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Adianthidae
Adianthidae is an extinct family of Litopterna, litopterns that existed from the Middle Eocene (Mustersan) to the Early Miocene (Santacrucian). Description These Arboreal locomotion, scansorial, Viviparity, viviparous animals were actively mobile and were Herbivore, herbivores. They were small in size when compared to most litopterns. Most species did not exceed the size of a cat. Although small in size, the adianthids showed dental features that were already specialized even in the Oligocene genera. The molars were equipped with ridges, and the upper molars were provided with crescent-shaped Cusp (anatomy), metacones and Paracone, paracones, with a columnar parastyle and a very reduced or absent mesostyle. The lower fourth premolar was provided with a crested Molar (tooth), talonid, and the lower molars were double crescent-shaped or nearly so. The upper fourth premolar was molar-shaped, and the teeth from the third premolar to the upper third molar had three primary dimples and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Proectocion
''Proectocion'' is an extinct genus of adianthid litoptern. It lived during the Early Eocene, in what is now South America. Description This genus is mainly known from its fossilized teeth, resembling those of '' Didolodus''. However, the structure of the fourth upper molar of ''Proectocion'' was entirely different from those of Didolodontidae ; the paracone and the metacone were well separated, and a small mesostyle was present. The third molard had an hypocone differing from ''Didolodus'', and similar to those of litopterns such as ''Macrauchenia'' and ''Adiantoides''. The pattern of the upper molars crown was different from those of Proterotheriidae, but similar to those of Macraucheniidae, with the hypocone joined anteriorly to the crest of the protocone-metacone. The ventrally directed and truncated paralophids as well as the columnar aspect of the cusps of the lower molars, were characteristics also found in the little-known ''Polymorphis''. The upper molars and premolars h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tricoelodus
''Tricoelodus'' is an extinct genus of adianthid litopterns that lived during the Late Oligocene in what is now Argentina and Bolivia. Fossils of this genus have been found in the Sarmiento Formation of Argentina and the Salla Formation of Bolivia. Naming and classification ''Tricoelodus'' was named by Ameghino in 1897. ''Tricoelodus'' was first assigned to Mesorhinidae by Ameghino in 1897. It was then assigned to Adianthinae by Cifelli & Soria in 1983; and to Adianthidae Adianthidae is an extinct family of litopterns that existed from the Middle Eocene (Mustersan) to the Early Miocene (Santacrucian). Description These scansorial, viviparous animals were actively mobile and were herbivores. They were small in s ... by Cifelli in 1983 and by Carroll in 1988. References {{Taxonbar, from=Q115802019 Litopterns Prehistoric placental genera Oligocene mammals of South America Paleogene Argentina Paleogene Bolivia Fossils of Argentina Fossils of Bolivia Deseada ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Adianthus
''Adianthus'' is an extinct genus of litoptern that lived during the Early Miocene to the Middle Miocene in what is now Argentina and Chile. Description This animal is only known from fragmentary remains, mainly from its teeth, and was probably similar to its relative '' Adiantoides''. It was a small animal with generalist teeth, but it had some unusual characteristics. The crown of its teeth was higher than in ''Adiantoides'', and the lower premolars were more molariform. The second lower incisor and the lower canine had three lingually directed ridges, forming two closed basins. The first three premolars had two ridges, while the fourth premolar was completely molariform. Classification ''Adianthus bucatus'' was first described in 1891 by Florentino Ameghino, based on a single tooth of enigmatic shape, perhaps coming from the so-called "'' Notohippus'' beds". Subsequently, Ameghino described a mandible with teeth as a new species, ''Adianthus patagonicus'' ; however, those ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Proadiantus
''Proadiantus'' (Ameghino, 1897) is an extinct genus of adianthid litoptern. It lived during the Late Oligocene, in what is today South America. It consists of only 1 species, ''Proadiantus excavatus.'' Description This animal is mainly known from fossil remains of its teeth, maxilla and mandible, and its appearance is therefore difficult to restore. It is assumed, from comparison with its better known relatives ''Adianthus'' and '' Adiantoides'', that it was a small and slender litoptern. ''Proadiantus'' differs from ''Adiantoides'' by its significantly larger size, and it may have been as large as a coyote. The molars had rather low upper crowns ; the upper molars had a mesostyle, but no clearly defined metastyle ; the hypoconus was elongated. The talonid of the second lower molar had a complex structure. Classification ''Proadiantus'' was one of the Adianthidae, a family of small sized litopterns with a characteristic dentition. ''Proadiantus'' seems to have been on ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Litopterna
Litopterna (from grc, λῑτή πτέρνα "smooth heel") is an extinct order of fossil hoofed mammals from the Cenozoic era. The order is one of the five great orders of South American ungulates that were endemic to the continent, until the Great American Biotic Interchange brought new ungulate species. Like other endemic South American mammals, their relationship to other mammal groups had long been unclear, but recent genetic and proteomic evidence indicates that their closest living relatives are Perissodactyls (odd-toed ungulates) including horses, rhinoceros, and tapirs, and that litopterns are closely related to notoungulates, another widespread group of South American ungulates. There were two major groups of litopterns: Proterotheriidae and Macraucheniidae. Proterotheriids were medium to large animals that evolved adaptations for fast running, and occupied a variety of niches that elsewhere were filled by animals such as goats and antelopes, mouse deer, and horses. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Macrauchenioidea
