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Tectofilosid
The tectofilosids are a group of filose amoebae with shells. These are composed of organic materials and sometimes collected debris, in contrast to the euglyphids, which produce shells from siliceous scales. The shell usually has a single opening, but in '' Amphitrema'' and a few other genera it has two on opposite ends. The cell itself occupies most of the shell. They are most often found on marsh plants such as ''Sphagnum''. This group was previously classified as the Gromiida or Gromiina. However, molecular studies separate ''Gromia'' from the others, which must therefore be renamed. They are placed among the Cercozoa, and presumably developed from flagellates like ''Cryothecomonas'', which has a similar test. However, only a few have been studied in detail, so their relationships and monophyly are not yet certain. In a recent classification, the group Tectofilosida was not used: Chlamydophryidae, Psammonobiotidae, Pseudodifflugiidae and Volutellidae were dispersally plac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tectofilosida
The tectofilosids are a group of filose amoebae with shells. These are composed of organic materials and sometimes collected debris, in contrast to the euglyphids, which produce shells from siliceous scales. The shell usually has a single opening, but in '' Amphitrema'' and a few other genera it has two on opposite ends. The cell itself occupies most of the shell. They are most often found on marsh plants such as ''Sphagnum''. This group was previously classified as the Gromiida or Gromiina. However, molecular studies separate ''Gromia'' from the others, which must therefore be renamed. They are placed among the Cercozoa, and presumably developed from flagellates like ''Cryothecomonas'', which has a similar test. However, only a few have been studied in detail, so their relationships and monophyly are not yet certain. In a recent classification, the group Tectofilosida was not used: Chlamydophryidae, Psammonobiotidae, Pseudodifflugiidae and Volutellidae were dispersally plac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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] |
Euglyphid
The euglyphids are a prominent group of filose amoebae that produce shells or tests from siliceous scales, plates, and sometimes spines. These elements are created within the cell and then assembled on its surface in a more or less regular arrangement, giving the test a textured appearance. There is a single opening for the long slender pseudopods, which capture food and pull the cell across the substrate. Euglyphids are common in soils, marshes, and other organic-rich environments, feeding on tiny organisms such as bacteria. The test is generally 30-100 μm in length, although the cell only occupies part of this space. During reproduction a second shell is formed opposite the opening, so both daughter cells remain protected. Different genera and species are distinguished primarily by the form of the test. ''Euglypha'' and ''Trinema'' are the most common. The euglyphids are traditionally grouped with other amoebae. However, genetic studies instead place them with var ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
