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Bocaconodon
''Bocaconodon'' (meaning "La Boca conical tooth") is an early mammaliaform genus that lived during the Pliensbachian (Early Jurassic) of Mexico. The type and only species, ''Bocaconodon tamaulipensis'' (referring to Tamaulipas, where the holotype was found), was named and described in 2008. It is known from a single specimen, a partial right dentary bone preserving two nearly complete molar teeth and the rear portion of a third molar. The specimen was found at the Huizachal Canyon locality, "a Pliensbachian floodplain siltstone in the La Boca Formation". Description The only known specimen of ''Bocaconodon'' (IGM 6617) is a partial right dentary bone, which preserves most of the last two molar teeth and the rear portion of a third molar. The preserved part of the dentary was quite thin from top to bottom, with the thinnest part being beneath the last molar. Behind the tooth row there was a facet that may have housed the coronoid bone. At the rear end of the dentary, there wa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
La Boca Formation
The La Boca Formation is a geological formation in Tamaulipas state, northeast Mexico. It was thought to date back to the Early Jurassic, concretely the Pliensbachian stage epoch. Although, the latest studies had proven that the local Vulcanism, related to the aperture of the Atlantic Ocean and the several Rift Events, that continue until the Bajocian, while the unit itself was likely deposited between the earliest Pliensbachian, as proven by zircon (189.0 ± 0.2 Ma) with the fossil taxa deposited on the rocks above, likely of Late Pliensbachian-Lower Toarcian age, and the upper section of Late Toarcian-Late Aalenian age. Due to successions of Aalenian depositional sistems on the upper layers of the Huizachal Canyon, has been delimited the formation to the Toarcian stage, being the regional equivalent of the Moroccan Azilal Formation. In North America, ''La Boca Formation'' was found to be a regional equivalent of the Eagle Mills redbeds of southern United States, the Todos Santo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mammaliaform
Mammaliaformes ("mammalian forms") is a clade that contains the crown group mammals and their closest extinct relatives; the group radiated from earlier probainognathian cynodonts. It is defined as the clade originating from the most recent common ancestor of Morganucodonta and the crown group mammals; the latter is the clade originating with the most recent common ancestor of extant Monotremata, Marsupialia, and Placentalia. Besides Morganucodonta and the crown group mammals, Mammaliaformes includes Docodonta and '' Hadrocodium'' as well as the Triassic ''Tikitherium'', the earliest known member of the group. Mammaliaformes is a term of phylogenetic nomenclature. In contrast, the assignment of organisms to Mammalia has traditionally been founded on traits and, on this basis, Mammalia is slightly more inclusive than Mammaliaformes. In particular, trait-based taxonomy generally includes '' Adelobasileus'' and '' Sinoconodon'' in Mammalia, though they fall outside the Mamm ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pliensbachian
The Pliensbachian is an age of the geologic timescale and stage in the stratigraphic column. It is part of the Early or Lower Jurassic Epoch or Series and spans the time between 190.8 ± 1.5 Ma and 182.7 ± 1.5 Ma (million years ago). The Pliensbachian is preceded by the Sinemurian and followed by the Toarcian. The Pliensbachian ended with the extinction event called the Toarcian turnover. During the Pliensbachian, the middle part of the Lias was deposited in Europe. The Pliensbachian is roughly coeval with the Charmouthian regional stage of North America. Stratigraphic definitions The Pliensbachian takes its name from the hamlet of Pliensbach in the community of Zell unter Aichelberg in the Swabian Alb, some 30 km east of Stuttgart in Germany. The name was introduced into scientific literature by German palaeontologist Albert Oppel in 1858. The base of the Pliensbachian is at the first appearances of the ammonite species '' Bifericeras donovani'' and gene ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Haldanodon
''Haldanodon'' is an extinct docodont mammaliaform which lived in the Upper Jurassic (Kimmeridgian, about 145 million years ago). Its fossil remains have been found in Portugal, in the well-known fossil locality of Guimarota, which is in the Alcobaça Formation. It may have been a semi-aquatic burrowing insectivore, similar in habits to desmans and the platypus. Several specimens are known, include a partial skeleton and well-preserved skulls. Description ''Haldanodon'' was about as long as a desman, and may have had a similar ecology. The skull was low and triangular when seen from above. For many years it had the best-known skull material of any docodont, making it vital for understanding the taxonomic position of that mammaliaform group. It was the first Mesozoic mammaliaform discovered to possess turbinal plates, a complex feature of mammalian nasal cavities. However, it also retained some curiously primitive traits in common with non-mammaliaform cynodonts. The body wa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Docodon
''Docodon'' (meaning 'beam tooth') was a mammaliaform from the Late Jurassic of western North America. It was the first docodontan cynodont to be named. Description ''Docodon'' was the first docodontan cynodont found and named, and later gave its name to the family Docodontidae as well as the order Docodonta.Kretzoi, M. (1946). "On Docodonta, a new order of Jurassic Mammals". ''Anneles Historico-Naturales Musei Nationalis Hungarici''. 39 :108-111. Docodonts had more complex shaped teeth than other early non-mammalian mammaliaforms, with piercing and crushing surfaces that would have allowed members of this family to eat a wider range of food types. These complex teeth are more similar to those of later mammal groups, but evolved independently of them. Unlike many of its coexisting mammal relatives from the Mesozoic, ''Docodon'' is known from a large number of teeth and jaws of differing growth stages. This has made it possible to study the growth of this docodontan, and has re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dinnetherium
