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Triconodont
Eutriconodonta is an order (biology), order of early mammals. Eutriconodonts existed in Asia, Africa, Europe, North America, 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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gobiconodonta
Gobiconodonta is an 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 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 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'' shows hair similar to that of modern mammals, with compound hair follicles ... [...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 molar (tooth), molars. However, the remains of one species, ''Volaticotherium antiquum'', show that at least some members of this clade were capable of Gliding flight, 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 ... [...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 eutriconodont clad ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dyskritodon
''Dyskritodon'' ("tooth of unknown origin", from Greek language, 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 Molar (tooth), 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 ... [...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 occlusio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Yanoconodon
''Yanoconodon'' is a monotypic genus of extinct early mammal whose representative species ''Yanoconodon allini'' lived during the Mesozoic in what is now China. The holotype fossil of ''Yanoconodon'' was excavated in the Yan Mountains about 300 kilometres from Beijing in the Qiaotou member of the Huajiying Formation (which the original authors considered part of the Yixian Formation) of Hebei Province, China, and is therefore of uncertain age. The Qiaotou Member may correlate with the more well-known Early Cretaceous Yixian Formation, and so probably dates to around 122 Ma ago.Jin, F., Zhang, F.C., Li, Z.H., Zhang, J.Y., Li, C. and Zhou, Z.H. (2008). "On the horizon of ''Protopteryx'' and the early vertebrate fossil assemblages of the Jehol Biota." ''Chinese Science Bulletin'', 53(18): 2820-2827. ''Yanoconodon'' was a eutriconodont, a group composing most taxa once classified as "triconodonts" which lived during the time of the dinosaurs. These were a highly ecologically dive ... [...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] |
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 minus ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mammal
Mammals () are a group of vertebrate animals constituting the class Mammalia (), characterized by the presence of mammary glands which in females produce milk for feeding (nursing) their young, a neocortex (a region of the brain), fur or hair, and three middle ear bones. These characteristics distinguish them from reptiles (including birds) from which they diverged in the Carboniferous, over 300 million years ago. Around 6,400 extant species of mammals have been described divided into 29 orders. The largest orders, in terms of number of species, are the rodents, bats, and Eulipotyphla (hedgehogs, moles, shrews, and others). The next three are the Primates (including humans, apes, monkeys, and others), the Artiodactyla ( cetaceans and even-toed ungulates), and the Carnivora (cats, dogs, seals, and others). In terms of cladistics, which reflects evolutionary history, mammals are the only living members of the Synapsida (synapsids); this clade, together with Saur ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jeholodens
''Jeholodens'' was a primitive mammal belonging to the order Eutriconodonta, and which lived in present-day China during the Middle Cretaceous about 125 million years ago. Only one specimen has been formally described. This specimen (the holotype) consists of a virtually complete articulated skull and skeleton, it shared its corporal characteristics with most other Mesozoic mammals; it was a long-tailed, nocturnal tetrapod (with prehensile fingers and toes) which hunted insects, its food, during the night. It is suspected to be a Nocturnality, nocturnal creature because it had very large eyes which were roughly 5 mm across. This would have allowed it to have better night vision for catching insects. It is notable for its relatively derived forelimb morphology, having shoulder blades and other pectoral girdle elements comparable to those of modern therians like opossums. It also had grasping hands. By contrast, however, the hindlimbs retained primitive characters, suggestin ... [...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 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 non Stein 1859 'Phascolodon'' Simpson 1925; ''Phascolotheridium'' Cifelli & Dykes 2001***Species †'' Comodon gidleyi'' (Simpson 1925) Kretzoi & Kretzoi 2000 'Phascolodon gidleyi'' Simpson 1925; ''Phascolotheridium gidleyi'' (Simpson 1925) Cifelli & Dykes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amphilestidae
Amphilestidae is a family of Mesozoic mammals, generally regarded as eutriconodonts. They may form a paraphyletic or polyphyletic assemblage, though they share with gobiconodontids their similar tooth occlusion patterns and may be especially closely related to them. They occur from the Middle Jurassic to Cenomanian, and have a distribution across Laurasia. The putative amphilestid '' Tendagurodon'' is considered a non-amphilestid member of Amphilestheria along with the newly described ''Condorodon ''Condorodon'' is a genus of extinct mammals from the Lower Jurassic Cañadón Asfalto Formation of the Cañadón Asfalto Basin in Patagonia, Argentina. The type species is ''C. spanios'', described by Gaetano and Rougier in 2012. Classificati ...'' by Gaetano and Rougier (2012).L. C. Gaetano and G. W. Rougier. 2012. First amphilestid from South America: a molariform from the Jurassic Cañadón Asfalto Formation, Patagonia, Argentina. Journal of Mammalian Evolution References ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
