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Gongbusaurus
''Gongbusaurus'' is a genus of ornithischian, perhaps ornithopod, dinosaur that lived between about 160 and 157 million years ago, in the Late Jurassic period. A small herbivore, it is very poorly known. Two species have been assigned to it, but as the original name is based on teeth, there is no concrete evidence to connect the two species. Its fossils have been found in China. Description ''Gongbusaurus'', by extrapolation from the remains of possible species "G." ''wucaiwanensis'' and other basal ornithopods, was a herbivorous bipedal animal around long. The tibia of "G." ''wucaiwanensis'' is 19.5 centimetres long. It would have been a strong runner. Classification Dong Zhiming, Zhou Shiwu, and Zhang Zicheng, who originally described the type species ''G. shiyii'', thought it was most similar to ''Fabrosaurus'' and assigned it to the nebulous Fabrosauridae. Upon description of the second species "G." ''wucaiwanensis'' several years later, Dong elected to assign it to Hypsi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gongbusaurus Wucaiwanensis
''Gongbusaurus'' is a genus of ornithischian, perhaps ornithopod, dinosaur that lived between about 160 and 157 million years ago, in the Late Jurassic period. A small herbivore, it is very poorly known. Two species have been assigned to it, but as the original name is based on teeth, there is no concrete evidence to connect the two species. Its fossils have been found in China. Description ''Gongbusaurus'', by extrapolation from the remains of possible species "G." ''wucaiwanensis'' and other basal ornithopods, was a herbivorous bipedal animal around long. The tibia of "G." ''wucaiwanensis'' is 19.5 centimetres long. It would have been a strong runner. Classification Dong Zhiming, Zhou Shiwu, and Zhang Zicheng, who originally described the type species ''G. shiyii'', thought it was most similar to ''Fabrosaurus'' and assigned it to the nebulous Fabrosauridae. Upon description of the second species "G." ''wucaiwanensis'' several years later, Dong elected to assign it to Hypsi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Upper Shaximiao Formation
The Shaximiao Formation () is a Middle to Late Jurassic aged geological formation in Sichuan, China, most notable for the wealth of dinosaurs fossils that have been excavated from its strata. The Shaximiao Formation is exposed in and around the small township of Dashanpu (), situated seven kilometres north-east from Sichuan's third largest city, Zigong, in the Da'an District. Geology The Shaximiao Formation includes two distinct subunits: The upper and lower Shaximiao Formations (), although they are commonly referred to as one, simply being called the "Shaximiao Formation". The upper Shaximiao Formation is also known as the Shangshaximiao Formation, and the lower Shaximiao Formation is also known as the Xiashaximiao Formation, which are direct transliterations of the Chinese names. Both subunits primarily consist of purple-red mudstones, with variable sand inclusion. and siltstones with interbedded sandstones. Dinosaur finds The Shaximiao Formation has produced mainly ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Late Jurassic
The Late Jurassic is the third epoch of the Jurassic Period, and it spans the geologic time from 163.5 ± 1.0 to 145.0 ± 0.8 million years ago (Ma), which is preserved in Upper Jurassic strata.Owen 1987. In European lithostratigraphy, the name "Malm" indicates rocks of Late Jurassic age. In the past, ''Malm'' was also used to indicate the unit of geological time, but this usage is now discouraged to make a clear distinction between lithostratigraphic and geochronologic/chronostratigraphic units. Subdivisions The Late Jurassic is divided into three ages, which correspond with the three (faunal) stages of Upper Jurassic rock: Paleogeography During the Late Jurassic Epoch, Pangaea broke up into two supercontinents, Laurasia to the north, and Gondwana to the south. The result of this break-up was the spawning of the Atlantic Ocean. However, at this time, the Atlantic Ocean was relatively narrow. Life forms of the epoch This epoch is well known for many famous types of dinosau ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Synapomorphy
