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Oryzomyines
Oryzomyini is a tribe (taxonomy), 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 List of mammals of the United States, United States to the southernmost parts of List of mammals of South America, 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 molar (tooth), molars, with a long palate (extending past the third molars). Thomas included ''Oligoryzomys'', ''Oecomys'', and ''Oryzomys'' (w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Marsh Rice Rat
The marsh rice rat (''Oryzomys palustris'') is a semiaquatic North American rodent in the family Cricetidae. It usually occurs in wetland habitats, such as swamps and salt marshes. It is found mostly in the eastern and southern United States, from New Jersey and Kansas south to Florida and northeasternmost Tamaulipas, Mexico; its range previously extended further west and north, where it may have been a commensalism, commensal in corn-cultivating communities. Weighing about , the marsh rice rat is a medium-sized rodent that resembles the common black rat, black and brown rat. The upperparts are generally gray-brown, but are reddish in many Florida populations. The feet show several specializations for life in the water. The skull is large and flattened, and is short at the front. John Bachman discovered the marsh rice rat in 1816, and it was formally described in 1837. Several subspecies have been described since the 1890s, mainly from Florida, but disagreement exists over their ... [...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] |
Lundomys
''Lundomys molitor'', also known as Lund's amphibious ratMusser and Carleton, 2005, p. 1124 or the greater marsh rat, is a semiaquatic rat species from southeastern South America. Its distribution is now restricted to Uruguay and nearby Rio Grande do Sul, Brazil, but it previously ranged northward into Minas Gerais, Brazil, and southward into eastern Argentina. The Argentine form may have been distinct from the living form from Brazil and Uruguay. ''L. molitor'' is a large rodent, with the head and body length averaging , characterized by a long tail, large hindfeet, and long and dense fur. It builds nests above the water, supported by reeds, and it is not currently threatened. Its external morphology (biology), morphology is similar to that of ''Holochilus brasiliensis'', and over the course of its complex taxonomy (biology), taxonomic history it has been confused with that species, but other features support its placement in a distinct genus, ''Lundomys''. Within the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Drymoreomys
''Drymoreomys'' is a rodent genus in the tribe Oryzomyini that lives in the Atlantic Forest of Brazil. The single species, ''D. albimaculatus'', is known only from the states of São Paulo (state), São Paulo and Santa Catarina (state), Santa Catarina and was not named until 2011. It lives in the humid forest on the eastern slopes of the Serra do Mar and perhaps reproduces year-round. Although its range is relatively large and includes some protected areas, it is patchy and threatened, and the discoverers recommend that the animal be considered "Near Threatened" on the IUCN Red List. Within Oryzomyini, ''Drymoreomys'' appears to be most closely related to ''Eremoryzomys'' from the Andes of Peru, a biogeography, biogeographically unusual relationship, in that the two populations are widely separated and each is adapted to an arid or a moist environment. With a body mass of , ''Drymoreomys'' is a medium-sized rodent with long fur that is orange to reddish-buff (colour), buff a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carletonomys
''Carletonomys cailoi'' is an extinct rodent from the Pleistocene (Ensenadan) of Buenos Aires Province, Argentina. Although known only from a single maxilla (upper jaw) with the first molar, its features are so distinctive that it is placed in its own genus, ''Carletonomys''. Discovered in 1998 and formally described in 2008, it is part of a well-defined group of oryzomyine rodents that also includes ''Holochilus'', ''Noronhomys'', ''Lundomys'', and ''Pseudoryzomys''. This group is characterized by progressive semiaquatic specializations and a reduction in the complexity of molar morphology. The single known molar is high-crowned (hypsodont) and flat-crowned (planar) and is distinctive in lacking the ridge that connects the front to the middle part of the molar, the anterior mure, and in the configuration of another ridge, the mesoloph. ''Carletonomys'' was probably herbivorous and lived in a wet habitat. Taxonomy ''Carletonomys cailoi'' was discovered in 1998 in a silt deposit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Noronhomys
''Noronhomys vespuccii'', also known as Vespucci's rodent, is an extinction, extinct rat species from the islands of Fernando de Noronha off northeastern List of mammals of Brazil, Brazil. Italian explorer Amerigo Vespucci may have seen it on a visit to Fernando de Noronha in 1503, but it subsequently became extinct, perhaps because of the exotic rats and mice introduced by the first explorers of the island. Numerous but fragmentary fossil remains of the animal, of uncertain but probably Holocene age, were discovered in 1973 and described in 1999. ''Noronhomys vespuccii'' was a fairly large rodent, larger than the black rat (''Rattus rattus''). A member of the family Cricetidae and subfamily Sigmodontinae, it shares several distinctive characters with ''Holochilus'' and related genera within the tribe Oryzomyini, including high-crowned molars with simplified crown features and the presence of several ridges on the skull which help anchor the chewing muscles. Although a suite of t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eremoryzomys
