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Triconodont
Eutriconodonta is an order of early mammals. Eutriconodonts existed in Asia, Africa, Europe, North and South America during the Jurassic and the Cretaceous periods. The order was named by Kermack ''et al.'' in 1973 as a replacement name for the paraphyletic Triconodonta. Traditionally seen as the classical Mesozoic small mammalian insectivores, discoveries over the years have shown them to be among the best examples of the diversity of mammals in this time period, including a vast variety of bodyplans, ecological niches and locomotion methods. Classification "Triconodonta" had long been used as the name for an order of early mammals which were close relatives of the ancestors of all present-day mammals, characterized by molar teeth with three main cusps on a crown that were arranged in a row. The group originally included only the family Triconodontidae and taxa that were later assigned to the separate family Amphilestidae, but was later expanded to include other taxa such as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Triconodontidae
Triconodontidae is an extinct family of small, carnivorous mammals belonging to the order Eutriconodonta, endemic to what would become Asia, Europe, North America and probably also Africa and South America during the Jurassic through Cretaceous periods at least from 190–70.6 mya. Triconodontids can be distinguished from other eutriconodonts by the shape of their molars, which bore three main cusps of roughly equal size. During occlusion, the upper and lower molars interlocked tightly, producing a self-sharpening cutting edge. Historically, the triconodontids were thought to have a different occlusion pattern than other eutriconodonts, with the middle cusp of the lower molar (cusp a) fitting between the middle cusp (cusp A) and the front cusp (cusp B) of the upper molar, as in the basal mammaliaform ''Morganucodon''. However, a 2020 study on ''Priacodon'' suggests that triconodontids occluded their molars in the same manner as other eutriconodonts (so-called "embrasure occlus ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gobiconodonta
Gobiconodonta is an order (biology), order of extinct mammals known from the Early Jurassic (such as ''Huasteconodon'') to early Late Cretaceous. They are generally held to be part of Eutriconodonta. Biology Like many other non-therian mammals, gobiconodonts retained classical mammalian synapomorphies like epipubic bones (and likely the associated reproductive constrictions), Venomous mammal, venomous spurs and sprawling limbs. However, the forelimb and shoulder anatomy of at least some species like ''Jeholodens'' are similar to those of therian mammals, though the hindlimbs remain more conservative. Gobiconodonts had Evolution of mammalian auditory ossicles, a modern ear anatomy, the main difference from therians being that the ear ossicles were still somewhat connected to the jaw via the Meckel's cartilage. Some information on gobiconodont soft-tissues can be seen in ''Spinolestes'', which was very well preserved, showing evidence of fur and internal organs. ''Spinolestes'' sh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Volaticotherini
Volaticotherini is a clade of eutriconodont mammals from the Mesozoic. In addition to the type genus '' Volaticotherium'', it includes the genera '' Argentoconodon'', '' Ichthyoconodon'', and potentially '' Triconolestes''. Since most remains are primarily teeth, they are foremostly diagnosticated by their highly distinctive molars. However, the remains of one species, '' Volaticotherium antiquum'', show that at least some members of this clade were capable of gliding. and '' Argentoconodon'' shares similar post-cranial features that also indicate aerial locomotion. As such, this clade contains some of the oldest known aerial mammals, alongside the various gliding haramiyidans. Definition Volaticotherini is phylogenetically defined as the clade derived from the most recent common ancestor of ''Argentoconodon'', ''Ichthyoconodon,'' and ''Volaticotherium''. History '' Ichthyoconodon'' was the first described member of this group, back in 1995, previously usually ranked among ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Volaticotherium
