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Allantocystidae
''Allantocystis'' is a genus in the family ''Allantocystidae''. Its only species is ''Allantocystis dasyhelei'', a gregarine parasite of the larval biting midge '' Dasyhelea obscura''. Description ''A. dasyhelei'' are found in the midgut of the host larva as 70 μm by 20 μm forms, running parallel to the host body. They are unique from other Gregarine parasites in that their cysts are elongated, rather than spherical. Taxonomy ''A. dasyhelei'' is the only species in the genus ''Allantocystis''. ''Allantocystis'' is the only genus in the family ''Allantocistidae''. History ''A. dasyhelei'' was described by David Keilin David Keilin FRS (21 March 1887 – 27 February 1963) was a Jewish scientist focusing mainly on entomology. Background and education He was born in Moscow in 1887 and his family returned to Warsaw early in his youth. He did not attend scho ... in 1920 from larval biting midges he found in the decomposing sap of infected Elm and Horse-chestnut tr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aseptatorina
''Aseptatorina'' is a suborder of parasitic alveolates of the phylum Apicomplexia Taxonomy There are eleven families recognised in this suborder. There are ~400 species in these families. Five families — ''Allantocystidae'', ''Diplocystidae'', ''Enterocystidae'', ''Ganymedidae'' and ''Schaudinnellidae'' — have only one genus. ''Aikinetocystidae'' has two genera. Two families in this suborder — ''Ganymedidae'' and ''Thiriotiidae'' — infect crustacean Crustaceans (Crustacea, ) form a large, diverse arthropod taxon which includes such animals as decapods, seed shrimp, branchiopods, fish lice, krill, remipedes, isopods, barnacles, copepods, amphipods and mantis shrimp. The crustacean group can ...s. The taxonomy of this suborder may be in need of revision as it has been shown based on SSU 18S rDNA sequences that four families — ''Ganymedidae'' from the Aseptatorina and ''Cephalolobidae'', ''Porosporidae'' and ''Uradiophoridae'' from the Septatorina appear to form ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eukaryota
Eukaryotes () are organisms whose Cell (biology), cells have a cell nucleus, 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-domain system, 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), Asgard archaea. This implies that there are only Two-domain system, 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 (ecology), 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 cell, flagellated phagotrophs. The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
SAR Supergroup
The SAR supergroup, also just SAR or Harosa, is a clade that includes stramenopiles (heterokonts), alveolates, and Rhizaria. The name is an acronym derived from the first letters of each of these clades; it has been alternatively spelled "RAS". The term "Harosa" (at the subkingdom level) has also been used. The SAR supergroup is a node-based taxon. Note that as a formal taxon, "Sar" has only its first letter capitalized, while the earlier abbreviation, SAR, retains all uppercase letters. Both names refer to the same group of organisms, unless further taxonomic revisions deem otherwise. Members of the SAR supergroup were once included under the separate supergroups Chromalveolata (Chromista and Alveolata) and Rhizaria, until phylogenetic studies confirmed that stramenopiles and alveolates diverged with Rhizaria. This apparently excluded haptophytes and cryptomonads, leading Okamoto ''et al.'' (2009) to propose the clade Hacrobia to accommodate them. Phylogeny Based on a compi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Apicomplexa
The Apicomplexa (also called Apicomplexia) are a large phylum of parasitic alveolates. Most of them possess a unique form of organelle that comprises a type of non-photosynthetic plastid called an apicoplast, and an apical complex structure. The organelle is an adaptation that the apicomplexan applies in penetration of a host cell. The Apicomplexa are unicellular and spore-forming. All species are obligate endoparasites of animals, except '' Nephromyces'', a symbiont in marine animals, originally classified as a chytrid fungus. Motile structures such as flagella or pseudopods are present only in certain gamete stages. The Apicomplexa are a diverse group that includes organisms such as the coccidia, gregarines, piroplasms, haemogregarines, and plasmodia. Diseases caused by Apicomplexa include: * Babesiosis (''Babesia'') * Malaria (''Plasmodium'') * Cryptosporidiosis (''Cryptosporidium parvum'') * Cyclosporiasis (''Cyclospora cayetanensis'') * Cystoisosporiasis (''Cystoisosp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Conoidasida
Conoidasida is a class of parasitic alveolates in the phylum Apicomplexa. The class was defined in 1988 by Levine and contains two subclasses – the coccidia and the gregarines. All members of this class have a complete, hollow, truncated conoid. Gregarines tend to parasitize invertebrates with the mature gamonts being extracellular, the coccidia mostly infect vertebrates and have intracellular gamonts. Description A conoid is found in most species and when present forms complete but truncated cone. Sexual and asexual reproduction are present in life cycle of all species. Each zygote normally forms an oocyst wall within which it undergoes meiosis. This is sometimes followed by mitosis. This process of sporogony produces mobile vermiform infectious sporozoites. Multiple mitotic divisions ( schizogony) also occur during merogony of the feeding stages (trophozoites) and during gametogony. Motility Microgametes of some species are flagellated. Locomotion of other gametes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gregarinasina
