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Heishansaurus
''Heishansaurus'', meaning "Heishan lizard" after the area in China where it was discovered, is the name given to a dubious genus of herbivorous ornithischian dinosaur, probably belonging to the Ankylosauridae. In 1930, Swedish palaeontologist Anders Birger Bohlin discovered dinosaur fossils, in the context of the Swedish-Chinese expeditions headed by Sven Hedin, near Jiayuguan ("Chia-Yu-Kuan"), in the west of Gansu Province. In 1953, Bohlin named these as the type species ''Heishansaurus pachycephalus''. The generic name refers to the Heishan, the "Black Mountains". The specific name ''pachycephalus'', meaning "thick-headed", was inspired by Bohlin's identification of the taxon as a pachycephalosaur.B. Bohlin, 1953, ''Fossil reptiles from Mongolia and Kansu. Reports from the Scientific Expedition to the North-western Provinces of China under Leadership of Dr. Sven Hedin. VI. Vertebrate Palaeontology 6.'' The Sino-Swedish Expedition Publications 37, 113 pp Today this dinosaur ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pinacosaurus
''Pinacosaurus'' (meaning "Plank lizard") is a genus of ankylosaurid thyreophoran dinosaur that lived in Asia during the Late Cretaceous (Santonian-Campanian, roughly 75 million to 71 million years ago), mainly in Mongolia and China. The first remains of the genus were found in 1923, and the type species ''Pinacosaurus grangeri'' was named in 1933. ''Pinacosaurus mephistocephalus'' named in 1999, is a second possibly valid species differing from the type species in details of the skull armour. Of ''Pinacosaurus grangeri'' many skeletons have been found, more than of any other ankylosaur. These predominantly consist of juveniles that perhaps lived in herds roaming the desert landscape of their habitat. ''Pinacosaurus'' was a medium-sized ankylosaurine, about five metres long and weighed up to two tonnes. Its body was flat and low-slung but not as heavily built as in some other members of the Ankylosaurinae. The head was protected by bone tiles, hence its name. Each nostril was for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Minhe Formation
The Minhe Formation () is a geological formation in northwestern China, whose strata date back to the Late Cretaceous period. Dinosaur remains are among the fossils that have been recovered from the formation.Weishampel, David B; et al. (2004). "Dinosaur distribution (Late Cretaceous, Asia)." In: Weishampel, David B.; Dodson, Peter; and Osmólska, Halszka (eds.): The Dinosauria, 2nd, Berkeley: University of California Press. Pp. 593-600. . Vertebrate paleofauna Dinosaurs A tyrannosaur tooth with a split carina has been recovered from the Minhe Formation in China. See also * List of dinosaur-bearing rock formations This list of dinosaur-bearing rock formations is a list of geologic formations in which dinosaur fossils have been documented. Containing body fossils * List of stratigraphic units with dinosaur body fossils ** List of stratigraphic units with few ... References Bibliography * Molnar, R. E., 2001, Theropod paleopathology: a literature survey: In: Mesozoi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Campanian
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 outcrop 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 wher ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nomen Dubium
In binomial nomenclature, a ''nomen dubium'' (Latin for "doubtful name", plural ''nomina dubia'') is a scientific name that is of unknown or doubtful application. Zoology In case of a ''nomen dubium'' it may be impossible to determine whether a specimen belongs to that group or not. This may happen if the original type series (i. e. holotype, isotype, syntype or paratype) is lost or destroyed. The zoological and botanical codes allow for a new type specimen, or neotype, to be chosen in this case. A name may also be considered a ''nomen dubium'' if its name-bearing type is fragmentary or lacking important diagnostic features (this is often the case for species known only as fossils). To preserve stability of names, the ''International Code of Zoological Nomenclature'' allows a new type specimen, or neotype, to be chosen for a ''nomen dubium'' in this case. 75.5. Replacement of unidentifiable name-bearing type by a neotype. When an author considers that the taxonomic identity of a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Junior Synonym
The Botanical and Zoological Codes of nomenclature treat the concept of synonymy differently. * In botanical nomenclature, a synonym is a scientific name that applies to a taxon that (now) goes by a different scientific name. For example, Linnaeus was the first to give a scientific name (under the currently used system of scientific nomenclature) to the Norway spruce, which he called ''Pinus abies''. This name is no longer in use, so it is now a synonym of the current scientific name, ''Picea abies''. * In zoology, moving a species from one genus to another results in a different binomen, but the name is considered an alternative combination rather than a synonym. The concept of synonymy in zoology is reserved for two names at the same rank that refers to a taxon at that rank - for example, the name ''Papilio prorsa'' Linnaeus, 1758 is a junior synonym of ''Papilio levana'' Linnaeus, 1758, being names for different seasonal forms of the species now referred to as ''Araschnia lev ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
American Museum Of Natural History
