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Eotrachodon
''Eotrachodon orientalis'' (meaning "dawn ''Trachodon'' from the east") is a species of hadrosaurid that was 2016 in paleontology, described in 2016. The holotype was found in the Mooreville Chalk Formation (Upper Santonian) in Alabama in 2007 and includes a well-preserved skull and partial skeleton, making it a rare find among dinosaurs of Appalachia (Mesozoic), Appalachia. Another primitive hadrosaur, ''Lophorhothon'', is also known from the same formation, although ''Eotrachodon'' lived a few million years prior. A phylogenetic study has found ''Eotrachodon'' to be the sister taxon to the hadrosaurid subfamilies Lambeosaurinae and Saurolophinae. This, along with the other Appalachian hadrosaur ''Hadrosaurus'' and possibly ''Lophorhothon'', ''Claosaurus'' and Hypsibema missouriensis, both species of ''Hypsibema'', suggests that Appalachia was the ancestral area of Hadrosauridae. See also * Timeline of hadrosaur research *2016 in paleontology References Further reading [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hadrosauridae
Hadrosaurids (), also hadrosaurs or duck-billed dinosaurs, are members of the ornithischian family Hadrosauridae. This group is known as the duck-billed dinosaurs for the flat duck-bill appearance of the bones in their snouts. The ornithopod family, which includes genera such as '' Edmontosaurus'' and '' Parasaurolophus'', was a common group of herbivores during the Late Cretaceous Period. Hadrosaurids are descendants of the Late Jurassic/Early Cretaceous iguanodontian dinosaurs and had a similar body layout. Hadrosaurs were among the most dominant herbivores during the Late Cretaceous in Asia and North America, and during the close of the Cretaceous several lineages dispersed into Europe, Africa, and South America. Like other ornithischians, hadrosaurids had a predentary bone and a pubic bone which was positioned backwards in the pelvis. Unlike more primitive iguanodonts, the teeth of hadrosaurids are stacked into complex structures known as dental batteries, which acted as e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mooreville Chalk
The Mooreville Chalk is a geological formation in North America, within the U.S. states of Alabama and Mississippi, which were part of the subcontinent of Appalachia Appalachia ( ) is a geographic region located in the Appalachian Mountains#Regions, central and southern sections of the Appalachian Mountains in the east of North America. In the north, its boundaries stretch from the western Catskill Mountai .... The strata date back to the early Santonian to the early Campanian Stage (stratigraphy), stage of the Late Cretaceous. The chalk was formed by pelagic sediments deposited along the eastern edge of the Mississippi embayment. It is a unit of the Selma Group and consists of the upper Arcola Limestone Member and an unnamed lower member. Dinosaur, mosasaur, and primitive bird remains are among the fossils that have been recovered from the Mooreville Chalk Formation.Weishampel, David B; et al. (2004). "Dinosaur distribution (Late Cretaceous, North America)." In: Weishampel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mooreville Chalk Formation
The Mooreville Chalk is a geological formation in North America, within the U.S. states of Alabama and Mississippi, which were part of the subcontinent of Appalachia. The strata date back to the early Santonian to the early Campanian stage of the Late Cretaceous. The chalk was formed by pelagic sediments deposited along the eastern edge of the Mississippi embayment. It is a unit of the Selma Group and consists of the upper Arcola Limestone Member and an unnamed lower member. Dinosaur, mosasaur, and primitive bird remains are among the fossils that have been recovered from the Mooreville Chalk Formation.Weishampel, David B; et al. (2004). "Dinosaur distribution (Late Cretaceous, North America)." In: Weishampel, David B.; Dodson, Peter; and Osmólska, Halszka (eds.): The Dinosauria, 2nd, Berkeley: University of California Press. Pp. 574-588. . Fish Cartilaginous fish Bony fish Reptiles Dinosaurs Indeterminate hadrosaurid, nodosaurid, dinosaur egg, and ornithomimosaur fossil ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Appalachia (Mesozoic)
During most of the Late Cretaceous (100.5 to 66 million years ago) the eastern half of North America formed Appalachia (named for the Appalachian Mountains), an island land mass separated from Laramidia to the west by the Western Interior Seaway. This seaway had split North America into two massive landmasses due to a multitude of factors such as tectonism and sea-level fluctuations for nearly 40 million years. The seaway eventually expanded, divided across the Dakotas, and by the end of the Cretaceous, it retreated towards the Gulf of Mexico and the Hudson Bay. This left the island masses joined in the continent of North America as the Rocky Mountains rose. From the Cenomanian to the end of the Campanian ages of the Late Cretaceous, Appalachia was separated from the rest of North America. As the Western Interior Seaway retreated in the Maastrichtian, Laramidia and Appalachia eventually connected. Until this connection, its fauna was isolated, and developed very differently from ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lophorhothon
