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Gondwanatheria
Gondwanatheria is an extinct group of mammaliaforms that lived in parts of Gondwana, including Madagascar, India, South America, Africa and Antarctica during the Upper Cretaceous through the Paleogene (and possibly much earlier, if '' Allostaffia'' is a member of this group). Until recently, they were known only from isolated teeth, a few lower jaws, two partial skulls and one complete cranium. They are generally considered to be closely related to the multituberculates and likely the euharamiyidians, well known from the Northern Hemisphere, with which they form the clade Allotheria. Classification For several decades the affinities of the group were not clear, being first interpreted as early xenarthrans, or "toothless" mammals similar to the modern anteater. A variety of studies have placed them as allotheres related to multituberculates, possibly even true multituberculates, closer to cimolodonts than "plagiaulacidans" are. However, a more recent study recovered them as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ferugliotheriidae
Ferugliotheriidae is one of three known family (biology), families in the order (biology), order Gondwanatheria, an enigmatic group of extinction, extinct mammals. Gondwanatheres have been classified as a group of uncertain affinities or as members of Multituberculata, a major extinct mammalian order. The best-known representative of Ferugliotheriidae is the genus ''Ferugliotherium'' from the Late Cretaceous epoch in Argentina. A second genus, ''Trapalcotherium'', is known from a single tooth, a first lower wikt:molariform, molariform (Molar (tooth), molar-like tooth), from a different Late Cretaceous Argentinean locality. Another genus known from a single tooth (in this case, a fourth lower premolar), ''Argentodites'', was first described as an unrelated multituberculate, but later identified as possibly related to ''Ferugliotherium''. Finally, a single tooth from the Paleogene of Peru, LACM 149371, perhaps a last upper molariform, and a recent specimen from Mexico, may represent ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ferugliotherium
''Ferugliotherium'' is a genus of fossil mammals in the family Ferugliotheriidae from the Campanian and/or Maastrichtian period (Late Cretaceous; around 70 million years ago) of Argentina. It contains a single species, ''Ferugliotherium windhauseni'', which was first described in 1986. Although originally interpreted on the basis of a single brachydont (low- crowned) molar as a member of Multituberculata, an extinct group of small, rodent-like mammals, it was recognized as related to the hypsodont (high-crowned) Sudamericidae following the discovery of additional material in the early 1990s. After a jaw of the sudamericid ''Sudamerica'' was described in 1999, these animals (collectively known as Gondwanatheria) were no longer considered to be multituberculates and a few fossils that were previously considered to be ''Ferugliotherium'' were assigned to unspecified multituberculates instead. Since 2005, a relationship between gondwanatheres and multituberculates has again received s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Multituberculates
Multituberculata (commonly known as multituberculates, named for the multiple tubercles of their teeth) is an extinct order of rodent-like mammals with a fossil record spanning over 130 million years. They first appeared in the Middle Jurassic, and reached a peak diversity during the Late Cretaceous and Paleocene. They eventually declined from the mid Paleocene onwards, disappearing from the known fossil record in the late Eocene. They are the most diverse order of Mesozoic mammals with more than 200 species known, ranging from mouse-sized to beaver-sized. These species occupied a diversity of ecological niches, ranging from burrow-dwelling to squirrel-like arborealism to jerboa-like hoppers. Multituberculates are usually placed as crown mammals outside either of the two main groups of living mammals—Theria, including placentals and marsupials, and MonotremataAgustí-Antón 2002, pp 3-4—but usually as closer to Theria than to monotremes. They are considered to be clo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Groeberiidae
Groeberiidae is a family of strange non-placental mammals from the Eocene and Oligocene epochs of Patagonia, Argentina and Chile, South America. Originally classified as paucituberculate marsupials, they were suggested to be late representatives of the allothere clade Gondwanatheria. However, the relationship of the type genus, '' Groeberia'', to Gondwanatheria has been firmly rejected by other scholars. History The type species, '' Groeberia minoprioi'', was first described by Bryan Patterson in 1952. This type specimen, MMP 738, is composed of a mandibular symphisis, incisors and four broken molars. A second species within the genus, '' Groeberia pattersoni'', was described by G. G. Simpson in 1970, and is known from at least two specimens.Goin, F.J., Abello M.A. & Chornogubsky L. 2010Middle Tertiary marsupials from Central Patagonia (Early Oligocene of Gran Barranca): Understanding South America’s ''Grande Coupure'' En: Madden R.H., Carlini A.A., Vucetich M.G. & Kay R.F ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lavanify
''Lavanify'' is a mammalian genus from the late Cretaceous (probably Maastrichtian, about 71 to 66 million years ago) of Madagascar. The only species, ''L. miolaka'', is known from two isolated teeth, one of which is damaged. The teeth were collected in 1995–1996 and described in 1997. The animal is classified as a member of Gondwanatheria, an enigmatic extinct group with unclear phylogenetic relationships, and within Gondwanatheria as a member of the family Sudamericidae. ''Lavanify'' is most closely related to the Indian ''Bharattherium''; the South American '' Sudamerica'' and '' Gondwanatherium'' are more distantly related. Gondwanatheres probably ate hard plant material. ''Lavanify'' had high- crowned, curved teeth. One of the two teeth is 11.2 mm high and shows a deep furrow and, is centered laterally in the crown, a V-shaped area that consists of dentine. The other, damaged, tooth is 9.8 mm high and has at least one deep cavity (infundibulum). Characters s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Argentodites
