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Oligoryzomys
''Oligoryzomys'' is a genus of rodents in the tribe Oryzomyini of family Cricetidae. Many species are known as pygmy rice rats or colilargos.Musser and Carleton, 2005 The genus is found from Mexico to Tierra del Fuego and includes approximately 17 species. In Argentina and Chile, ''Oligoryzomys longicaudatus'' and other members of the genus represent the reservoir for the hantavirus strain Andes virus (ANDV) (Wells et al., 1997; Levis et al., 1998; Cantoni et al., 2001). Taxonomy The genus ''Oligoryzomys'' is included in the subfamily Sigmodontinae of the family Cricetidae. The genus is placed in the Oryzomyini tribe, first proposed by Oldfield Thomas in the early 20th century. It includes genera that have certain dental features of the upper and lower molars and a long palate which extends past the third molars. More recently, molecular analysis and morphological data has placed the genus in Clade C, alongside ''Neacomys'', ''Microryzomys'' and ''Oreoryzomys''. Characteristics ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oligoryzomys Nigripes
''Oligoryzomys nigripes'', also known as the black-footed colilargo or the black-footed pygmy rice rat, is a rodent in the genus ''Oligoryzomys'' of family Cricetidae. Oligoryzomys nigripes is a species that has been further divided into different sister taxa throughout history. It is found in different countries in South America.Weksler, M. & Bonvicino, C.R. 2005. Taxonomy of pygmy rice rats genus ''Oligoryzomys'' Bangs, 1900 (Rodentia, Sigmodontinae) of the Brazilian Cerrado, with the description of two new species. Arquivos do Museu Nacional 63(1):119. It is a large species with long ears, dark yellow to dark brown upperparts, sharply delimited from the whitish underparts, and often a pink girdle on the chest. This species of rat spends much of its life among the trees. The karyotype is 2n = 62, FNa = 78–82. Synonym species Two other species, '' Oligoryzomys delticola'' (also known as the delta pygmy rice rat or the large colilargo) and '' Oligoryzomys eliurus'' (also kn ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sigmodontinae
The rodent subfamily Sigmodontinae includes New World rats and mice, with at least 376 species. Many authorities include the Neotominae and Tylomyinae as part of a larger definition of Sigmodontinae. When those genera are included, the species count numbers at least 508. Their distribution includes much of the New World, but the genera are predominantly South American, such as brucies. They invaded South America from Central America as part of the Great American Interchange near the end of the Miocene, about 5 million years ago. Sigmodontines proceeded to diversify explosively in the formerly isolated continent. They inhabit many of the same ecological niches that the Murinae occupy in the Old World. The "Thomasomyini" from the Atlantic Forest of Brazil are generally thought to be not especially related to the "real" Thomasomyini from the northern Andes and the Amazon rainforest. The genera ''Wiedomys'' and '' Sigmodon'' are generally placed in their own tribe, and the "phyll ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oligoryzomys Victus
''Oligoryzomys victus'', also known as the St. Vincent colilargo or St. Vincent pygmy rice rat, is a species of rodent in the genus ''Oligoryzomys'' of the oryzomyine tribe. Only one specimen is known, which was collected on Saint Vincent in the Lesser Antilles in about 1892, and it is now presumed extinct. Taxonomy The only known specimen was collected by H. H. Smith at an unknown location on Saint Vincent and later presented to the British Museum of Natural History, where it was registered as specimen BMNH 97.12.26.1. In 1898, Oldfield Thomas described the specimen as the holotype of a new species of ''Oryzomys'' which he named ''Oryzomys victus''. Although Thomas placed it close to species now placed in ''Oligoryzomys'', later compilators considered the affinities of ''O. victus'' as unknown; one study placed it in the ''Oryzomys tectus'' group (more or less = ''Oecomys''). In his 1962 study of Antillean oryzomyines, however, American paleontologist Clayton Ray reaffirmed its ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oligoryzomys Rupestris
''Oligoryzomys rupestris'' is a species of rodent in the genus ''Oligoryzomys'' of family Cricetidae. It is known only from eastern Brazil, where it has been found in several localities in the campos rupestres montane savanna ecoregion An ecoregion (ecological region) or ecozone (ecological zone) is an ecologically and geographically defined area that is smaller than a bioregion, which in turn is smaller than a biogeographic realm. Ecoregions cover relatively large areas of .... This is a small ''Oligoryzomys'' species with a gray head, a yellow-brown back and gray belly and tail. Of the two karyotypic forms described by Silva & Yonenaga-Yassuda in 1998, species 1 is probably identical to ''O. rupestris'', while the other (species 2) is closely related. Its karyotype has 2n = 46 and FNa = 52. References Mammals of Brazil Oligoryzomys Mammals described in 2005 Taxa named by Marcelo Weksler {{Oligoryzomys-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oligoryzomys Microtis
''Oligoryzomys microtis'', also known as the small-eared colilargo or small-eared pygmy rice rat, is a species of rodent in the genus ''Oligoryzomys'' of family Cricetidae. It is found in western Brazil, eastern Peru, Bolivia, and northern Paraguay. Description ''Oligoryzomys microtis'' has a total length of including a tail of . It weighs about and is the smallest species in the genus. In proportion to the head and body length, the hind feet are relatively long, being 28.5% of their length. This compares with the rather similar ''Oligoryzomys nigripes ''Oligoryzomys nigripes'', also known as the black-footed colilargo or the black-footed pygmy rice rat, is a rodent in the genus ''Oligoryzomys'' of family Cricetidae. Oligoryzomys nigripes is a species that has been further divided into differen ...'' where the proportion is 24.5%. The ears are small and densely furred inside. The cheeks may be grey or orangeish-brown. The back is brownish and the underparts are whitish or gr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