''Dinnetherium'' is an extinct genus of morganucodont mammaliaform that is part of the monotypic order Dinnetheria and is also part of the monotypic family Dinnetheriidae.A. O. Averianov and A. V. Lopatin. 2011. Phylogeny of Triconodonts and Symmetrodonts and the Origin of Extant Mammals. Doklady Biological Sciences 436:32-35 The type species, ''D. nezorum'', was named in 1983. It was discovered in a Sinemurian layer of the Kayenta Formation,Sues H.-D., Clark J. M., et al (1994) A review of the Early Jurassic tetrapods from the Glen Canyon Group of the American Southwest., In the Shadow of the Dinosaurs: Early Mesozoic Tetrapods, N. C. Fraser and H.-D. Sues (eds.), Cambridge University Press, 284-294 within the Gold Spring Quarry 1, in Arizona. The holotype A holotype is a single physical example (or illustration) of an organism, known to have been used when the species (or lower-ranked taxon) was formally described. It is either the single such physical example (or illu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Woutersia
''Woutersia'' was a Triassic genus of ' symmetrodont' and the only representative of the family Woutersiidae. It was originally classified as a kuehneotheriid, but it has been suggested that it may be related to Docodonta. Remains of ''W. mirabilis'' and ''W. butleri'' have been found in the Gres à Avicula contorta Formation at Saint-Nicolas-de-Port, France, while ''W. mirabilis'' has been found in Varangéville, France; remains have been dated to the Late Triassic The Late Triassic is the third and final epoch (geology), epoch of the Triassic geologic time scale, Period in the geologic time scale, spanning the time between annum, Ma and Ma (million years ago). It is preceded by the Middle Triassic Epoch ..., 205.6 to 201.6 Ma. References Prehistoric mammaliaforms Prehistoric cynodont genera Rhaetian life Late Triassic synapsids of Europe Triassic France Fossils of France Fossil taxa described in 1983 Taxa named by Denise Sigogneau‐Russell {{paleo-thera ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kuehneotherium
''Kuehneotherium'' is an early mammaliaform genus, previously considered a holothere, that lived during the Late Triassic-Early Jurassic Epochs and is characterized by reversed-triangle pattern of molar cusps. Although many fossils have been found, the fossils are limited to teeth, dental fragments, and mandible fragments. The genus includes ''Kuehneotherium praecursoris'' and all related species. It was first named and described by Doris M. Kermack, K. A. Kermack, and Frances Mussett in November 1967. The family Kuehneotheriidae and the genus ''Kuehneotherium'' were created to house the single species ''Kuehneotherium praecursoris''. Modeling based upon a comparison of the ''Kuehneotherium'' jaw with other mammaliaforms indicates it was about the size of a modern-day shrew between 4 and 5.5 g at adulthood. ''Kuehneotherium'' is thought to be an insectivore that could consume only soft-bodied insects such as moths. Its teeth were shaped for vertical shearing and could not crush ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Megazostrodon
''Megazostrodon'' is an extinct genus of basal mammaliaforms belonging to the order Morganucodonta. It is approximately 200 million years old.Fur and Fangs: Mammal Origins . Palaeobiology and Biodiversity Research Group, University of Bristol. Two species are known: ''M. rudnerae'' from the of and , and ''M. chenali'' from the |
Erythrotherium
''Erythrotherium'' (meaning "red beast") is an extinct genus of basal mammaliaforms from the Late Triassic to Lower Jurassic. It is related to ''Morganucodon''. Only one species is recorded, ''Erythrotherium parringtoni'', from Red Beds, Stormberg Group, Mafeteng, Upper Elliot and Clarens Formations, from Lesotho and South Africa South Africa, officially the Republic of South Africa (RSA), is the southernmost country in Africa. It is bounded to the south by of coastline that stretch along the South Atlantic and Indian Oceans; to the north by the neighbouring count .... The single jaw of ''Erythrotherium'' was found in the matrix surrounding a dinosaur fossil, by the person preparing the dinosaur, Mr C. Gow. References Morganucodonts Triassic synapsids of Africa Jurassic synapsids of Africa Triassic South Africa Jurassic South Africa Fossils of South Africa Fossil taxa described in 1964 Taxa named by Alfred W. Crompton Prehistoric cynodont genera {{ ... [...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 ( ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Morganucodont
Morganucodonta (" Glamorgan teeth") is an extinct order of basal Mammaliaformes, a group including crown-group mammals (Mammalia) and their close relatives. Their remains have been found in Southern Africa, Western Europe, North America, India and China. The morganucodontans were probably insectivorous and nocturnal, though like eutriconodonts some species attained large sizes and were carnivorous. Nocturnality is believed to have evolved in the earliest mammals in the Triassic (called the nocturnal bottleneck) as a specialisation that allowed them to exploit a safer, night-time niche, while most larger predators were likely to have been active during the day (though some dinosaurs, for example, were nocturnal as well). Anatomy and biology Morganucodontans had a double jaw articulation made up of the dentary-squamosal joint as well as a quadrate-articular one. This implies that they also retained one of their postdentary bones: the articular. There is a trough at the back o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
