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Glissomonadida
The glissomonads are a group of bacterivorous gliding flagellated protists that compose the order Glissomonadida, in the amoeboflagellate phylum Cercozoa. They comprise a vast, largely undescribed diversity of soil and freshwater organisms. They are the sister group to cercomonads; the two orders form a solid clade of gliding soil-dwelling flagellates called Pediglissa. Morphology External appearance Glissomonads are zooflagellates that aren't strongly amoeboid, and are only covered by a plasma membrane. Their common ancestor is thought to be a biflagellate, with a short anterior flagellum and a long posterior flagellum, that glided on the substrate by moving their posterior flagellum. In gliding descendants, the cell's posterior zone is usually rounded, giving the cell an ovoid shape. Some species may temporarily extend a protoplasmic tail, that unlike most cercomonads doesn't trail along the posterior flagellum. At least two genera, '' Orciraptor'' and '' Viridiraptor'' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pediglissa
Pediglissa () is a subclass of phagotrophic protists that inhabit soil or freshwater habitats. They were defined in 2018 according to phylogenetic analyses that showed a clade containing the orders Cercomonadida and Glissomonadida. They're the sister group of Paracercomonadida. Morphology and behavior Pediglissa are biciliate protists that glide on their posterior cilium and have a strong tendency to become amoeboid during feeding, unlike the metromonads. Their pseudopodia are more often shaped like rounded lamellae than finger-like or filose pseudopodia, unlike the paracercomonads. Their anterior cilium is often well developed, unlike in helkesids, but can be short in glissomonads; it moves with an undulating oar-like beat. The trophic cells (i.e. feeding forms) are naked, without a theca, scales, or perles, unlike in Thecofilosea and many freshwater Imbricatea. Diversity Pediglissa includes the majority of known cercozoan soil flagellates, all gliding on a single posterior c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Proleptomonas
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 this g ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Proleptomonadidae
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 this group contain ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cercomonad
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 un ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Viridiraptor
''Viridiraptor'' is a genus of heterotrophic protists, containing the single species ''Viridiraptor invadens''. It belongs to the family Viridiraptoridae, in the phylum Cercozoa. Morphology ''Viridiraptor'' are unicellular biflagellated organisms that have two blunt-ended, slightly unequal flagella and a peripheral conical nucleus closer to the cell's apical end, closely surrounded by several Golgi dictyosomes in its most anterior (anatomy) half. There are cortical extrusomes distributed homogenously across the cell periphery. Ecology and behavior Starving ''Viridiraptor'' cells can glide agitatedly while whipping their anterior flagellum, but they also commonly swim across the water column along a helical path. They invade dead or live cells of large-celled freshwater green algae to feed on their protoplast material, and also propagate within the lumen of the devoured cell. They can also extract plastids from small-celled algae. Etymology The name ''Viridiraptor'' (), meaning 'r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Viridiraptoridae
Viridiraptoridae, previously known as clade X, is a clade of heterotrophic protists in the phylum Cercozoa. They're a family of glissomonads, a group containing a vast, mostly undescribed diversity of soil and freshwater organisms. Morphology and behavior Members of Viridiraptoridae are unicellular biflagellates with naked cells, mostly rigid and variously shaped, without any rostrum or bulge. During the life cycle they can present two different states: a large flagellate state for moving, capable of changing into a surface-attached amoeboid state for feeding. The flagellate state exceeds 10 μm, unlike most known glissomonad families. The amoeboid state retains flagella and shows a bridge-like morphology, with several different adhesion sites. Each cell contains a single vesicular nucleus close to flagellar apparatus, and has an apical position in the flagellate state. The nucleolus is spherical, roughly central, occasionally showing lacunae. The Golgi dictyosomes are close to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aurigamonadidae
''Aurigamonas'' is a genus of predatory protists of an unusual cell structure, with two flagella and numerous haptopodia. It is a monotypic genus containing the single species ''Aurigamonas solis''. It is the only genus of the family Aurigamonadidae. Etymology The genus name comes from the Latin ''Auriga'', meaning charioteer, as a reference to the rein-like motion of the posterior flagellum. The species epithet comes from the Latin ''solis'', meaning sun, due to the Greek legend of the sun being drawn across the heavens by a charioteer. Morphology and movement ''Aurigamonas'' are unicellular zooflagellates with a spherical to ovoid shape (3–18 μm in diameter). Their most striking characteristic are the numerous long stiff haptopodia (around 30 to 50, each around 6 μm in length) radiating from the cell body, supported by microfilaments and tipped by a dense haptosome. They bear two cilia: the posterior, long and used for propulsion (9–52 μm), that beats in sinuous wav ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flagellate