''Volaticotherium antiquum'' (meaning "ancient gliding beast") is an extinct, gliding, insectivorous mammal that lived in Asia during the Jurassic period, around 164 mya. It is the only member of the genus ''Volaticotherium''. The discovery of ''Volaticotherium'' provided the earliest-known record of a gliding mammal (70 million years older than the next oldest example), until the discovery of the contemporary haramiyidans '' Maiopatagium'', '' Vilevolodon'' and '' Xianshou'', and provided further evidence of mammalian diversity during the Mesozoic Era. The closely related and significantly older '' Argentoconodon'' shows similar post-cranial adaptations for aerial locomotion also seen in ''Volaticotherium''. Discovery The only known fossil of ''Volaticotherium'' was recovered from the Daohugou Beds of Ningcheng County, Inner Mongolia, China. The age of the Daohugou Beds is currently uncertain and the subject of debate, but most studies suggest an age of around 164 plus or mi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jeholodentidae
The family Jeholodentidae is a possible eutriconodont family that was present in China around 125 million years ago during the time of the dinosaurs. There are currently two genera assigned to the family, '' Yanoconodon'' and '' Jeholodens''. However, recent studies have shown it to be paraphyletic in relation to Triconodontidae Triconodontidae is an extinct family of small, carnivorous mammals belonging to the order Eutriconodonta, endemic to what would become Asia, Europe, North America and probably also Africa and South America during the Jurassic through Cretaceous p ..., with '' Yanoconodon'' being closer to them than to '' Jeholodens''. Taxonomy * Family †Jeholodentidae Luo et al. 2007Mikko's Phylogeny ArchivPaleofile.com (net, info) . ** Genus †'' Yanoconodon'' Luo, Chen, Li & Chen 2007 *** Species †'' Yanoconodon allini'' Luo, Chen, Li & Chen 2007 ** Genus †'' Jeholodens'' Ji, Luo & Ji 1999 *** Species †'' Jeholodens jenkinsi'' Ji, Luo & Ji 1999 Re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sinoconodon
''Sinoconodon'' is an extinct genus of mammaliamorphs that appears in the fossil record of the Lufeng Formation of China in the Sinemurian stage of the Early Jurassic period, about 193 million years ago. While sharing many plesiomorphic traits with other non- mammaliaform cynodonts, it possessed a special, secondarily evolved jaw joint between the dentary and the squamosal bones, which in more derived taxa would replace the primitive tetrapod one between the articular and quadrate bones. The presence of a dentary-squamosal joint is a trait historically used to define mammals. Description This animal had skull of which suggest a presacral body length of and weight about due to the similar parameters to the European hedgehog. ''Sinoconodon'' closely resembled early mammaliaforms like '' Morganucodon'', but it is regarded as more basal, differing substantially from ''Morganucodon'' in its dentition and growth habits. Like most other non-mammalian tetrapods, such as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Morganucodon
''Morganucodon'' ("Glamorgan tooth") is an early mammaliaform genus that lived from the Late Triassic to the Middle Jurassic. It first appeared about 205 million years ago. Unlike many other early mammaliaforms, ''Morganucodon'' is well represented by abundant and well preserved (though in the vast majority of cases disarticulated) material. Most of this comes from Glamorgan in Wales (''Morganucodon watsoni''), but fossils have also been found in Yunnan Province in China (''Morganucodon oehleri'') and various parts of Europe and North America. Some closely related animals (''Megazostrodon'') are known from exquisite fossils from South Africa. The name comes from a Latinization of ''Morganuc'', the name for South Glamorgan in the Domesday Book, the county of Wales where it was discovered by Walter Georg Kühne,Walter G. Kühne, "On a Triconodont tooth of a new pattern from a Fissure-filling in South Glamorgan", ''Proceedings of the Zoological Society of London'', volume 119 (1949 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Triconodon Owen
''Triconodon'' ("three coned tooth") is a genus of extinct mammal from the Early Cretaceous of England and France with two known species: ''T. mordax'' and ''T. averianovi''. First described in 1859 by Richard Owen,R. Owen. 1859. Palaeontology. '' Encyclopedia Britannica, 8th ed.'' 17:91-176 . Wagner/P. Wagner it is the type genus for the order Triconodonta, a group of mammals characterised by their three-cusped (triconodont) molar teeth. Since then, this "simplistic" type of dentition has been understood to be either ancestral for mammals or else to have evolved multiple times, rendering "triconodonts" a paraphyletic or polyphyletic assemblage respectively, but several lineages of "triconodont" mammals do form a natural, monophyletic group, known as Eutriconodonta, of which ''Triconodon'' is indeed part of. ''Triconodon'', therefore, is significant in the understanding of the evolution of mammals by originating the understanding of the "triconodont" grade and eutriconodon ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Liaoconodon
