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Sparnotheriodontids
Sparnotheriodontidae is an enigmatic extinct family of litopterns known primarily from teeth. Sparnotheriodontids are one of two South American native ungulate clades known to have reached Antarctica, the other being astrapotheres. Description Sparnotheriodontids ranged in size from the mid-sized ''Phoradiadus'' to the large ''Sparnotheriodon''. ''Sparnotheriodon'' and one species of ''Notiolofos'', ''N. arquinotiensis'', have been estimated to have had masses of roughly . Another species of ''Notiolofos'', ''N. regueroi'', was smaller, with a body mass estimated to have been between 25 and 58 kg. Classification The phylogenetic position of Sparnotheriodontidae is uncertain. Most researchers consider them to belong to Litopterna. In contrast, Cifelli and Bergqvist have argued that sparnotheriodontids are condylarths. Their methodology, based on attempting to associate isolated teeth and isolated postcranial bones based on size and relative abundance, has been criticized. Phyl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sparnotheriodontids
Sparnotheriodontidae is an enigmatic extinct family of litopterns known primarily from teeth. Sparnotheriodontids are one of two South American native ungulate clades known to have reached Antarctica, the other being astrapotheres. Description Sparnotheriodontids ranged in size from the mid-sized ''Phoradiadus'' to the large ''Sparnotheriodon''. ''Sparnotheriodon'' and one species of ''Notiolofos'', ''N. arquinotiensis'', have been estimated to have had masses of roughly . Another species of ''Notiolofos'', ''N. regueroi'', was smaller, with a body mass estimated to have been between 25 and 58 kg. Classification The phylogenetic position of Sparnotheriodontidae is uncertain. Most researchers consider them to belong to Litopterna. In contrast, Cifelli and Bergqvist have argued that sparnotheriodontids are condylarths. Their methodology, based on attempting to associate isolated teeth and isolated postcranial bones based on size and relative abundance, has been criticized. Phyl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sparnotheriodon
''Sparnotheriodon'' is an extinct genus of sparnotheriodontid litoptern that lived during the Middle Eocene of what is now Argentina, leaving fossils in the Sarmiento Formation. Description ''Sparnotheriodon'' was a medium-sized litoptern. ''Sparnotheriodon'', ''Victorlemoinea'', and one species of ''Notiolofos'', ''N. arquinotiensis'', have been estimated to have had masses of roughly , whereas another species of ''Notiolofos'', ''N. regueroi'', was smaller, with a body mass estimated between 25 and 58 kg, making them one of the largest litopterns of the Paleogene. Litopterns reached such sizes again in the Miocene. Taxonomy ''Sparnotheriodon'' was first named by Miguel Fernando Soria in 1980 on the basis of a mandible and teeth from the Sarmiento Formation of Argentina, with the type species being ''Sparnotheriodon epsilonoides''. In 1983, Richard Cifelli tentatively synonymized ''Sparnotheriodon'' with ''Victorlemoinea ''Victorlemoinea'' is an extinct litoptern genus of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Notiolofos
''Notiolofos'' is an extinct genus of sparnotheriodontid ungulate from the order Litopterna. The animal lived during the Eocene, in modern-day Antarctica. The genus contains two species, ''N. arquinotiensis'', the type species, and ''N. regueroi''. Description ''Notiolofos'' was originally named in 2006 by Bond ''et al.'', as '' Notolophus arquinotiensis'', on the basis of a few fossil teeth. However, after the genus was named, it became clear that the name ''Notolophus'' was already in use by a genus of moths, and the genus name was subsequently changed to ''Notiolofos'' by Bond ''et al.'' in 2009. The second species in the genus, ''Notiolofos regueroi'', was named in 2017 by Gelfo, Lopéz & Santillana, based on a single fossil molar. Fossils of ''N. arquinotiensis'' have been found in multiple layers of the La Meseta Formation of Seymour Island, Antarctica, and are dated from 55 to 34 million years ago. However, ''N. regueroi'' is only known from the Cucullaea I layer from ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Victorlemoinea
''Victorlemoinea'' is an extinct litoptern genus of the family Sparnotheriodontidae, that lived from the Early to Middle Eocene. Fossils of ''Victorlemoinea'' have been found in the Las Flores, Sarmiento and Koluel Kaike Formations of Argentina, the Itaboraí Formation of Brazil and La Meseta Formation, Antarctica.''Victorlemoinea'' at .org Description ''Victorlemoinea'' was a medium-sized litoptern. '' Sparnotheriodon'', ''Victorlemoinea'', and one species of '' |
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] |
Protheosodon
''Protheosodon'' is an extinct genus of proterotheriid litoptern. It lived from the Late Oligocene to the Early Miocene in what is now Argentina and Colombia. Description It was a medium-sized animal, smaller than the extant vicuña. The lower incisors, unlike those of more derived proterotheriids such as ''Diadiaphorus'', were relatively small and unspecialized. The lower dentition was complete and there was no trace of diastema. The upper teeth were similar to those of ''Anisolambda'' and ''Polymorphis''. The mandible had a very high vertical branch. Its leg bones, firstly attributed to a notoungulate, are incompletely known. Classification ''Protheosodon coniferus'' was first described in 1897 by Florentino Ameghino, based on fossils found in Deseadan deposits from Chubut Province, Argentina. Other fossils attributed to the genus have been found in slightly older deposits in Colombia. ''Protheosodon'' was initially thought to be a member of Macraucheniidae, mainly ba ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paleogene Mammals Of South America
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 ... [...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] |
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] |
Condylarths
Condylarthra is an informal group – previously considered an order – of extinct placental mammals, known primarily from the Paleocene and Eocene epochs. They are considered early, primitive ungulates. It is now largely considered to be a wastebasket taxon, having served as a dumping ground for classifying ungulates which had not been clearly established as part of either Perissodactyla or Cetartiodactyla, being composed thus of several unrelated lineages. Taxonomic history Condylarthra always was a problematic group. When Condylarthra was first described by , Phenacodontidae was the type and only family therein. , however, raised Condylarthra to an order and included a wide range of diverse placentals with generalized dentitions and postcranial skeletons. More recent researchers (i.e. post-WW2) have been more restrictive; either including only a limited number of taxa, or proposing that the term should be abandoned altogether. Due to their primitive characteristics condylar ... [...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] |
Ypresian
In the geologic timescale the Ypresian is the oldest age (geology), age or lowest stage (stratigraphy), stratigraphic stage of the Eocene. It spans the time between , is preceded by the Thanetian Age (part of the Paleocene) and is followed by the Eocene Lutetian Age. The Ypresian is consistent with the lower Eocene. Events The Ypresian Age begins during the throes of the Paleocene–Eocene Thermal Maximum (PETM). The Fur Formation in Denmark, the Messel shales in Germany, the Oise amber of France and Cambay amber of India are of this age. The Eocene Okanagan Highlands are an uplands subtropical to temperate series of lakes from the Ypresian. Stratigraphic definition The Ypresian Stage was introduced in scientific literature by Belgium, Belgian geologist André Hubert Dumont in 1850. The Ypresian is named after the Flanders, Flemish city of Ypres in Belgium (spelled ''Ieper'' in Dutch). The definitions of the original stage were totally different from the modern ones. The Ypresi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
_(14577238310).jpg "Click for more on -> Protheosodon")
