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Incamys
''Incamys'' is an extinct genus of chinchillid rodent that lived during the Late Oligocene ( Deseadan) in what is now South America. Fossils of this genus have been found in the Salla Formation of Bolivia and the Agua de la Piedra and Sarmiento Formations of Argentina. Taxonomy ''Incamys'' was first described by Hoffstetter and Lavocat, based on remains found in the Salla Formation of Bolivia, with the proposed type species being ''Incamys bolivianus'', referring to the country it was found in. Later, in 1976, a new species was named, ''I. pretiosus'', which was subsequently found to be a junior synonym of the type species. In 2015, Vucetich and colleagues described a new species of ''Incamys'', ''I. menniorum'', from the Sarmiento Formation of Chubut Province, Argentina. The following cladogram of the Caviomorpha Caviomorpha is the rodent infraorder or parvorder that unites all New World hystricognaths. It is supported by both fossil and molecular evidence. The Caviomorph ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Deseadan
The Deseadan ( es, Deseadense) age is a period of geologic time (29.0–21.0 Ma) within the Oligocene epoch of the Paleogene to the Early Miocene epoch of the Neogene, used more specifically within the SALMA classification of South America. It follows the Tinguirirican and precedes the Colhuehuapian age. Etymology The age is named after the Deseado Formation of the Deseado Massif in eastern Patagonia, Argentina. Formations Fossils Correlations The Deseadan South American land mammal age (SALMA) is equivalent to the Arikareean in the North American land mammal age (NALMA) and the Harrisonian in the 2000 version of the classification. It overlaps with the Hsandagolian The Hsandagolian age is a period of geologic time (33.9 – 23.03 Ma) within the Oligocene epoch of the Paleogene used more specifically with Asian Land Mammal Ages. It follows the Kekeamuan and precedes the Tabenbulakian age. The Ulangochuian ... of Asia and the MP 25 zone of Europe, the Waitaki ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chinchillidae
The family Chinchillidae is in the order Rodentia and consists of the chinchillas, the viscachas, and their fossil relatives. This family is restricted to southern and western South America, mostly living in mountainous regions of the Andes but one species living on plains. They are medium to large-sized rodents, weighing from to , with strong hind legs and large ears and a bushy tail. All species have thick, soft fur, which is considered valuable in some cultures. Characteristics Members of the family Chinchillidae are somewhat rabbit or squirrel-like rodents varying in weight from . They have large eyes, medium-sized ears, soft dense fur and short bushy tails. The forelegs are shorter than the hind legs. The forefeet have four toes while the hind feet have four small-clawed toes in ''Lagidium'' and ''Chinchilla'' but three large-clawed toes in '' Lagostomus'', a digging species. Their dental formula is and their incisors grow continually throughout their lives. Chinchillids a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sarmiento Formation
The Sarmiento Formation (Spanish: ''Formación Sarmiento''), in older literature described as the Casamayor Formation, is a geological formation in Chubut Province, Argentina, in central Patagonia, which spans around 30 million years from the mid-Eocene to the early Miocene. It predominantly consists of pyroclastic deposits, which were deposited in a semi-arid environment. It is divided up into a number of members. The diverse fauna of the Sarmiento Formation, including a variety of birds, crocodilians, turtles and snakes, also includes many mammals such as South American native ungulates (notoungulates, litopterns, astrapotheres) as well as armadillo Armadillos (meaning "little armored ones" in Spanish) are New World placental mammals in the order Cingulata. The Chlamyphoridae and Dasypodidae are the only surviving families in the order, which is part of the superorder Xenarthra, along wi ...s, and caviomorph rodents. Material was copied from this source, which is availabl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Octodontoidea
Caviomorpha is the rodent infraorder or parvorder that unites all New World hystricognaths. It is supported by both fossil and molecular evidence. The Caviomorpha was for a time considered to be a separate order outside the Rodentia, but is now accepted as a genuine part of the rodents. Caviomorphs include the extinct Heptaxodontidae (giant hutias) and extant families of chinchilla rats, hutias, guinea pigs and the capybara, chinchillas and viscachas, tuco-tucos, agoutis, pacas, pacaranas, spiny rats, New World porcupines, coypu and octodonts (Vassallo and Antenucci, 2015). Origin The first known rodent fossils in South America are represented by the three taxa ''Cachiyacuy contamanensis'', ''C. kummeli'', and ''Canaanimys maquiensis'', as well as teeth from ''Eobranisamys'' sp. (Dasyproctidae) and ''Eospina'' sp., the latter two found also in the Santa Rosa fauna from the late Eocene or early Oligocene. By the late Oligocene, all superfamilies and most families of ca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phiomorpha
The rodent parvorder or infraorder Phiomorpha comprises several living and extinct families found wholly or largely in Africa. Along with Anomaluromorpha and perhaps the extinct Zegdoumyidae, it represents one of the few early colonizations of Africa by rodents. During the Oligocene, Africa was not connected to any of the other continents. The predominant theory suggests that rodents first evolved in Laurasia, and expanded outward from there. Although Europe, Asia, and North America were distinct landmasses during much of the Eocene and Oligocene, they experienced intermittent migration events across the shallow sea separating Europe and Asia, via an ice-free Greenland (Europe and North America), or across Beringia (North America and Asia). The southern continents were much more isolated leading to the unique faunas of Australia, South America, and to a lesser degree Africa. Although the hystricognath rodents may have evolved from an early entodacryan ancestor in Asia, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oligocene
The Oligocene ( ) is a geologic epoch of the Paleogene Period and extends from about 33.9 million to 23 million years before the present ( to ). As with other older geologic periods, the rock beds that define the epoch are well identified but the exact dates of the start and end of the epoch are slightly uncertain. The name Oligocene was coined in 1854 by the German paleontologist Heinrich Ernst Beyrich from his studies of marine beds in Belgium and Germany. The name comes from the Ancient Greek (''olígos'', "few") and (''kainós'', "new"), and refers to the sparsity of extant forms of molluscs. The Oligocene is preceded by the Eocene Epoch and is followed by the Miocene Epoch. The Oligocene is the third and final epoch of the Paleogene Period. The Oligocene is often considered an important time of transition, a link between the archaic world of the tropical Eocene and the more modern ecosystems of the Miocene. Major changes during the Oligocene included a global expansion o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Echimyidae
Echimyidae is the family of neotropical spiny rats and their fossil relatives. This is the most species-rich family of hystricognath rodents. It is probably also the most ecologically diverse, with members ranging from fully arboreal to terrestrial to fossorial to semiaquatic habits. They presently exist mainly in South America; three members of the family also range into Central America, and the hutias are found in the Greater Antilles in the Caribbean. Species of the extinct subfamily Heteropsomyinae formerly lived on Cuba, Hispaniola, and Puerto Rico in the Antilles, probably until the arrival of Europeans. Characteristics In general form, most spiny rats resemble rats, although they are more closely related to guinea pigs and chinchillas. Most species have stiff, pointed hairs, or spines, that presumably serve for protection from predators. Many echimyids can break off their tails when attacked. This action may confuse predators long enough for the spiny rat to es ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