''Lophorhothon'' is a genus of hadrosauroid dinosaur from the Late Cretaceous of Alabama, Georgia (US state), Georgia, and North Carolina. It was the first genus of dinosaur discovered in Alabama, in the United States. Discovery and naming Remains of a small, poorly known perhaps Hadrosaurid, saurolophine dinosaur were first discovered during the 1940s, from extensive erosional outcrops of the lower unnamed member of the Mooreville Chalk Formation (Selma Group; lower and middle Campanian) in Dallas County, Alabama, Dallas County, west of the town of Selma, Alabama. The taxon has since also been reported from Black Creek Formation (Campanian) of North Carolina. The holotype, which is housed in the collections of the Field Museum of Natural History, Field Museum in Chicago, consists of a fragmentary and disarticulated skull and incomplete postcranial skeleton. The length on the holotype specimen has been estimated as . Which is small for a hadrosaur, but the original specimen is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Timeline Of Hadrosaur Research
This timeline of hadrosaur research is a chronological listing of events in the History of paleontology, history of paleontology focused on the hadrosauroids, a group of herbivorous ornithopod dinosaurs popularly known as the duck-billed dinosaurs. Scientific research on hadrosaurs began in the :1850s in paleontology, 1850s, when Joseph Leidy described the genera ''Thespesius'' and ''Trachodon'' based on scrappy fossils History of paleontology in the United States, discovered Paleontology in the United States, in the western United States. Just two years later he published a description of the much better-preserved remains of an animal Paleontology in New Jersey, from New Jersey that he named ''Hadrosaurus''. The early :20th century in paleontology, 20th century saw such a boom in hadrosaur discoveries and research that paleontologists' knowledge of these dinosaurs "increased by virtually an order of magnitude" according to a 2004 in paleontology, 2004 review by John R. Horner, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trachodon
''Trachodon'' (meaning "rough tooth") is a dubious genus of hadrosaurid dinosaur based on teeth from the Campanian-age Upper Cretaceous Judith River Formation of Montana, U.S.Leidy, J. (1856). "Notice of remains of extinct reptiles and fishes, discovered by F. V. Hayden in the Bad Lands of the Judith River, Nebraska Territories." ''Proceedings of the Academy of Natural Science Philadelphia'', 8(25 March): 72–73. It is a historically important genus with a convoluted taxonomy that has been all but abandoned by modern dinosaur paleontologists.Creisler, B.S. (2007). Deciphering duckbills. in: K. Carpenter (ed.), ''Horns and Beaks: Ceratopsian and Ornithopod Dinosaurs''. Indiana University Press: Bloomington and Indianapolis, 185–210. Despite being used for decades as the iconic duckbill dinosaur, the material it is based on is composed of teeth from both duckbills and ceratopsids (their teeth have a distinctive double rootHatcher, J.B., Marsh, O.C. and Lull, R.S. (1907). ''T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Late Cretaceous
The Late Cretaceous (100.5–66 Ma) is the more recent of two epochs into which the Cretaceous Period is divided in the geologic time scale. Rock strata from this epoch form the Upper Cretaceous Series. The Cretaceous is named after ''creta'', the Latin word for the white limestone known as chalk. The chalk of northern France and the white cliffs of south-eastern England date from the Cretaceous Period. Climate During the Late Cretaceous, the climate was warmer than present, although throughout the period a cooling trend is evident. The tropics became restricted to equatorial regions and northern latitudes experienced markedly more seasonal climatic conditions. Geography Due to plate tectonics, the Americas were gradually moving westward, causing the Atlantic Ocean to expand. The Western Interior Seaway divided North America into eastern and western halves; Appalachia and Laramidia. India maintained a northward course towards Asia. In the Southern Hemisphere, Aus ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Campanian Dinosaurs
The Campanian is the fifth of six ages of the Late Cretaceous epoch on the geologic timescale of the International Commission on Stratigraphy (ICS). In chronostratigraphy, it is the fifth of six stages in the Upper Cretaceous Series. Campanian spans the time from 83.6 (± 0.2) to 72.1 (± 0.2) million years ago. It is preceded by the Santonian and it is followed by the Maastrichtian. The Campanian was an age when a worldwide sea level rise covered many coastal areas. The morphology of some of these areas has been preserved: it is an unconformity beneath a cover of marine sedimentary rocks. Etymology The Campanian was introduced in scientific literature by Henri Coquand in 1857. It is named after the French village of Champagne in the department of Charente-Maritime. The original type locality was a series of outcrops near the village of Aubeterre-sur-Dronne in the same region. Definition The base of the Campanian Stage is defined as a place in the stratigraphic column wh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dinosaur Genera
Dinosaurs are a diverse group of reptiles of the clade Dinosauria. They first appeared during the Triassic Geological period, period, between 243 and 233.23 million years ago (mya), although the exact origin and timing of the #Evolutionary history, evolution of dinosaurs is a subject of active research. They became the dominant terrestrial vertebrates after the Triassic–Jurassic extinction event 201.3 mya and their dominance continued throughout the Jurassic and Cretaceous periods. The fossil record shows that birds are feathered dinosaurs, Evolution of birds, having evolved from earlier Theropoda, theropods during the Late Jurassic epoch, and are the only dinosaur lineage known to have survived the Cretaceous–Paleogene extinction event approximately 66 mya. Dinosaurs can therefore be divided into avian dinosaurs—birds—and the extinct non-avian dinosaurs, which are all dinosaurs other than birds. Dinosaurs are varied from taxonomy (biology), taxonomic, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