A flagellate is a cell or organism with one or more whip-like appendages called flagella. The word ''flagellate'' also describes a particular construction (or level of organization) characteristic of many prokaryotes and eukaryotes and their means of motion. The term presently does not imply any specific relationship or classification of the organisms that possess flagella. However, the term "flagellate" is included in other terms (such as "dinoflagellate" and "choanoflagellata") which are more formally characterized. Form and behavior Flagella in eukaryotes are supported by microtubules in a characteristic arrangement, with nine fused pairs surrounding two central singlets. These arise from a basal body. In some flagellates, flagella direct food into a cytostome or mouth, where food is ingested. Flagella often support hairs, called mastigonemes, or contain rods. Their ultrastructure plays an important role in classifying eukaryotes. Among protoctists and microscopic anima ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Orciraptor Agilis
''Orciraptor'' is a genus of heterotrophic protists, containing the single species ''Orciraptor agilis''. It belongs to the family Viridiraptoridae, in the phylum Cercozoa. Morphology ''Orciraptor'' are unicellular organisms with two flagella: a short anterior and a long posterior. The cell nucleus is spherical, surrounded by several Golgi dictyosomes. They have cortical extrusomes homogenously distributed in the cell's periphery. In particular, ''Orciraptor agilis'' are colourless gliding cells that in ventral view are compact in shape, measuring 8–14 μm in length, and in lateral view are oviform or tear-shaped, measuring 12–20 μm in length. The posterior flagellum measures an average of 44 μm, while the anterior measures an average of 15 μm and is usually 33–35 % the length of the posterior flagellum. Their spherical nucleus averages 5 μm in diameter, while the nucleolus averages 3 μm, the mitochondria measure 1.5 × 0.7 μm, and the Golgi bodies appear 1.5–3 in l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Orciraptor
''Orciraptor'' is a genus of heterotrophic protists, containing the single species ''Orciraptor agilis''. It belongs to the family Viridiraptoridae, in the phylum Cercozoa. Morphology ''Orciraptor'' are unicellular organisms with two flagella: a short anterior and a long posterior. The cell nucleus is spherical, surrounded by several Golgi dictyosomes. They have cortical extrusomes homogenously distributed in the cell's periphery. In particular, ''Orciraptor agilis'' are colourless gliding cells that in ventral view are compact in shape, measuring 8–14 μm in length, and in lateral view are oviform or tear-shaped, measuring 12–20 μm in length. The posterior flagellum measures an average of 44 μm, while the anterior measures an average of 15 μm and is usually 33–35 % the length of the posterior flagellum. Their spherical nucleus averages 5 μm in diameter, while the nucleolus averages 3 μm, the mitochondria measure 1.5 × 0.7 μm, and the Golgi bodies appear 1.5–3 in l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anterior (anatomy)
Standard anatomical terms of location are used to unambiguously describe the anatomy of animals, including humans. The terms, typically derived from Latin or Greek roots, describe something in its standard anatomical position. This position provides a definition of what is at the front ("anterior"), behind ("posterior") and so on. As part of defining and describing terms, the body is described through the use of anatomical planes and anatomical axes. The meaning of terms that are used can change depending on whether an organism is bipedal or quadrupedal. Additionally, for some animals such as invertebrates, some terms may not have any meaning at all; for example, an animal that is radially symmetrical will have no anterior surface, but can still have a description that a part is close to the middle ("proximal") or further from the middle ("distal"). International organisations have determined vocabularies that are often used as standard vocabularies for subdisciplines of anatom ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plasma Membrane
The cell membrane (also known as the plasma membrane (PM) or cytoplasmic membrane, and historically referred to as the plasmalemma) is a biological membrane that separates and protects the interior of all cells from the outside environment (the extracellular space). The cell membrane consists of a lipid bilayer, made up of two layers of phospholipids with cholesterols (a lipid component) interspersed between them, maintaining appropriate membrane fluidity at various temperatures. The membrane also contains membrane proteins, including integral proteins that span the membrane and serve as membrane transporters, and peripheral proteins that loosely attach to the outer (peripheral) side of the cell membrane, acting as enzymes to facilitate interaction with the cell's environment. Glycolipids embedded in the outer lipid layer serve a similar purpose. The cell membrane controls the movement of substances in and out of cells and organelles, being selectively permeable to ions an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
