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Heteromyinae
Heteromyinae is a subfamily of rodents in the family Heteromyidae, commonly known as spiny pocket mice. It contains a single extant genus, '' Heteromys'', as well as the extinct genera ''Diprionomys'' and ''Metaliomys''. ''Heteromys'' was recently enlarged by inclusion of the members of formerly recognized heteromyine genus ''Liomys'', which was found to be paraphyletic. Taxonomy Heteromyinae is the sister group In phylogenetics, a sister group or sister taxon, also called an adelphotaxon, comprises the closest relative(s) of another given unit in an evolutionary tree. Definition The expression is most easily illustrated by a cladogram: Taxon A and ... of Perognathinae; the two are estimated to have split about 22-23 million years ( Ma) ago. The most recent common ancestor of extant heteromyines is thought to have lived 12-15 Ma ago; the basal species in the subfamily is '' H. salvini''. References Heteromyidae Taxa named by John Edward Gray Mammal subfamil ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heteromys
''Heteromys'' is a genus of rodents in the family Heteromyidae, commonly known as spiny pocket mice. It is the only extant genus in the subfamily Heteromyinae which also includes the extinct genera '' Diprionomys'' and ''Metaliomys''. ''Heteromys'' was recently enlarged by inclusion of the members of formerly recognized heteromyine genus ''Liomys'', which was found to be paraphyletic. Distribution Heteromyines are distributed from southern Texas to Ecuador and Venezuela, and include all but one of the castorimorph species of South America. Like all of South America's other non-caviomorph rodents, they arrived in the continent relatively recently as part of the Great American Interchange. They inhabit mainly forests; some are also found in scrubland. Taxonomy The genus ''Heteromys'' comprises the following species of spiny pocket mice: * Panamanian spiny pocket mouse (''H. adspersus'') * Trinidad spiny pocket mouse (''H. anomalus'') * Southern spiny pocket mouse (''H. austr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heteromyidae
Heteromyidae is a family of rodents consisting of kangaroo rats, kangaroo mice, pocket mice and spiny pocket mice. Most heteromyids live in complex burrows within the deserts and grasslands of western North America, though species within the genus '' Heteromys'' are also found in forests and their range extends down as far as northern South America. They feed mostly on seeds and other plant parts, which they carry in their fur-lined cheek pouches to their burrows. Although they are very different in physical appearance, the closest relatives of the heteromyids are pocket gophers in the family Geomyidae. Description There are about fifty-nine members of the family Heteromyidae divided among six genera. They are all small rodents, the largest being the giant kangaroo rat (''Dipodomys ingens'') with a body length of and a tail a little longer than this. In many species the tail is tufted and is mainly used for balance. Other adaptations include partially fused vertebrae in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chaetodipus Spinatus
The spiny pocket mouse (''Chaetodipus spinatus'') is a species of rodent in the family Heteromyidae and order Rodentia. It is found in Baja California in Mexico and in Arizona, California and Nevada. Description The spiny pocket mouse has long hairs and spines on its back that are flexible. These spines differentiates ''C. spinatus'' from pocket mice in other genera.Original publication Their ears are small and round. They have long tails that are 126% of the length of their head and body. Their coat colors vary among islands but are generally brown on the tops of their bodies and tan on their sides. A spiny pocket mouse weighs about . Their body length ranges from . Distribution and habitat Spiny pocket mice are found in Southern |
Perognathinae
Perognathinae is a subfamily of rodents consisting of two genera of pocket mice. Most species live in complex burrows within the deserts and grasslands of western North America, They feed mostly on seeds and other plant parts, which they carry in their fur-lined cheek pouches to their burrows. Description There are about twenty-six members of the subfamily Perognathinae divided among two genera. They are all small rodents. Adaptations include partially fused vertebrae in the neck, short fore limbs and much enlarged bullae (bubble-shaped bones in the skull). The dental formula is 1/1, 0/0, 1/1, 3/3 making twenty teeth in total. The molars have two-lobed cusps. The upper incisors are grooved and the enamel on the molars is quickly worn away by chewing leaving the dentine exposed. The check teeth have roots. Fur-lined cheek pouches are a feature across the family Heteromyidae. They have openings near the mouth and extend backwards along the sides of the neck. The fur on the an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heteromys Salvini
Salvin's spiny pocket mouse (''Heteromys salvini'') is a small to medium-sized rodent in the family Heteromyidae. It was formerly placed in the genus ''Liomys'', which is now recognized to be paraphyletic and has been subsumed into ''Heteromys''. Physical characteristics Like other pocket mice, it has external, fur-lined pouches in its cheeks for carrying seeds and other materials. Although the darkness of the fur can vary quite a bit geographically, it is always grey or grey-brown dorsally with cream-colored underparts, forelegs, and feet. The darker dorsal fur is meshed with dark spiny hairs and lighter, cream-colored hairs. The tail is approximately equal to the body length, bi-color, and nearly hairless (although it may have a short terminal hair cluster). In regions of overlap, ''H. salvini'' can be distinguished from other species by the lack of orange side stripes and a lack of dark forelimbs.Goldman A., Edward. 1911. Revision of the Spiney Pocket Mice Average size *Hea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heteromys Desmarestianus