''Liaoconodon'' is an extinct genus of early mammal from the early Cretaceous (early Aptian stage, approximately 120 Ma). It is a eutriconodont which lived in what is now the Jianchang of Liaoning Province, eastern China. It is known from the holotype IVPP V 16051, which consists of nearly complete skeleton and skull. It was found in the Jiufotang Formation (Jehol Biota) near Xiaotaizi, Lamadong. It was first named by Jin Meng, Yuanqing Wang and Chuankui Li in 2011 and the type species is ''Liaoconodon hui''. Studies on its anatomy show that it was a semi-aquatic mammal, having a long body and paddle-like limbs. Phylogeny Cladogram after Thomas Martin Thomas or Tom Martin may refer to: Born 16th century *Thomas Martin (politician, died 1583) (1530–1583), MP for Dorchester * Thomas Martin (lawyer) (1521–1593), MP for Ludgershall, Saltash and Hindon Born 17th century *Thomas Martin of Pa ... et al. 2015Thomas Martin, Jesús Marugán-Lobón, Romain Vu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dyskritodon
''Dyskritodon'' ("tooth of unknown origin", from Greek δυσκρίτος, "''dyskritos''"Sigogneau-Russell, D. (1995) Two possibly aquatic triconodont mammals from the Early Cretaceous of Morocco. Acta Palaeontologica Polonica. 40(2), p.149-162.) is a genus of extinct mammal from the Early Cretaceous of Morocco, and possibly the Early Jurassic of India. Of uncertain affinities, it is tentatively described as a eutriconodont. Description The type species, ''D. amazighi'', is known from the Ksar Metlili Formation in the Atlas Mountains, dating to the Berriasian. It is known from several molars, about 1.85 mm long. These teeth are noted for being rather high and narrow crowned, bearing three main cusps that decrease in height posteriorly, as well as two minuscule mesial cusps. ''D. indicus'' is known from a single lower molar tooth from the Kota Formation, dating to the Hettangian-Pliensbachian. It is very similar to ''D. amazighi'', differing in being smaller (1.24 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amphidontidae
The Amphidontidae are a family of extinct mammals from the Early Cretaceous, belonging to the triconodonts. It contains most of the species previously belonged to Amphilestidae. Phylogeny Cladogram A cladogram (from Greek ''clados'' "branch" and ''gramma'' "character") is a diagram used in cladistics to show relations among organisms. A cladogram is not, however, an evolutionary tree because it does not show how ancestors are related to ... after Marisol Montellano, James A. Hopson, James M. Clark (2008) and Gao ''et al.'' (2010). Taxonomy Based on the works by Mikko HaaramoMikko's Phylogeny Archiv and the Palaeofile website.Paleofile.com (net, info) . *Family †Amphidontidae Simpson 1925 **Genus †'' Acinacodus'' Lopatin, Maschenko & Averianov 2010 ***Species †'' Acinacodus tagaricus'' Lopatin, Maschenko & Averianov 2010 **Genus †'' Aploconodon'' Simpson 1925 ***Species †'' Aploconodon comoensis'' Simpson 1925 **Genus †'' Comodon'' Kretzoi & Kretzoi 2000 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cretaceous
The Cretaceous ( ) is a geological period that lasted from about 145 to 66 million years ago (Mya). It is the third and final period of the Mesozoic Era, as well as the longest. At around 79 million years, it is the longest geological period of the entire Phanerozoic. The name is derived from the Latin ''creta'', "chalk", which is abundant in the latter half of the period. It is usually abbreviated K, for its German translation ''Kreide''. The Cretaceous was a period with a relatively warm climate, resulting in high eustatic sea levels that created numerous shallow inland seas. These oceans and seas were populated with now- extinct marine reptiles, ammonites, and rudists, while dinosaurs continued to dominate on land. The world was ice free, and forests extended to the poles. During this time, new groups of mammals and birds appeared. During the Early Cretaceous, flowering plants appeared and began to rapidly diversify, becoming the dominant group of plants across the Ear ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