''Argentodites'' is a possible multituberculate mammal from the Cretaceous of Argentina. The single species, ''Argentodites coloniensis'', is known from a single blade-like fourth lower premolar (p4) from the La Colonia Formation, which is mostly or entirely Maastrichtian (latest Cretaceous) in age. The p4 is 4.15 mm long and bears eight cusps on its upper margin and long associated ridges on both sides. The enamel consists of prisms that are completely or partly surrounded by a sheath and that are on average 6.57 μm apart. Zofia Kielan-Jaworowska, who described and named the fossil in 2007, regarded it as a multituberculate, perhaps a cimolodontan—and thus, a member of a mostly Laurasian (northern) group and an immigrant to Argentina from North America—on the basis of the shape of the tooth and features of its enamel. In 2009, however, two teams argued that ''Argentodites'' may in fact be close to or identical with ''Ferugliotherium'', a member of the small Go ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Euharamiyida
Euharamiyida also known as Eleutherodontida, is clade of early mammals or mammal-like cynodonts from the Middle Jurassic to Early Cretaceous of Eurasia and possibly North America. The group is sometimes considered a sister group to Multituberculata, or part of an earlier divergence within the synapsid line. It is disputed whether or not they are related to the Haramiyids from the Late Triassic, such as ''Haramiyavia''. The morphology of their teeth indicates that they were herbivorous or omnivorous. Some members of the group are known to be arboreal, including gliding forms similar to modern flying squirrels or colugos. Evolution The position of euharamyidans is contested. They are either considered crown group mammals as members of Allotheria, related to multituberculates, or they are considered to stem-group mammals within the Mammaliaformes. The position is often dependent on the relationships of euharamiyids to the Late Triassic haramiyids such as ''Haramiyavia'' and ''Thom ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trapalcotherium
''Trapalcotherium'' is a fossil mammal from the Cretaceous of Argentina in the family Ferugliotheriidae. The single species, ''T. matuastensis'', is known from one tooth, a first lower molar. It is from the Allen Formation, which is probably Maastrichtian in age, and was first described in 2009. The tooth bears two rows of cusps, one at the inner (lingual) side and the other at the outer (labial) side, which are connected by transverse ridges separated by deep valleys. This pattern is reminiscent of ''Ferugliotherium'', a gondwanathere mammal from similarly aged deposits in Argentina, and ''Trapalcotherium'' is therefore recognized as a member of the same family Ferugliotheriidae. Ferugliotheriidae is one of two families of gondwanatheres, an enigmatic group without close relationships to any living mammals. Discovery and context The only known fossil of ''Trapalcotherium'' was found at Cerro Tortuga in Río Negro Province, southern Argentina. This locality is in the Allen For ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sudamerica
''Sudamerica'', literally "South America" in Spanish, is a genus of mammal from the extinct suborder Gondwanatheria that lived in Patagonia, Argentina (Salamanca Formation) and Antarctica (La Meseta Formation) from the Middle Paleocene (Peligran), just after the end of the " Age of Dinosaurs", to the Early Eocene (Casamayoran).''Sudamerica'' at Fossilworks.org Etymology The genus and species were named by Scillato-Yané and R. Pascual in 1984. The genus is also known by the synonym ''Sudamericana'' and the species epithet ''ameghinoi'' refers to notable Argentinian paleontologist |
Magallanodon
''Magallanodon'' is a genus of mammals from the extinct group Gondwanatheria. It contains a single species, ''Magallanodon baikashkenke''. The species is the first Mesozoic mammal known from Chile, and is Late Cretaceous in age. It is known from individual teeth found in a quarry in the Río de Las Chinas Valley and La Anita Farm located in the Magallanes Basin in Patagonia. The fossils come from the Dorotea Formation and Chorrillo Formation, which is Late Campanian to Early Maastrichtian in age. Etymology The name ''Magallanodon'' comes from the Magallanes Region The Magallanes Region (), officially the Magallanes y la Antártica Chilena Region ( es, Región de Magallanes y de la Antártica Chilena), is one of Chile's 16 first order administrative divisions. It is the southernmost, largest, and second lea ... in southern Chile and ''odontos'', Greek for tooth. The species name, ''M. baikashkenke'' is taken from the Tehuelchian words ''bai'' (grandfather) and ''kashkenke' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Allotheria
Allotheria (meaning "other beasts", from the Greek , '–other and , '–wild animal) is an extinct branch of successful Mesozoic mammals. The most important characteristic was the presence of lower molariform teeth equipped with two longitudinal rows of cusps. Allotheria includes Multituberculata, Gondwanatheria (which may be part of Multituberculata, as the sister group to Cimolodonta), and probably Haramiyida, although some studies show them to be more basal mammaliaforms rather than true mammals, therefore differing from true allotheres significantly. Allotheres also had a narrow pelvis, indicating that they gave birth to tiny helpless young like marsupials or laid eggs and gave milk to feed their young like monotremes do. This is a feature of all non-placental mammals. Interpretations When he first identified Allotheria in 1880, Othniel Marsh regarded this group as an order within Marsupialia. However, in 1997 McKenna and Bell classified Allotheria as an infraclass I ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gondwana
Gondwana () was a large landmass, often referred to as a supercontinent, that formed during the late Neoproterozoic (about 550 million years ago) and began to break up during the Jurassic period (about 180 million years ago). The final stages of break-up, involving the separation of Antarctica from South America (forming the Drake Passage) and Australia, occurred during the Paleogene. Gondwana was not considered a supercontinent by the earliest definition, since the landmasses of Baltica, Laurentia, and Siberia were separated from it. To differentiate it from the Indian region of the same name (see ), it is also commonly called Gondwanaland. Gondwana was formed by the accretion of several cratons. Eventually, Gondwana became the largest piece of continental crust of the Palaeozoic Era, covering an area of about , about one-fifth of the Earth's surface. During the Carboniferous Period, it merged with Laurasia to form a larger supercontinent called Pangaea. Gondwana (and Pan ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
