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Subsquamosal Fenestra
In some rodents, the subsquamosal fenestra is an opening between two parts of the squamosal bone, at the back of the skull. It can be seen in lateral view. Most Oryzomyini have the fenestra, but some species, including those in the genera ''Nectomys'', ''Sigmodontomys'', and ''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 ...'' among others, lack it.Weksler, 2006, pp. 38–39 References {{reflist Literature cited *Weksler, M. 2006Phylogenetic relationships of oryzomyine rodents (Muroidea: Sigmodontinae): separate and combined analyses of morphological and molecular data Bulletin of the American Museum of Natural History 296:1–149. Rodent anatomy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rodent
Rodents (from Latin , 'to gnaw') are mammals of the order Rodentia (), which are characterized by a single pair of continuously growing incisors in each of the upper and lower jaws. About 40% of all mammal species are rodents. They are native to all major land masses except for New Zealand, Antarctica, and several oceanic islands, though they have subsequently been introduced to most of these land masses by human activity. Rodents are extremely diverse in their ecology and lifestyles and can be found in almost every terrestrial habitat, including human-made environments. Species can be arboreal, fossorial (burrowing), saltatorial/richochetal (leaping on their hind legs), or semiaquatic. However, all rodents share several morphological features, including having only a single upper and lower pair of ever-growing incisors. Well-known rodents include mice, rats, squirrels, prairie dogs, porcupines, beavers, guinea pigs, and hamsters. Rabbits, hares, and pikas, whose i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Squamosal Bone
The squamosal is a skull bone found in most reptiles, amphibians, and birds. In fishes, it is also called the pterotic bone. In most tetrapods, the squamosal and quadratojugal bones form the cheek series of the skull. The bone forms an ancestral component of the dermal roof and is typically thin compared to other skull bones. The squamosal bone lies ventral to the temporal series and otic notch, and is bordered anteriorly by the postorbital. Posteriorly, the squamosal articulates with the quadrate and pterygoid bones. The squamosal is bordered anteroventrally by the jugal and ventrally by the quadratojugal. Function in reptiles In reptiles, the quadrate and articular bones of the skull articulate to form the jaw joint. The squamosal bone lies anterior to the quadrate bone. Anatomy in synapsids Non-mammalian synapsids In non-mammalian synapsids, the jaw is composed of four bony elements and referred to as a quadro-articular jaw because the joint is between the articular an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Skull
The skull is a bone protective cavity for the brain. The skull is composed of four types of bone i.e., cranial bones, facial bones, ear ossicles and hyoid bone. However two parts are more prominent: the cranium and the mandible. In humans, these two parts are the neurocranium and the viscerocranium ( facial skeleton) that includes the mandible as its largest bone. The skull forms the anterior-most portion of the skeleton and is a product of cephalisation—housing the brain, and several sensory structures such as the eyes, ears, nose, and mouth. In humans these sensory structures are part of the facial skeleton. Functions of the skull include protection of the brain, fixing the distance between the eyes to allow stereoscopic vision, and fixing the position of the ears to enable sound localisation of the direction and distance of sounds. In some animals, such as horned ungulates (mammals with hooves), the skull also has a defensive function by providing the mount (on the front ... [...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 classified ... [...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, semiaquatic can refer to various types of animals that spend part of their time in water, or plants that naturally grow partially submerged in water. Examples are given below. Semiaquatic animals Semiaquatic animals include: * Verte ..., are normally found near water, and are commonly called water rats. Notes References Literature cited * Rodent g ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sigmodontomys
''Sigmodontomys'' is a genus of rodent in the tribe Oryzomyini of family Cricetidae. It is related to ''Nectomys'' and ''Melanomys'' and used to be included in ''Nectomys''. It includes two species, ''Sigmodontomys alfari'' and the much rarer ''Sigmodontomys aphrastus'', but whether these are indeed each other's closest relatives is uncertain.Weksler, 2006 References Literature cited *Musser, G.G. and Carleton, M.D. 2005. Superfamily Muroidea. Pp. 894–1531 in Wilson, D.E. and Reeder, D.M. (eds.)Mammal Species of the World: a taxonomic and geographic reference. 3rd ed Baltimore: The Johns Hopkins University Press, 2 vols., 2142 pp. *Weksler, M. 2006Phylogenetic relationships of oryzomyine rodents (Muroidea: Sigmodontinae): separate and combined analyses of morphological and molecular data Bulletin of the American Museum of Natural History 296:1–149. Sigmodontomys, Rodent genera Taxa named by Joel Asaph Allen Taxonomy articles created by Polbot {{Sigmodontina ... [...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] |