In phylogenetics, an apomorphy (or derived trait) is a novel character or character state that has evolved from its ancestral form (or plesiomorphy). A synapomorphy is an apomorphy shared by two or more taxa and is therefore hypothesized to have evolved in their most recent common ancestor. ) In cladistics, synapomorphy implies homology. Examples of apomorphy are the presence of erect gait, fur, the evolution of three middle ear bones, and mammary glands in mammals but not in other vertebrate animals such as amphibians or reptiles, which have retained their ancestral traits of a sprawling gait and lack of fur. Thus, these derived traits are also synapomorphies of mammals in general as they are not shared by other vertebrate animals. Etymology The word —coined by German entomologist Willi Hennig—is derived from the Ancient Greek words (''sún''), meaning "with, together"; (''apó''), meaning "away from"; and (''morphḗ''), meaning "shape, form". Clade analysis T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oxfordian Stage
The Oxfordian is, in the ICS' geologic timescale, the earliest age of the Late Jurassic Epoch, or the lowest stage of the Upper Jurassic Series. It spans the time between 163.5 ± 1.0 Ma and 157.3 ± 1.0 Ma (million years ago). The Oxfordian is preceded by the Callovian and is followed by the Kimmeridgian. Stratigraphic definitions The Oxfordian Stage was called "Clunch Clay and Shale" by William Smith (1815–1816); in 1818 W. Buckland described them under the unwieldy title "Oxford, Forest or Fen Clay". The term Oxfordian was introduced by Alcide d'Orbigny in 1844. The name is derived from the English city of Oxford, where the beds are well developed, but they crop out almost continuously from Dorset to the coast of Yorkshire, generally forming low, broad valleys. They are well exposed at Weymouth, Oxford, Bedford, Peterborough, and in the cliffs at Scarborough, Red Cliff and Gristhorpe Bay. Rocks of this age are found also in Uig and Skye. The base of the Oxfordian Stage i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Maxilla
The maxilla (plural: ''maxillae'' ) in vertebrates is the upper fixed (not fixed in Neopterygii) bone of the jaw formed from the fusion of two maxillary bones. In humans, the upper jaw includes the hard palate in the front of the mouth. The two maxillary bones are fused at the intermaxillary suture, forming the anterior nasal spine. This is similar to the mandible (lower jaw), which is also a fusion of two mandibular bones at the mandibular symphysis. The mandible is the movable part of the jaw. Structure In humans, the maxilla consists of: * The body of the maxilla * Four processes ** the zygomatic process ** the frontal process of maxilla ** the alveolar process ** the palatine process * three surfaces – anterior, posterior, medial * the Infraorbital foramen * the maxillary sinus * the incisive foramen Articulations Each maxilla articulates with nine bones: * two of the cranium: the frontal and ethmoid * seven of the face: the nasal, zygomatic, lacrimal, inferior n ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Premaxilla
The premaxilla (or praemaxilla) is one of a pair of small cranial bones at the very tip of the upper jaw of many animals, usually, but not always, bearing teeth. In humans, they are fused with the maxilla. The "premaxilla" of therian mammal has been usually termed as the incisive bone. Other terms used for this structure include premaxillary bone or ''os premaxillare'', intermaxillary bone or ''os intermaxillare'', and Goethe's bone. Human anatomy In human anatomy, the premaxilla is referred to as the incisive bone (') and is the part of the maxilla which bears the incisor teeth, and encompasses the anterior nasal spine and alar region. In the nasal cavity, the premaxillary element projects higher than the maxillary element behind. The palatal portion of the premaxilla is a bony plate with a generally transverse orientation. The incisive foramen is bound anteriorly and laterally by the premaxilla and posteriorly by the palatine process of the maxilla. It is formed from the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Institute Of Vertebrate Paleontology And Paleoanthropology