The gregarines are a group of Apicomplexan alveolates, classified as the Gregarinasina or Gregarinia. The large (roughly half a millimeter) parasites inhabit the intestines of many invertebrates. They are not found in any vertebrates. However, gregarines are closely related to both ''Toxoplasma'' and ''Plasmodium'', which cause toxoplasmosis and malaria, respectively. Both protists use protein complexes similar to those that are formed by the gregarines for gliding motility and invading target cells. This makes them excellent models for studying gliding motility with the goal of developing treatment options for toxoplasmosis and malaria. Thousands of different species of gregarines are expected to be found in insects, and 99% of these gregarines still need to be described. Each insect can be the host of multiple species. One of the most studied gregarines is ''Gregarina garnhami''. In general, gregarines are regarded as very successful parasites, as their hosts are spread over the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eugregarinorida
The ''Eugregarinorida'' are the most large and diverse order of gregarines — parasitic protists belonging to the phylum Apicomplexa. Eugregarines are found in marine, freshwater and terrestrial habitats. These species possess large trophozoites that are significantly different in morphology and behavior from the sporozoites. This taxon contains most of the known gregarine species. These protozoa are common parasites of many invertebrates including insects and polychete worms. Taxonomy Eugregarinorida has three recognised suborders: Aseptatorina, Blastogregarinorina and Septatorina. The intestinal eugregarines are separated into septate — suborder Septatina — and aseptate — suborder Aseptatina — depending on whether the trophozoite is superficially divided by a transverse septum. The marine gregarines are the most poorly studied members of this order. The eugregarines have been classified into 27 families with ~244 genera, 14 of which have more than 25 species each. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
David Keilin
David Keilin FRS (21 March 1887 – 27 February 1963) was a Jewish scientist focusing mainly on entomology. Background and education He was born in Moscow in 1887 and his family returned to Warsaw early in his youth. He did not attend school until age ten due to ill health and asthma. Only seven years later, in 1904, he enrolled in the University of Liège. He later studied at Magdalene College, Cambridge, and became a British citizen. Career Keilin became research assistant to George Nuttall, first Quick Professor of Biology at the University of Cambridge, in 1915, and spent the rest of his career there, succeeding Nuttall as Quick Professor and director of the Molteno Institute in 1931. He retired in 1952. He made extensive contributions to entomology and parasitology during his career. He published thirty-nine papers between 1914 and 1923 on the reproduction of lice, the life-cycle of the horse bot-fly, the respiratory adaptations in fly larvae, and other subjects. He ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gregarine
The gregarines are a group of Apicomplexan alveolates, classified as the Gregarinasina or Gregarinia. The large (roughly half a millimeter) parasites inhabit the intestines of many invertebrates. They are not found in any vertebrates. However, gregarines are closely related to both ''Toxoplasma'' and ''Plasmodium'', which cause toxoplasmosis and malaria, respectively. Both protists use protein complexes similar to those that are formed by the gregarines for gliding motility and invading target cells. This makes them excellent models for studying gliding motility with the goal of developing treatment options for toxoplasmosis and malaria. Thousands of different species of gregarines are expected to be found in insects, and 99% of these gregarines still need to be described. Each insect can be the host of multiple species. One of the most studied gregarines is ''Gregarina garnhami''. In general, gregarines are regarded as very successful parasites, as their hosts are spread over the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dasyhelea Obscura
''Dasyhelea'' is a genus of biting midges and the only genus of its subfamily, the Dasyheleinae. Larvae of species in this genus are characterized by an anal segment with retractile posterior prolegs. Larvae are aquatic and adults do not feed on vertebrate blood, nor do they prey on other insects. They take nectar only, an unusual feeding behavior within the Ceratopogonidae Ceratopogonidae is a family of flies commonly known as no-see-ums, or biting midges, generally in length. The family includes more than 5,000 species, distributed worldwide, apart from the Antarctic and the Arctic. Ceratopogonidae are holomet .... References * Elson-Harris, M.M. 1990. Keys to the immature stages of some Australian Ceratopogonidae. ''Journal of the Australian Entomological Society'' 29: 267-275. * Mullen, G.R. and L.J. Hribar. 1988. Biology and feeding behavior of ceratopogonid larvae (Diptera: Ceratopogonidae) in North America. ''Bulletin of the Society for Vector Ecology'' 13: 60-81. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Micrometre
The micrometre ( international spelling as used by the International Bureau of Weights and Measures; SI symbol: μm) or micrometer (American spelling), also commonly known as a micron, is a unit of length in the International System of Units (SI) equalling (SI standard prefix "micro-" = ); that is, one millionth of a metre (or one thousandth of a millimetre, , or about ). The nearest smaller common SI unit is the nanometre, equivalent to one thousandth of a micrometre, one millionth of a millimetre or one billionth of a metre (). The micrometre is a common unit of measurement for wavelengths of infrared radiation as well as sizes of biological cells and bacteria, and for grading wool by the diameter of the fibres. The width of a single human hair ranges from approximately 20 to . The longest human chromosome, chromosome 1, is approximately in length. Examples Between 1 μm and 10 μm: * 1–10 μm – length of a typical bacterium * 3–8 μm – width of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