Litopterna (from grc, λῑτή πτέρνα "smooth heel") is an extinction, extinct order of fossil hoofed mammals from the Cenozoic era. The order is one of the five great orders of Meridiungulata, South American ungulates that were endemic to the continent, until the Great American Interchange, Great American Biotic Interchange brought new ungulate species. Like other Endemism, endemic South American mammals, their relationship to other mammal groups had long been unclear, but recent genetic and proteomic evidence indicates that their closest living relatives are Odd-toed ungulate, Perissodactyls (odd-toed ungulates) including Equidae, horses, rhinoceros, and Tapir, tapirs, and that litopterns are closely related to Notoungulata, notoungulates, another widespread group of South American ungulates. There were two major groups of litopterns: Proterotheriidae and Macraucheniidae. Proterotheriids were medium to large animals that evolved adaptations for fast running, and occupied ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Litopterns
Litopterna (from grc, λῑτή πτέρνα "smooth heel") is an extinct order of fossil hoofed mammals from the Cenozoic era. The order is one of the five great orders of South American ungulates that were endemic to the continent, until the Great American Biotic Interchange brought new ungulate species. Like other endemic South American mammals, their relationship to other mammal groups had long been unclear, but recent genetic and proteomic evidence indicates that their closest living relatives are Perissodactyls (odd-toed ungulates) including horses, rhinoceros, and tapirs, and that litopterns are closely related to notoungulates, another widespread group of South American ungulates. There were two major groups of litopterns: Proterotheriidae and Macraucheniidae. Proterotheriids were medium to large animals that evolved adaptations for fast running, and occupied a variety of niches that elsewhere were filled by animals such as goats and antelopes, mouse deer, and horses. M ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eocene
The Eocene ( ) Epoch is a geological epoch (geology), epoch that lasted from about 56 to 33.9 million years ago (mya). It is the second epoch of the Paleogene Period (geology), Period in the modern Cenozoic Era (geology), Era. The name ''Eocene'' comes from the Ancient Greek (''ēṓs'', "dawn") and (''kainós'', "new") and refers to the "dawn" of modern ('new') fauna that appeared during the epoch. The Eocene spans the time from the end of the Paleocene Epoch to the beginning of the Oligocene Epoch. The start of the Eocene is marked by a brief period in which the concentration of the carbon isotope Carbon-13, 13C in the atmosphere was exceptionally low in comparison with the more common isotope Carbon-12, 12C. The end is set at a major extinction event called the ''Grande Coupure'' (the "Great Break" in continuity) or the Eocene–Oligocene extinction event, which may be related to the impact of one or more large bolides in Popigai impact structure, Siberia and in what is now ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
South America
South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere at the northern tip of the continent. It can also be described as the southern subregion of a single continent called America. South America is bordered on the west by the Pacific Ocean and on the north and east by the Atlantic Ocean; North America and the Caribbean Sea lie to the northwest. The continent generally includes twelve sovereign states: Argentina, Bolivia, Brazil, Chile, Colombia, Ecuador, Guyana, Paraguay, Peru, Suriname, Uruguay, and Venezuela; two dependent territories: the Falkland Islands and South Georgia and the South Sandwich Islands; and one internal territory: French Guiana. In addition, the ABC islands of the Kingdom of the Netherlands, Ascension Island (dependency of Saint Helena, Ascension and Tristan da Cunha, a British Overseas Territory), Bouvet Island ( dependency of Norway), Pa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
American Museum Novitates
''American Museum Novitates'' is a peer-reviewed academic journal published by the American Museum of Natural History. It was established in 1921. According to the ''Journal Citation Reports'', the journal has a 2013 impact factor The impact factor (IF) or journal impact factor (JIF) of an academic journal is a scientometric index calculated by Clarivate that reflects the yearly mean number of citations of articles published in the last two years in a given journal, as i ... of 1.636. References External links * Publications established in 1921 Open access journals American Museum of Natural History English-language journals Zoology journals Paleontology journals Geology journals Academic journals published by museums 1921 establishments in the United States {{paleontology-journal-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Macraucheniidae
Macraucheniidae is a family in the extinct South American ungulate order Litopterna, that resembled various camelids. The reduced nasal bones of their skulls was originally suggested to have housed a small proboscis, similar to that of the saiga antelope. However, one study suggested that they were openings for large moose-like nostrils. Conversely, prehistoric pictographs by indigenous people seems to depict animals interpreted as macraucheniids with trunks. Their hooves were similar to those of rhinoceroses today, with a simple ankle joint and three digits on each foot. Thus, they may have been capable of rapid directional change when running away from predators, such as large phorusrhacid terror birds, sparassodont metatherians, giant short-faced bears ('' Arctotherium)'' and saber-toothed cats (''Smilodon''). Macraucheniids probably lived in large herds to gain protection against these predators, as well as to facilitate finding mates for reproduction. The family Macrauc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Prehistoric Mammal Families
Prehistory, also known as pre-literary history, is the period of human history between the use of the first stone tools by hominins 3.3 million years ago and the beginning of recorded history with the invention of writing systems. The use of symbols, marks, and images appears very early among humans, but the earliest known writing systems appeared 5000 years ago. It took thousands of years for writing systems to be widely adopted, with writing spreading to almost all cultures by the 19th century. The end of prehistory therefore came at very different times in different places, and the term is less often used in discussing societies where prehistory ended relatively recently. In the early Bronze Age, Sumer in Mesopotamia, the Indus Valley Civilisation, and ancient Egypt were the first civilizations to develop their own scripts and to keep historical records, with their neighbors following. Most other civilizations reached the end of prehistory during the following Iron Age. T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
