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Sooretamys Angouya
''Sooretamys angouya'', also known as the rat-headed rice rat,Duff and Lawson, 2004 and Paraguayan rice rat, is a rodent species from South America.Musser and Carleton, 2005 It is found in northeastern Argentina, southern Brazil and Paraguay in forested areas within the Atlantic Forest and cerrado. Since 2006, it has been classified as the only species in the genus ''Sooretamys''; previously, it was included in the genus ''Oryzomys''. Its taxonomic history has been complex, with the names ''Oryzomys angouya'', ''Oryzomys buccinatus'', and ''Oryzomys ratticeps'' in use for various parts of the species at different times. Some variation in its karyotype A karyotype is the general appearance of the complete set of chromosomes in the cells of a species or in an individual organism, mainly including their sizes, numbers, and shapes. Karyotyping is the process by which a karyotype is discerned by de ... has been reported, with 2n = 80 to 82 and FN = 88 to 90. References Literatu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Marcelo Weksler
Marcelo is a given name, the Spanish and Portuguese form of Marcellus. Marcelo may refer to: Given name * Marcelo Costa de Andrade (born 1967), Brazilian serial killer, rapist, and necrophile * Marcelo Arriagada (born 1973), Chilean road cyclist * Marcelo Barovero (born 1984), Argentine football goalkeeper *Marcelo Barticciotto (born 1967), Argentine-born Chilean former footballer and manager *Marcelo Bordon (born 1976), Brazilian footballer *Marcelo Cabo (born 1966), Brazilian football manager *Marcelo Carrusca (born 1983), Argentine-Australian professional footballer *Marcelo Cassaro (born 1970), Brazilian author of comics * Marcelo Chamusca (born 1966), Brazilian professional football manager and former player *Marcelo Chierighini (born 1991), Brazilian competitive swimmer *Marcelo Cirino (born 1992), Brazilian footballer *Marcelo D'Andrea, Argentine film actor * Marcelo Del Debbio (born 1974), Brazilian architect and writer *Marcelo Demoliner (born 1989), Brazilian tennis pla ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Genus
Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In binomial nomenclature, the genus name forms the first part of the binomial species name for each species within the genus. :E.g. ''Panthera leo'' (lion) and ''Panthera onca'' (jaguar) are two species within the genus ''Panthera''. ''Panthera'' is a genus within the family Felidae. The composition of a genus is determined by taxonomy (biology), taxonomists. The standards for genus classification are not strictly codified, so different authorities often produce different classifications for genera. There are some general practices used, however, including the idea that a newly defined genus should fulfill these three criteria to be descriptively useful: # monophyly – all descendants of an ancestral taxon are grouped together (i.e. Phylogeneti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Taxa Named By Marcelo Weksler
In biology, a taxon (back-formation from ''taxonomy''; : taxa) is a group of one or more populations of an organism or organisms seen by taxonomists to form a unit. Although neither is required, a taxon is usually known by a particular name and given a particular ranking, especially if and when it is accepted or becomes established. It is very common, however, for taxonomists to remain at odds over what belongs to a taxon and the criteria used for inclusion, especially in the context of rank-based (" Linnaean") nomenclature (much less so under phylogenetic nomenclature). If a taxon is given a formal scientific name, its use is then governed by one of the nomenclature codes specifying which scientific name is correct for a particular grouping. Initial attempts at classifying and ordering organisms (plants and animals) were presumably set forth in prehistoric times by hunter-gatherers, as suggested by the fairly sophisticated folk taxonomies. Much later, Aristotle, and later still ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oryzomyini
Oryzomyini is a tribe of rodents in the subfamily Sigmodontinae of the family Cricetidae. It includes about 120 species in about thirty genera,Weksler et al., 2006, table 1 distributed from the eastern United States to the southernmost parts of South America, including many offshore islands. It is part of the clade Oryzomyalia, which includes most of the South American Sigmodontinae. The name ''Oryzomyini'' derives from that of its type genus, '' Oryzomys'', which means "rice rat" or "rice mouse". Many species are also known as rice rats. Taxonomy Contents of Oryzomyini An oryzomyine group was first envisaged by Oldfield Thomas in the early 20th century. He defined it to include pentalophodont species, which have a mesoloph(id) on the upper and lower molars, with a long palate (extending past the third molars). Thomas included '' Oligoryzomys'', '' Oecomys'', and '' Oryzomys'' (which included many species now in other genera), as well as '' Rhagomys'', which is currently classi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Karyotype
A karyotype is the general appearance of the complete set of chromosomes in the cells of a species or in an individual organism, mainly including their sizes, numbers, and shapes. Karyotyping is the process by which a karyotype is discerned by determining the chromosome complement of an individual, including the number of chromosomes and any abnormalities. A karyogram or idiogram is a graphical depiction of a karyotype, wherein chromosomes are generally organized in pairs, ordered by size and position of centromere for chromosomes of the same size. Karyotyping generally combines light microscopy and photography in the metaphase of the cell cycle, and results in a photomicrographic (or simply micrographic) karyogram. In contrast, a schematic karyogram is a designed graphic representation of a karyotype. In schematic karyograms, just one of the sister chromatids of each chromosome is generally shown for brevity, and in reality they are generally so close together that they look as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ploidy
Ploidy () is the number of complete sets of chromosomes in a cell, and hence the number of possible alleles for autosomal and pseudoautosomal genes. Here ''sets of chromosomes'' refers to the number of maternal and paternal chromosome copies, respectively, in each homologous chromosome pair—the form in which chromosomes naturally exist. Somatic cells, tissues, and individual organisms can be described according to the number of sets of chromosomes present (the "ploidy level"): monoploid (1 set), diploid (2 sets), triploid (3 sets), tetraploid (4 sets), pentaploid (5 sets), hexaploid (6 sets), heptaploid or septaploid (7 sets), etc. The generic term polyploid is often used to describe cells with three or more sets of chromosomes. Virtually all sexually reproducing organisms are made up of somatic cells that are diploid or greater, but ploidy level may vary widely between different organisms, between different tissues within the same organism, and at different stages in an o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Karyotype
