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Requisia
''Requisia'' is an extinct genus of litoptern from the Early Paleocene of Argentina. Its fossilized remains were found in the Salamanca Formation in the Chubut Province. It is a monotypic genus, its only known species being ''Requisia vidmari''. Description It had a dental morphology quite similar to ''Notonychops'', but with more basal characters. The cuspid morphology, the type of wear and the crescent-shaped characters of the third upper molar indicates that ''Requisia vidmari'' had strong signs of solenodont characters, and is therefore considered as one of the basal representatives of the order Litopterna. ''Requisia'' is more basal than ''Notonychops'', but their morphological similarities could justify to include them in the same family, Notonychopidae, potentially alongside '' Wainka''. It is supposed that the adaptive radiation of South American ungulate Ungulates ( ) are members of the diverse clade Ungulata which primarily consists of large mammals with hooves. T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Salamanca Formation
The Salamanca Formation is a geologic formation in the Golfo San Jorge Basin of central Patagonia that yields well-preserved, well-dated fossils from the early Paleocene. Studies of these fossils are providing new data on plant and animal diversity following the Cretaceous–Paleogene extinction event, end-Cretaceous extinction event. Material was copied from this source, which is available under a creativecommons:by/4.0/, Creative Commons Attribution 4.0 International License The Salamanca Formation crops out in the San Jorge Basin in southern Chubut and northern Santa Cruz provinces, Argentina, overlying the Cretaceous Chubut Group and is part of the Paleocene and Eocene Río Chico Group. The formation yields abundant plant remains as well as fossils of Invertebrate, invertebrates, marine macrofaunas, Reptile, reptiles, and Mammal, mammals. The formation consists primarily of estuarine to shallow marine deposits. Palynological analysis of the Salamanca Formation shows low flora ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wainka
''Wainka'' is an extinct genus of South American mammal, belonging to the order Litopterna. It lived during the Middle Paleocene. Description This animal is only known for a few teeth. The upper molars were almost triangular in shape, elongated, and possessed a rather massive paracone and metacone, more developed than other contemporary South American ungulates such as ''Anisolambda'' ; the upper molars were devoid of mesostyle. With some doubts, ''Wainka'' has also been attributed a lower molar with well-marked ridges. Classification ''Wainka tshotshe'' was first described in 1935 by George Gaylord Simpson, based on an upper and lower molar, the latter of dubious attribution, from the Middle Paleocene of Cerro Redondo, Argentina. This animal has been attributed to various families of South American ungulates, such as the Notonychopidae and Proterotheriidae. Regardless, ''Wainka'' was a basal form and it is very likely that it was an early litoptern. Its real affinities are s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Litoptern
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 hors ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Notonychops
''Notonychops'' is an extinct genus of mammal, belonging to the order Litopterna, that lived during the Middle to Late Paleocene in what is today South America. Description This genus is only known from a fragmentary mandible and maxilla, and it is therefore difficult to hypothesize on its general appearance. ''Notonychops'' had a specialized set of teeth, with selenodont lower molars and premolars with a strong parastyle and a metastyle with paracone and protocone, and the first premolar was absent. The molars had a strong parastyle, and were similar to those of primitive tillodonts, such as '' Esthonyx'', and of little known litopterns such as '' Indalecia''. Classification ''Notonychops powelli'' was first described by Miguel Soria in 1989, based on fossilized remains found in the lower member of the Rio Loro Formation in Argentina. According to Soria, ''Notonychops'' was a representative of a radiation of primitive South American ungulates, Notopterna, distinct from b ... [...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] |
Paleocene
The Paleocene, ( ) or Palaeocene, is a geological epoch (geology), epoch that lasted from about 66 to 56 mya (unit), million years ago (mya). It is the first epoch of the Paleogene Period (geology), Period in the modern Cenozoic Era (geology), Era. The name is a combination of the Ancient Greek ''palaiós'' meaning "old" and the Eocene Epoch (which succeeds the Paleocene), translating to "the old part of the Eocene". The epoch is bracketed by two major events in Earth's history. The K–Pg extinction event, brought on by Chicxulub impact, an asteroid impact and possibly volcanism, marked the beginning of the Paleocene and killed off 75% of living species, most famously the non-avian dinosaurs. The end of the epoch was marked by the Paleocene–Eocene Thermal Maximum (PETM), which was a major climatic event wherein about 2,500–4,500 gigatons of carbon were released into the atmosphere and ocean systems, causing a spike in global temperatures and ocean acidification. In the Pal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Golfo San Jorge Basin
