes described as Testaceafilosia and Sarcomonadea. It has also been described as Sarcomonadea ('' Cercomonas, Heteromita, Bodomorpha, Proleptomonas, Allantion''), Thecofilosea (''Cryptodifflugia, Cryothecomonas''), Spongomonadea ('' Spongomonas, Rhipidodendron''), and Imbricatea ('' Thaumatomonas, Thaumatomastix, Allas, Gyromitus, Euglypha, Trinema, Paulinella''). * The testaceans live both in marine and freshwater habitats, and in mosses. Members include '' Lecythium'', '' Pseudodifflugia'', ''Euglypha'' (a euglyphid), and ''Paulinella chromatophora''. * Cercomonads are flagellates that glide on their posterior cilium and/or generate filopodia. Members of t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ventrifilosa
Ventrifilosa () is a highly diverse group of phagotrophic protists that glide through their flagella and emit filose pseudopods from their ventral side for feeding. Because of their mixture of amoeba and flagellate characteristics, they are amoeboflagellates. Members of this group are the Imbricatea, Sarcomonadea and Thecofilosea. Morphology Protists in the group Ventrifilosa ancestrally have a rigid extracellular theca on the dorsal side, and emit non-granular filose pseudopods from a ventral aperture. This aperture is called "cleft" when belonging to an amoeboflagellate, or "astropyle" when belonging to a phaeodarian. The group includes descendants that have lost or modified some of these characteristics. For example, some have lost their pseudopods (such as the spongomonads and '' Ebria''), some have lost their theca (such as '' Pseudopirsonia''), and some have acquired axopodia (in Phaeodaria). The loss of flagella and scales has occurred in this group several times indepen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phytomyxea
The Phytomyxea are a class of parasites that are cosmopolitan, obligate biotrophic protist parasites of plants, diatoms, oomycetes and brown algae. They are divided into the orders Plasmodiophorida (ICZN, or Plasmodiophoromycota, ICBN) and Phagomyxida. Plasmodiophorids are best known as pathogens or vectors for viruses of arable crops (e.g. club root in Brassicaceae, powdery scab in potatoes, and rhizomania in beets, especially sugar beets and some spinaches). Life cycle They typically develop within plant cells, causing the infected tissue to grow into a gall or scab. Important diseases caused by phytomyxeans include club root in cabbage and its relatives, and powdery scab in potatoes. These are caused by species of ''Plasmodiophora'' and ''Spongospora'', respectively.Agrios, George N. (2005). ''Plant Pathology''. 5th ed. Academic Presslink The vegetative form is a multinucleate cell, called a plasmodium. This ultimately divides to form new spores, which are released w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ascetosporea
The Ascetosporea are a group of eukaryotes that are parasites of animals, especially marine invertebrates. The two groups, the haplosporids and paramyxids, are not particularly similar morphologically, but consistently group together on molecular trees, which place them near the base of the Cercozoa. Both produce spores without the complex structures found in similar groups (such as polar filaments or tubules). Haplosporid spores have a single cell nucleus, nucleus and an opening at one end, covered with an internal diaphragm or a distinctive hinged lid. After emerging, it develops within the cells of its host, usually a marine Mollusca, mollusc or annelid, although some infect other groups or freshwater species. The trophic cell is generally multinucleated. Paramyxids develop within the digestive system of marine invertebrates, and undergo internal budding to produce multicellular spores. A 2009 study concluded that ''Haplosporidium'' species form a paraphyletic group and that ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vampyrellidea
Aconchulinida is an order of Cercozoa in the subclass Filosia. The outer zone is clear ectoplasm and has many vacuoles. It has a single nucleus. Its size range from 10 to 400 micrometers. It contains few genera, possibly including only ''Penardia'', but usually also considered to encompass all of the Vampyrellidae The family Vampyrellidae is a subgroup of the order Aconchulinida (formerly Vampyrellida) within the phylum Cercozoa. Based on molecular sequence data, the family currently comprises the genus ''Vampyrella'', and maybe several other vampyrellid .... References {{Cercozoa-stub Cercozoa orders ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Granofilosea
Granofilosea is a class of cercozoans in the subphylum Filosa. Three groups that were traditionally considered heliozoans belong here: the Heliomonadida, Desmothoracida and Gymnosphaerida, which were recently grouped into the new class of Granofilosea. Taxonomy * Class Granofilosea Cavalier-Smith & Bass 2009 ** Family ? Microgromiidae De Saedeleer 1934 *** Genus '' Apogromia'' de Saedeleer 1934 *** Genus '' Belaria'' de Saedeleer 1934 *** Genus '' Heterogromia'' de Saedeleer 1934 *** Genus '' Microgromia'' Hertwig & Lesser 1874 *** Genus '' Paralieberkuehnia'' de Saedeleer 1934 ** Order ? Axomonadida xonucleoaxoplastiales*** Family Tetradimorphidae Febvre-Chevalier & Febvre 1984 **** Genus '' Tetradimorpha'' Hsiung 1927 ** Order Desmothoracida Honigberg et al. 1964 ryptaxohelida; Desmothoraca Hertwig & Lesser 1874; Clathrulinida Starobogatov 1980*** Family Clathrulinidae Claus 1874 **** Genus '' Actinosphaeridium'' Zacharias 1893 **** Genus '' Cienkowskya'' Schaudinn 1896 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amoeboid
An amoeba (; less commonly spelled ameba or amœba; plural ''am(o)ebas'' or ''am(o)ebae'' ), often called an amoeboid, is a type of cell or unicellular organism with the ability to alter its shape, primarily by extending and retracting pseudopods. Amoebae do not form a single taxonomic group; instead, they are found in every major lineage of eukaryotic organisms. Amoeboid cells occur not only among the protozoa, but also in fungi, algae, and animals. Microbiologists often use the terms "amoeboid" and "amoeba" interchangeably for any organism that exhibits amoeboid movement. In older classification systems, most amoebae were placed in the class or subphylum Sarcodina, a grouping of single-celled organisms that possess pseudopods or move by protoplasmic flow. However, molecular phylogenetic studies have shown that Sarcodina is not a monophyletic group whose members share common descent. Consequently, amoeboid organisms are no longer classified together in one group.Jan Pawlow ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rhizopoda
An amoeba (; less commonly spelled ameba or amœba; plural ''am(o)ebas'' or ''am(o)ebae'' ), often called an amoeboid, is a type of Cell (biology), cell or unicellular organism with the ability to alter its shape, primarily by extending and retracting pseudopodia, pseudopods. Amoebae do not form a single Taxonomy (biology), taxonomic group; instead, they are found in every major Lineage (evolution), lineage of eukaryote, eukaryotic organisms. Amoeboid cells occur not only among the protozoa, but also in fungi, algae, and animals. Microbiologists often use the terms "amoeboid" and "amoeba" interchangeably for any organism that exhibits amoeboid movement. In older classification systems, most amoebae were placed in the Class (biology), class or subphylum Sarcodina, a grouping of Unicellular organism, single-celled organisms that possess pseudopods or move by protoplasmic flow. However, molecular phylogenetic studies have shown that Sarcodina is not a monophyletic group whose memb ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
