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Ichthyosporea
The Mesomycetozoea (or DRIP clade, or Ichthyosporea) are a small group of Opisthokonta in Eukaryota (formerly protists), mostly parasites of fish and other animals. Significance They are not particularly distinctive morphologically, appearing in host tissues as enlarged spheres or ovals containing spores, and most were originally classified in various groups as fungi, protozoa, or colorless algae. However, they form a coherent group on molecular trees, closely related to both animals and fungi and so of interest to biologists studying their origins. In a 2008 study they emerge robustly as the sibling-group of the clade Filozoa, which includes the animals. Huldtgren et al., following x-ray tomography of microfossils of the Ediacaran Doushantuo Formation, has interpreted them as mesomycetozoan spore capsules. Terminology The name DRIP is an acronym for the first protozoa identified as members of the group, Cavalier-Smith later treated them as the class Ichthyosporea, since ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ichthyosporea
The Mesomycetozoea (or DRIP clade, or Ichthyosporea) are a small group of Opisthokonta in Eukaryota (formerly protists), mostly parasites of fish and other animals. Significance They are not particularly distinctive morphologically, appearing in host tissues as enlarged spheres or ovals containing spores, and most were originally classified in various groups as fungi, protozoa, or colorless algae. However, they form a coherent group on molecular trees, closely related to both animals and fungi and so of interest to biologists studying their origins. In a 2008 study they emerge robustly as the sibling-group of the clade Filozoa, which includes the animals. Huldtgren et al., following x-ray tomography of microfossils of the Ediacaran Doushantuo Formation, has interpreted them as mesomycetozoan spore capsules. Terminology The name DRIP is an acronym for the first protozoa identified as members of the group, Cavalier-Smith later treated them as the class Ichthyosporea, since ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amoebidiales
Amoebidiidae is a family of single-celled eukaryotes, previously thought to be zygomycete fungi belonging to the clasTrichomycetes but molecular phylogenetic analysesBenny, G. L., and O'Donnell, K. 2000. ''Amoebidium parasiticum'' is a protozoan, not a Trichomycete. ''Mycologia'' 92: 1133-1137.Ustinova, I, Krienitz, L., and Huss, V. A. R. 2000. ''Hyaloraphidium curvatum'' is not a green alga, but a lower fungus; ''Amoebidium parasiticum'' is not a fungus, but a member of the DRIPS. ''Protist'' 151: 253-262.Cafaro, M. 2005. Eccrinales (Trichomycetes) are not fungi, but a clade of protists at the early divergence of animals and fungi. Molecular Phylogenetics and Evolution 35: 21-34. place the family with the opisthokont group MesomycetozoeaMendoza L, Taylor JW, Ajello L (October 2002)"The class mesomycetozoea: a heterogeneous group of microorganisms at the animal-fungal boundary" ''Annu. Rev. Microbiol''. 56: 315–44. doi: 10.1146/annurev.micro.56.012302.160950 (= Ichthyospore ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sphaeroforma Arctica
''Sphaeroforma arctica'', is a unicellular eukaryote with a pivotal position in the tree of life. It was first isolated from the arctic marine amphipod '' Gammarus setosus''. Like other Ichthyosporeans such as ''Creolimax'' and ''Abeoforma'', ''Sphaeroforma arctica'' are spherical cells characterized with their capacity to grow into multi-nucleated coenocytes (multi-nucleates cell). However, a unique feature of ''S. arctica'', is that no obvious budding, hyphal, amoeboid, sporal or flagellated growth stages have been observed in laboratory growth conditions. Taxonomy ''Sphaeroforma'' is a member of the Ichthyosporea clade, which is the earliest branching holozoa Holozoa is a group of organisms that includes animals and their closest single-celled relatives, but excludes fungi. ''Holozoa'' is also an old name for the tunicate genus ''Distaplia''.'' Because Holozoa is a clade including all organisms mor ...n lineage. It is a key organism to understand the origin of anim ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dermocystidium
''Dermocystidium'' is a genus of cyst-forming, parasitic eukaryotes of fish, which are the causative agents of dermocystidiosis. Taxonomic History The genus ''Dermocystidium'' was described in 1907. It was previously thought to be a genus of fungal parasites, related to the Thraustochytrida and Labyrinthulida (both those groups are now considered to be stramenopiles rather than fungi). Other biologists considered it to be a sporozoan protist. It was subsequently identified as one of a group of fish parasites (the "DRIP clade") of previously uncertain affiliation, which were later identified as nonanimal, nonfungal opisthokonts, and renamed as Ichthyosporea, and after expansion as Mesomycetozoa. Parasites of crustacea (''Dermocystidium daphniae'') and molluscs (''Dermocystidium marimum'') placed in this genus have been found to be stramenopiles and reclassified as '' Lymphocystidium daphniae'' and ''Perkinsus marinus ''Perkinsus marinus'' is a species of alveolates belonging ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Opisthokont
The opisthokonts () are a broad group of eukaryotes, including both the animal and fungus kingdoms. The opisthokonts, previously called the "Fungi/Metazoa group", are generally recognized as a clade. Opisthokonts together with Apusomonadida and Breviata comprise the larger clade Obazoa. Flagella and other characteristics A common characteristic of opisthokonts is that flagellate cells, such as the sperm of most animals and the spores of the chytrid fungi, propel themselves with a single ''posterior'' flagellum. It is this feature that gives the group its name. In contrast, flagellate cells in other eukaryote groups propel themselves with one or more ''anterior'' flagella. However, in some opisthokont groups, including most of the fungi, flagellate cells have been lost. Opisthokont characteristics include synthesis of extracellular chitin in exoskeleton, cyst/spore wall, or cell wall of filamentous growth and hyphae; the extracellular digestion of substrates with osmotrophic ab ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eukaryote