The Golfo San Jorge Basin ( es, Cuenca del Golfo San Jorge) is a hydrocarbon-rich sedimentary basin located in eastern Patagonia, Argentina. The basin covers the entire San Jorge Gulf and an inland area west of it, having one half located in Santa Cruz Province, Argentina, Santa Cruz Province and the other in Chubut Province. The northern boundary of the basin is the North Patagonian Massif while the Deseado Massif forms the southern boundary of the basin. The basin has largely developed under condition of extensional tectonics, including rifting. The basin is of paleontological significance as it hosts six out of 22 defining formations for the South American land mammal age, SALMA classification, the geochronology for the Cenozoic used in South America. At the center of the basin accumulated sediments reach more than of thickness. Oil was first discovered in 1907 and over the years it has become the second most productive hydrocarbon basin in Argentina after Neuquén Basin. St ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Prehistoric Placental Genera
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] |
Fossil Taxa Described In 1997
A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved in amber, hair, petrified wood and DNA remnants. The totality of fossils is known as the ''fossil record''. Paleontology is the study of fossils: their age, method of formation, and evolutionary significance. Specimens are usually considered to be fossils if they are over 10,000 years old. The oldest fossils are around 3.48 billion years old to 4.1 billion years old. Early edition, published online before print. The observation in the 19th century that certain fossils were associated with certain rock strata led to the recognition of a geological timescale and the relative ages of different fossils. The development of radiometric dating techniques in the early 20th century allowed scientists to quantitatively measure the abso ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fossils Of Argentina
A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved in amber, hair, petrified wood and DNA remnants. The totality of fossils is known as the ''fossil record''. Paleontology is the study of fossils: their age, method of formation, and evolutionary significance. Specimens are usually considered to be fossils if they are over 10,000 years old. The oldest fossils are around 3.48 billion years old to 4.1 billion years old. Early edition, published online before print. The observation in the 19th century that certain fossils were associated with certain rock strata led to the recognition of a geological timescale and the relative ages of different fossils. The development of radiometric dating techniques in the early 20th century allowed scientists to quantitatively measure the absolute ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paleogene Argentina
The Paleogene ( ; also spelled Palaeogene or Palæogene; informally Lower Tertiary or Early Tertiary) is a geologic period and system that spans 43 million years from the end of the Cretaceous Period million years ago ( Mya) to the beginning of the Neogene Period Mya. It is the beginning of the Cenozoic Era of the present Phanerozoic Eon. The earlier term Tertiary Period was used to define the span of time now covered by the Paleogene Period and subsequent Neogene Period; despite no longer being recognised as a formal stratigraphic term, 'Tertiary' is still widely found in earth science literature and remains in informal use. Paleogene is often abbreviated "Pg" (but the United States Geological Survey uses the abbreviation PE for the Paleogene on the Survey's geologic maps). During the Paleogene, mammals diversified from relatively small, simple forms into a large group of diverse animals in the wake of the Cretaceous–Paleogene extinction event that ended the preceding Cr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paleocene Mammals Of South America
The Paleocene, ( ) or Palaeocene, is a geological epoch that lasted from about 66 to 56 million years ago (mya). It is the first epoch of the Paleogene Period in the modern Cenozoic Era. The name is a combination of the Ancient Greek ''palaiós'' meaning "old" and the Eocene Epoch (which succeeds the Paleocene), translating to "the old part of the Eocene". The epoch is bracketed by two major events in Earth's history. The K–Pg extinction event, brought on by an asteroid impact and possibly volcanism, marked the beginning of the Paleocene and killed off 75% of living species, most famously the non-avian dinosaurs. The end of the epoch was marked by the Paleocene–Eocene Thermal Maximum (PETM), which was a major climatic event wherein about 2,500–4,500 gigatons of carbon were released into the atmosphere and ocean systems, causing a spike in global temperatures and ocean acidification. In the Paleocene, the continents of the Northern Hemisphere were still connected via som ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