A karyotype is the general appearance of the complete set of chromosomes in the cells of a species or in an individual organism, mainly including their sizes, numbers, and shapes. Karyotyping is the process by which a karyotype is discerned by determining the chromosome complement of an individual, including the number of chromosomes and any abnormalities. A karyogram or idiogram is a graphical depiction of a karyotype, wherein chromosomes are generally organized in pairs, ordered by size and position of centromere for chromosomes of the same size. Karyotyping generally combines light microscopy and photography in the metaphase of the cell cycle, and results in a photomicrographic (or simply micrographic) karyogram. In contrast, a schematic karyogram is a designed graphic representation of a karyotype. In schematic karyograms, just one of the sister chromatids of each chromosome is generally shown for brevity, and in reality they are generally so close together that they look as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Taxonomy (biology)
In biology, taxonomy () is the science, scientific study of naming, defining (Circumscription (taxonomy), circumscribing) and classifying groups of biological organisms based on shared characteristics. Organisms are grouped into taxon, taxa (singular: taxon), and these groups are given a taxonomic rank; groups of a given rank can be aggregated to form a more inclusive group of higher rank, thus creating a taxonomic hierarchy. The principal ranks in modern use are domain (biology), domain, kingdom (biology), kingdom, phylum (''division'' is sometimes used in botany in place of ''phylum''), class (biology), class, order (biology), order, family (biology), family, genus, and species. The Swedish botanist Carl Linnaeus is regarded as the founder of the current system of taxonomy, having developed a ranked system known as Linnaean taxonomy for categorizing organisms. With advances in the theory, data and analytical technology of biological systematics, the Linnaean system has transfo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oryzomys
''Oryzomys'' is a genus of semiaquatic rodents in the tribe Oryzomyini living in southern North America and far northern South America. It includes eight species, two of which—the marsh rice rat (''O. palustris'') of the United States and ''Oryzomys couesi, O. couesi'' of Mexico and Central America—are widespread; the six others have more restricted distributions. The species have had eventful Taxonomy (biology), taxonomic histories, and most species were at one time included in the marsh rice rat; additional species may be recognized in the future. The name ''Oryzomys'' was established in 1857 by Spencer Fullerton Baird for the marsh rice rat and was soon applied to over a hundred species of American rodents. Subsequently, the genus gradually became more narrowly defined until its current contents were established in 2006, when ten new genera were established for species previously placed in ''Oryzomys''. Species of ''Oryzomys'' are medium-sized rats with long, coa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Monotypic Taxon
In biology, a monotypic taxon is a taxonomic group (taxon) that contains only one immediately subordinate taxon. A monotypic species is one that does not include subspecies or smaller, infraspecific taxa. In the case of Genus, genera, the term "unispecific" or "monospecific" is sometimes preferred. In botanical nomenclature, a monotypic genus is a genus in the special case where a genus and a single species are simultaneously described. Theoretical implications Monotypic taxa present several important theoretical challenges in biological classification. One key issue is known as "Gregg's Paradox": if a single species is the only member of multiple hierarchical levels (for example, being the only species in its genus, which is the only genus in its family), then each level needs a distinct definition to maintain logical structure. Otherwise, the different taxonomic ranks become effectively identical, which creates problems for organizing biological diversity in a hierarchical o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Johann Fischer Von Waldheim
Gotthelf Fischer von Waldheim (; 13 October 1771 – 18 October 1853) was a Electorate of Saxony, Saxon anatomist, entomologist and paleontologist. Fischer was born as Gotthilf Fischer in Waldheim, Saxony, Waldheim, Saxony, the son of a linen weaver. He studied medicine at Leipzig. He travelled to Vienna and Paris with his friend Alexander von Humboldt and studied under Georges Cuvier. He took up a professorship at Mainz, and then in 1804, became Professor of Natural History and Director of the Demidov Natural History Museum at the Moscow State University, Moscow University. In August 1805, he founded the Société Impériale des Naturalistes de Moscou. Fischer was elected a Foreign Honorary Member of the American Academy of Arts and Sciences in 1812 and a member of the American Philosophical Society in 1818. Fischer was mainly engaged in the classification of invertebrates, the result of which was his ''Entomographia Imperii Rossici'' (1820–1851). He also spent time study ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cerrado
The Cerrado () is a vast ecoregion of Tropics, tropical savanna in central Brazil, being present in the states of Goiás, Mato Grosso do Sul, Mato Grosso, Tocantins, Maranhão, Piauí, Bahia, Minas Gerais, São Paulo (state), São Paulo, Paraná (state), Paraná and the Federal District (Brazil), Federal District. The core areas of the Cerrado biome are the Brazilian highlands – the ''Planalto''. The main habitat types of the Cerrado consist of forest savanna, wooded savanna, park savanna and grass, gramineous-woody savanna. The Cerrado also includes savanna wetlands and gallery forests. The second largest of Biomes in Brazil, Brazil's major habitat types, after the Amazon rainforest, Amazonian rainforest, the Cerrado accounts for a full 21 percent of the country's land area (extending marginally into Paraguay and Bolivia). About 75% of the Cerrado’s 2 million km2 is privately owned. Vast amounts of research have shown that the Cerrado is one of the richest of all tropi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