Desmarest's spiny pocket mouse (''Heteromys desmarestianus'') is a species of rodent in the family Heteromyidae. It is found in Colombia, Costa Rica, El Salvador, Guatemala, Honduras, Mexico, Nicaragua, and Panama Panama ( , ; es, link=no, Panamá ), officially the Republic of Panama ( es, República de Panamá), is a transcontinental country spanning the southern part of North America and the northern part of South America. It is bordered by Co .... References Heteromys Mammals of Colombia Rodents of Central America Mammals described in 1868 Taxonomy articles created by Polbot {{Heteromyidae-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Basal (phylogenetics)
In phylogenetics, basal is the direction of the ''base'' (or root) of a rooted phylogenetic tree or cladogram. The term may be more strictly applied only to nodes adjacent to the root, or more loosely applied to nodes regarded as being close to the root. Note that extant taxa that lie on branches connecting directly to the root are not more closely related to the root than any other extant taxa. While there must always be two or more equally "basal" clades sprouting from the root of every cladogram, those clades may differ widely in taxonomic rank, species diversity, or both. If ''C'' is a basal clade within ''D'' that has the lowest rank of all basal clades within ''D'', ''C'' may be described as ''the'' basal taxon of that rank within ''D''. The concept of a 'key innovation' implies some degree of correlation between evolutionary innovation and diversification. However, such a correlation does not make a given case predicable, so ancestral characters should not be imputed to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Megaannum
A year or annus is the orbital period of a planetary body, for example, the Earth, moving in its orbit around the Sun. Due to the Earth's axial tilt, the course of a year sees the passing of the seasons, marked by change in weather, the hours of daylight, and, consequently, vegetation and soil fertility. In temperate and subpolar regions around the planet, four seasons are generally recognized: spring, summer, autumn and winter. In tropical and subtropical regions, several geographical sectors do not present defined seasons; but in the seasonal tropics, the annual wet and dry seasons are recognized and tracked. A calendar year is an approximation of the number of days of the Earth's orbital period, as counted in a given calendar. The Gregorian calendar, or modern calendar, presents its calendar year to be either a common year of 365 days or a leap year of 366 days, as do the Julian calendars. For the Gregorian calendar, the average length of the calendar year (the mean yea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sister Group
In phylogenetics, a sister group or sister taxon, also called an adelphotaxon, comprises the closest relative(s) of another given unit in an evolutionary tree. Definition The expression is most easily illustrated by a cladogram: Taxon A and taxon B are sister groups to each other. Taxa A and B, together with any other extant or extinct descendants of their most recent common ancestor (MRCA), form a monophyletic group, the clade AB. Clade AB and taxon C are also sister groups. Taxa A, B, and C, together with all other descendants of their MRCA form the clade ABC. The whole clade ABC is itself a subtree of a larger tree which offers yet more sister group relationships, both among the leaves and among larger, more deeply rooted clades. The tree structure shown connects through its root to the rest of the universal tree of life. In cladistic standards, taxa A, B, and C may represent specimens, species, genera, or any other taxonomic units. If A and B are at the same taxo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paraphyletic
In taxonomy, a group is paraphyletic if it consists of the group's last common ancestor and most of its descendants, excluding a few monophyletic subgroups. The group is said to be paraphyletic ''with respect to'' the excluded subgroups. In contrast, a monophyletic group (a clade) includes a common ancestor and ''all'' of its descendants. The terms are commonly used in phylogenetics (a subfield of biology) and in the tree model of historical linguistics. Paraphyletic groups are identified by a combination of synapomorphies and symplesiomorphies. If many subgroups are missing from the named group, it is said to be polyparaphyletic. The term was coined by Willi Hennig to apply to well-known taxa like Reptilia ( reptiles) which, as commonly named and traditionally defined, is paraphyletic with respect to mammals and birds. Reptilia contains the last common ancestor of reptiles and all descendants of that ancestor, including all extant reptiles as well as the extinct synaps ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metaliomys
''Metaliomys'' is an extinct genus of Heteromyidae that existed in the United States The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 states, a federal district, five major unincorporated territori ... during the Late Miocene period. The only species is ''Metaliomys sevierensis''. References Heteromyidae Miocene rodents Fossil taxa described in 2010 Extinct mammals of North America Prehistoric monotypic mammal genera {{Heteromyidae-stub ... [...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, wh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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