The Institute of Vertebrate Paleontology and Paleoanthropology (IVPP; ) of China is a research institution and collections repository for fossils, including many dinosaur and pterosaur specimens (many from the Yixian Formation). As its name suggests, research is focused on both paleontological topics and those relating to human prehistory. The institution, located in Beijing, grew out of the Cenozoic Research Laboratory in 1929 and is its own institution under the Chinese Academy of Sciences. Its staff have increasingly worked internationally, participating in the China-Canada Dinosaur Project from 1986 to 1991 and authoring or coauthoring forty-five ''Nature'' and ''Science'' articles from 1999 to 2005. Notable paleontologists who have been affiliated with the IVPP include Yang Zhongjian (also known as C. C. Young), Dong Zhiming, Meemann Chang and Zhao Xijin Zhao Xijin (赵喜进; born c. 1935 died July 21, 2012) was a Chinese paleontologist notable for having named numerous di ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 illustration) or one of several examples, but explicitly designated as the holotype. Under the International Code of Zoological Nomenclature (ICZN), a holotype is one of several kinds of name-bearing types. In the International Code of Nomenclature for algae, fungi, and plants (ICN) and ICZN, the definitions of types are similar in intent but not identical in terminology or underlying concept. For example, the holotype for the butterfly '' Plebejus idas longinus'' is a preserved specimen of that subspecies, held by the Museum of Comparative Zoology at Harvard University. In botany, an isotype is a duplicate of the holotype, where holotype and isotypes are often pieces from the same individual plant or samples from the same gathering. A holotype is not necessarily "typ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ankylosauria
Ankylosauria is a group of herbivorous dinosaurs of the order Ornithischia. It includes the great majority of dinosaurs with armor in the form of bony osteoderms, similar to turtles. Ankylosaurs were bulky quadrupeds, with short, powerful limbs. They are known to have first appeared in the Middle Jurassic, and persisted until the end of the Cretaceous Period. The two main families of Ankylosaurs, Nodosauridae and Ankylosauridae are primarily known from the Northern Hemisphere, but the more basal Parankylosauria are known from southern Gondwana during the Cretaceous. Ankylosauria was first named by Henry Fairfield Osborn in 1923.Osborn, H. F. (1923). "Two Lower Cretaceous dinosaurs of Mongolia." ''American Museum Novitates'', 95: 1–1/ref> In the Linnaean classification system, the group is usually considered either a suborder or an infraorder. It is contained within the group Thyreophora, which also includes the stegosaurs, armored dinosaurs known for their combination of plate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gastonia (dinosaur)
''Gastonia'' is a genus of herbivorous ankylosaurian dinosaur from the Early Cretaceous of North America, around 139 to 125 million years ago. It is often considered a nodosaurid closely related to ''Polacanthus''. ''Gastonia'' has a sacral shield and large shoulder spikes. Discovery and species The type specimen of ''Gastonia burgei'' ( CEUM 1307) was discovered in a bonebed from the limestone strata of the lower Cedar Mountain Formation in Yellow Cat Quarry, Grand County, eastern Utah, the type specimen consisting of a single skull. The type specimen was found alongside 4 partial skeletons of ''Gastonia that'' were placed as paratypes, along with the type specimen of ''Utahraptor'' and an Iguanodontid. ''Gastonia'' is among the most common dinosaur fossils in the Cedar Mountain Formation, with many individuals being found across several quarries in the southwest.Kirkland, J.I. (1998). A polacanthine ankylosaur (Ornithischia: Dinosauria) from the Early Cretaceous (Barremian) o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sarcolestes
''Sarcolestes'' (meaning "flesh robber") is an extinct genus of ankylosaurian ornithischian dinosaur from the Oxford Clay of England. The current type and only species is ''S. leedsi'', and the holotype is a single partial left mandible. The genus and species were named in 1893 by Richard Lydekker, who thought they belonged to a theropod. Discovery ''Sarcolestes'' was first named in 1893 by Richard Lydekker, and its type species was designated as ''S. leedsi''. The specific name was to honour Alfred Nicholson Leeds, the discoverer of the specimen, and many others like it. The holotype and only specimen, is a partial left mandible and fused scute that was damaged during excavation. The jaw preserved one entire tooth and two crown tips in its alveolus, with the missing bone in the central section of the mandible. It lacks a preserved predentary, even though the entire mandibular symphysis is preserved and complete. Classification Originally, Lydekker found that ''Sarcolestes'' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