''Eremoryzomys polius'', also known as the gray rice rat or the Marañon oryzomys,Musser and Carleton, 2005, p. 1153 is a rodent species in the tribe Oryzomyini of the family Cricetidae. Discovered in 1912 and first described in 1913 by Wilfred Osgood, it was originally placed in ''Oryzomys'' and named ''Oryzomys polius''. In 2006, a cladistic analysis found that it was not closely related to ''Oryzomys'' in the strict sense or to any other oryzomyine then known, so that it is now placed in its own genus, ''Eremoryzomys''. The Brazilian genus ''Drymoreomys'', named in 2011, is probably the closest relative of ''Eremoryzomys''. ''Eremoryzomys'' has a limited distribution in the dry upper valley of the Marañón River in central Peru, but may yet contain more than one species. A large, long-tailed rice rat, with head and body length of , ''E. polius'' has gray fur and short ears. There are well-developed ungual tufts of hair on the hindfeet. Females have eight mammae. The ros ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Agathaeromys
''Agathaeromys'' is an extinct genus of oryzomyine rodents from the Pleistocene of Bonaire, Netherlands Antilles. Two species are known, which differ in size and some details of tooth morphology. The larger ''A. donovani'', the type species, is known from hundreds of teeth that are probably 900,000 to 540,000 years old, found in four localities. ''A. praeuniversitatis'', the smaller species, is known from 35 teeth found in a single fossil site, which is probably 540,000 to 230,000 years old. Although material of ''Agathaeromys'' was first described in 1959, the genus was not formally named and diagnosed until 2010. It probably belongs to "clade D" within the oryzomyine group, together with many other island-dwelling species. The molars of both species possess several accessory crests in addition to the main cusps. In addition to some differences in features of the chewing surface of the molars, ''A. donovani'' has more roots on its lower molars than does ''A ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cerradomys
''Cerradomys'' is a genus of oryzomyine rodents from eastern Bolivia, Paraguay, and central Brazil found in cerrado, Caatinga and Gran Chaco habitats. The species in this genus have historically been placed in ''Oryzomys'', but according to cladistic research, they are not more closely related to the type species of ''Oryzomys'' than species in some other genera are. Its sister group may be a clade of oryzomyines living in open or aquatic habitats, comprising, among others, ''Aegialomys'', ''Nectomys'' and ''Sigmodontomys''. ''Sooretamys angouya'', also formerly in ''Oryzomys'', is another relative; it has been placed in the same group as the species of ''Cerradomys'' in the past. The generic name ''Cerradomys'' is a compound of the word "Cerrado" and the Ancient Greek ''mys'' "mouse" and therefore means "Cerrado mouse". The dorsal pelage is brownish, the ventral pelage, greyish. It has small ears and a relatively long tail. There are crowns of hair on the hindfeet at the bases ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Melanomys
''Melanomys'' is a genus of rodent in the tribe Oryzomyini of family Cricetidae, which is distributed in northern South America and adjacent Central America. It contains three species, two of which—''Melanomys robustulus'' and ''Melanomys zunigae''—have limited distributions. The third, ''Melanomys caliginosus ''Melanomys caliginosus'', also known as the dusky melanomysMusser and Carleton, 2005 or dusky rice rat, is a species of rodent in the genus '' Melanomys'' of family Cricetidae. It is found from Central America, in Honduras, Nicaragua, Costa Rica ...'', is more widely distributed, but may be a species complex. References Rodent genera Taxa named by Oldfield Thomas Taxonomy articles created by Polbot {{Sigmodontinae-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nephelomys
''Nephelomys'' is a genus of South American oryzomyine rodents found in the Andes from Bolivia to Venezuela, with a westward extension into the mountains of Costa Rica. Its generic name is derived from the Ancient Greek word ''nephelê'' "mist", referring to the cloud forest habitat of the members of the genus. The species in this genus have historically been placed in ''Oryzomys'', but in 2006, Brazilian zoologist Marcelo Weksler and coworkers described it as a separate genus, because it is not closely related to the type species of ''Oryzomys''.Weksler, 2006 They are most closely related to other members of clade B, including '' Euryoryzomys'', '' Transandinomys'', ''Hylaeamys'', ''Oecomys'', and ''Handleyomys'', with some weak evidence supporting a sister-group relationship to ''Transandinomys''.Weksler et al., 2006, p. 20 ''Oryzomys'' appears in a different part of the oryzomyine evolutionary radiation, perhaps close to ''Holochilus'' and related genera. ''Nephelomys'' spec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nectomys
''Nectomys'' is a genus of rodent in the tribe Oryzomyini of family Cricetidae. Musser and Carleton, 2005. It is closely related to '' Amphinectomys'' and was formerly considered congeneric with '' Sigmodontomys''. It consists of five species, which are allopatrically distributed across much of South America: '' Nectomys grandis'' in montane Colombia; '' Nectomys palmipes'' on Trinidad and in nearby Venezuela, '' Nectomys apicalis'' in the western margins of the Amazon biome, ''Nectomys rattus'' in much of Amazonia, and '' Nectomys squamipes'' in the Atlantic Forest of Brazil. These species are generally semiaquatic In biology, being semi-aquatic refers to various macroorganisms that live regularly in both aquatic and terrestrial environments. When referring to animals, the term describes those that actively spend part of their daily time in water (in ..., are normally found near water, and are commonly called water rats. Notes References Literature cited * ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