The American Museum of Natural History (abbreviated as AMNH) is a natural history museum on the Upper West Side of Manhattan in New York City. In Theodore Roosevelt Park, across the street from Central Park, the museum complex comprises 26 interconnected buildings housing 45 permanent exhibition halls, in addition to a planetarium and a library. The museum collections contain over 34 million specimens of plants, animals, fossils, minerals, rocks, meteorites, human remains, and human cultural artifacts, as well as specialized collections for frozen tissue and genomic and astrophysical data, of which only a small fraction can be displayed at any given time. The museum occupies more than . AMNH has a full-time scientific staff of 225, sponsors over 120 special field expeditions each year, and averages about five million visits annually. The AMNH is a private 501(c)(3) organization. Its mission statement is: "To discover, interpret, and disseminate—through scientific research and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Osteoderm
Osteoderms are bony deposits forming scales, plates, or other structures based in the dermis. Osteoderms are found in many groups of extant and extinct reptiles and amphibians, including lizards, crocodilians, frogs, temnospondyls (extinct amphibians), various groups of dinosaurs (most notably ankylosaurs and stegosaurians), phytosaurs, aetosaurs, placodonts, and hupehsuchians (marine reptiles with possible ichthyosaur affinities). Osteoderms are uncommon in mammals, although they have occurred in many xenarthrans (armadillos and the extinct glyptodonts and mylodontid and scelidotheriid ground sloths). The heavy, bony osteoderms have evolved independently in many different lineages. The armadillo osteoderm is believed to develop in subcutaneous dermal tissues. These varied structures should be thought of as anatomical analogues, not homologues, and do not necessarily indicate monophyly. The structures are however derived from scutes, common to all classes of amniotes and ... [...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] |
Scutes
A scute or scutum (Latin: ''scutum''; plural: ''scuta'' "shield") is a bony external plate or scale overlaid with horn, as on the shell of a turtle, the skin of crocodilians, and the feet of birds. The term is also used to describe the anterior portion of the mesonotum in insects as well as some arachnids (e.g., the family Ixodidae, the scale ticks). Properties Scutes are similar to scales and serve the same function. Unlike the scales of lizards and snakes, which are formed from the epidermis, scutes are formed in the lower vascular layer of the skin and the epidermal element is only the top surface . Forming in the living dermis, the scutes produce a horny outer layer that is superficially similar to that of scales. Scutes will usually not overlap as snake scales (but see the pangolin). The outer keratin layer is shed piecemeal, and not in one continuous layer of skin as seen in snakes or lizards. The dermal base may contain bone and produce dermal armour. Scutes with a bony ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dermal
The dermis or corium is a layer of skin between the epidermis (with which it makes up the cutis) and subcutaneous tissues, that primarily consists of dense irregular connective tissue and cushions the body from stress and strain. It is divided into two layers, the superficial area adjacent to the epidermis called the papillary region and a deep thicker area known as the reticular dermis.James, William; Berger, Timothy; Elston, Dirk (2005). ''Andrews' Diseases of the Skin: Clinical Dermatology'' (10th ed.). Saunders. Pages 1, 11–12. . The dermis is tightly connected to the epidermis through a basement membrane. Structural components of the dermis are collagen, elastic fibers, and extrafibrillar matrix.Marks, James G; Miller, Jeffery (2006). ''Lookingbill and Marks' Principles of Dermatology'' (4th ed.). Elsevier Inc. Page 8–9. . It also contains mechanoreceptors that provide the sense of touch and thermoreceptors that provide the sense of heat. In addition, hair follicles, s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Postcranial
Postcrania (postcranium, adjective: postcranial) in zoology and vertebrate paleontology is all or part of the skeleton apart from the skull. Frequently, fossil remains, e.g. of dinosaurs or other extinct tetrapods, consist of partial or isolated skeletal elements; these are referred to as ''postcrania''. There is some disagreement over whether the skull and skeleton belong to the same or different animals. One example is the case of a Cretaceous sauropod skull of ''Nemegtosaurus'' found in association with the postcranial skeleton ''Opisthocoelicaudia ''Opisthocoelicaudia'' is a genus of sauropod dinosaur of the Late Cretaceous Period discovered in the Gobi Desert of Mongolia. The type species is ''Opisthocoelicaudia skarzynskii''. A well-preserved skeleton lacking only the head and neck wa ...''. In paleoanthropological studies, reconstruction of relationship between various species/remains is considered to be better supported by cranial characters rather than postcranial c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cranium
The skull is a bone protective cavity for the brain. The skull is composed of four types of bone i.e., cranial bones, facial bones, ear ossicles and hyoid bone. However two parts are more prominent: the cranium and the mandible. In humans, these two parts are the neurocranium and the viscerocranium ( facial skeleton) that includes the mandible as its largest bone. The skull forms the anterior-most portion of the skeleton and is a product of cephalisation—housing the brain, and several sensory structures such as the eyes, ears, nose, and mouth. In humans these sensory structures are part of the facial skeleton. Functions of the skull include protection of the brain, fixing the distance between the eyes to allow stereoscopic vision, and fixing the position of the ears to enable sound localisation of the direction and distance of sounds. In some animals, such as horned ungulates (mammals with hooves), the skull also has a defensive function by providing the mount (on the fron ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