Eukaryotes () are organisms whose cells have a nucleus. All animals, plants, fungi, and many unicellular organisms, are Eukaryotes. They belong to the group of organisms Eukaryota or Eukarya, which is one of the three domains of life. Bacteria and Archaea (both prokaryotes) make up the other two domains. The eukaryotes are usually now regarded as having emerged in the Archaea or as a sister of the Asgard archaea. This implies that there are only two domains of life, Bacteria and Archaea, with eukaryotes incorporated among archaea. Eukaryotes represent a small minority of the number of organisms, but, due to their generally much larger size, their collective global biomass is estimated to be about equal to that of prokaryotes. Eukaryotes emerged approximately 2.3–1.8 billion years ago, during the Proterozoic eon, likely as flagellated phagotrophs. Their name comes from the Greek εὖ (''eu'', "well" or "good") and κάρυον (''karyon'', "nut" or "kernel"). E ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protist
A protist () is any eukaryotic organism (that is, an organism whose cells contain a cell nucleus) that is not an animal, plant, or fungus. While it is likely that protists share a common ancestor (the last eukaryotic common ancestor), the exclusion of other eukaryotes means that protists do not form a natural group, or clade. Therefore, some protists may be more closely related to animals, plants, or fungi than they are to other protists. However, like the groups '' algae'', ''invertebrates'', and '' protozoans'', the biological category ''protist'' is used for convenience. Others classify any unicellular eukaryotic microorganism as a protist. The study of protists is termed protistology. History The classification of a third kingdom separate from animals and plants was first proposed by John Hogg in 1860 as the kingdom Protoctista; in 1866 Ernst Haeckel also proposed a third kingdom Protista as "the kingdom of primitive forms". Originally these also included prokaryotes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fungus
A fungus ( : fungi or funguses) is any member of the group of eukaryotic organisms that includes microorganisms such as yeasts and molds, as well as the more familiar mushrooms. These organisms are classified as a kingdom, separately from the other eukaryotic kingdoms, which by one traditional classification include Plantae, Animalia, Protozoa, and Chromista. A characteristic that places fungi in a different kingdom from plants, bacteria, and some protists is chitin in their cell walls. Fungi, like animals, are heterotrophs; they acquire their food by absorbing dissolved molecules, typically by secreting digestive enzymes into their environment. Fungi do not photosynthesize. Growth is their means of mobility, except for spores (a few of which are flagellated), which may travel through the air or water. Fungi are the principal decomposers in ecological systems. These and other differences place fungi in a single group of related organisms, named the ''Eumycota'' (''tru ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Filozoa
The Filozoa are a monophyletic grouping within the Opisthokonta. They include animals and their nearest unicellular relatives (those organisms which are more closely related to animals than to fungi or Mesomycetozoa). Three groups are currently assigned to the clade Filozoa: * Group Filasterea - recently erected to house the genera ''Ministeria'' and ''Capsaspora'' * Group Choanoflagellatea - collared flagellates * Kingdom Animalia - the animals proper Etymology From Latin ''filum'' meaning "thread" and Greek ''zōion'' meaning "animal". Phylogeny A phylogenetic tree of Filozoa and its most closely related clades: Characteristics The ancestral opisthokont cell is assumed to have possessed slender filose (thread-like) projections or 'tentacles'. In some opisthokonts (Mesomycetozoa and ''Corallochytrium'') these were lost. They are retained in Filozoa, where they are simple and non-tapering, with a rigid core of actin bundles (contrasting with the flexible, tapering and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eukaryota Tree
Eukaryotes () are organisms whose cells have a nucleus. All animals, plants, fungi, and many unicellular organisms, are Eukaryotes. They belong to the group of organisms Eukaryota or Eukarya, which is one of the three domains of life. Bacteria and Archaea (both prokaryotes) make up the other two domains. The eukaryotes are usually now regarded as having emerged in the Archaea or as a sister of the Asgard archaea. This implies that there are only two domains of life, Bacteria and Archaea, with eukaryotes incorporated among archaea. Eukaryotes represent a small minority of the number of organisms, but, due to their generally much larger size, their collective global biomass is estimated to be about equal to that of prokaryotes. Eukaryotes emerged approximately 2.3–1.8 billion years ago, during the Proterozoic eon, likely as flagellated phagotrophs. Their name comes from the Greek εὖ (''eu'', "well" or "good") and κάρυον (''karyon'', "nut" or "kernel"). Eu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Valentines
Valentine's Day, also called Saint Valentine's Day or the Feast of Saint Valentine, is celebrated annually on February 14. It originated as a Christian feast day honoring one or two early Christian martyrs named Saint Valentine and, through later folk traditions, has become a significant cultural, religious, and commercial celebration of romance and love in many regions of the world. There are a number of martyrdom stories associated with various Valentines connected to February 14, including an account of the imprisonment of Saint Valentine of Rome for ministering to Christians persecuted under the Roman Empire in the third century. According to an early tradition, Saint Valentine restored sight to the blind daughter of his jailer. Numerous later additions to the legend have better related it to the theme of love: an 18th-century embellishment to the legend claims he wrote the jailer's daughter a letter signed "Your Valentine" as a farewell before his execution; another ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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