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Xingxiulong
''Xingxiulong'' (meaning "Xingxiu Bridge dragon") is a genus of bipedal sauropodiform from the Early Jurassic of China. It contains a single species, ''X. chengi'', described by Wang ''et al.'' in 2017 from three specimens, two adults and an immature individual, that collectively constitute a mostly complete skeleton. Adults of the genus measured long and tall. Phylogenetic analysis suggests that ''Xingxiulong'' is most closely related to its contemporary ''Jingshanosaurus'', although an alternative position outside of both the Sauropodiformes and Massospondylidae is also plausible. Despite their close relationship, ''Xingxiulong'' prominently differs from ''Jingshanosaurus'' - and from most basal sauropodomorphs - in having a number of sauropod-like traits. These include a sacrum containing four vertebrae; a pubis with an exceptionally long top portion; and the femur, the first and fifth metatarsals on the foot, and the scapula being wide and robust. These probably rep ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Massospondylidae
Massospondylidae is a family of early massopod dinosaurs that existed in Asia, Africa, North America, South America and AntarcticaHellert, Spencer M. "A New Basal Sauropodomorph from The Early Jurassic Hanson Formation of Antarctica." Geological Society of America Abstracts with Programs,. Vol. 44. No. 5. 2012. during the Late Triassic to the Early Jurassic periods. Several dinosaurs have been classified as massospondylids over the years. The largest cladistic analysis of early sauropodomorphs, which was presented by Apaldetti and colleagues in November 2011, found '' Adeopapposaurus'', '' Coloradisaurus'', '' Glacialisaurus'', '' Massospondylus'', '' Leyesaurus'' and ''Lufengosaurus'' to be massospondylids. This result supports many previous analyses that tested fewer taxa. However, this analysis found the two recently described North American massopods, '' Sarahsaurus'' and '' Seitaad'', and the South African ''Ignavusaurus'' to nest outside Massospondylidae, as opposed to so ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Massopoda
Massopoda is a clade of sauropodomorph dinosaurs which lived during the Late Triassic to Late Cretaceous epochs. It was named by paleontologist Adam M. Yates of the University of the Witwatersrand in 2007. Massopoda is a stem-based taxon, defined as all animals more closely related to ''Saltasaurus loricatus'' than to ''Plateosaurus engelhardti''. The name Massopoda, ; , is also contraction of Massospondylidae and Sauropoda, two disparate taxa in the clade. Classification Yates assigned the Massopoda to Plateosauria. Within the clade, he assigned the families Massospondylidae (which includes the relatively well-known dinosaur ''Massospondylus'') and Riojasauridae (which includes ''Riojasaurus'') as well as the Sauropoda. The following is a cladogram A cladogram (from Greek ''clados'' "branch" and ''gramma'' "character") is a diagram used in cladistics to show relations among organisms. A cladogram is not, however, an evolutionary tree because it does not show how ancestors ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Massospondylus
''Massospondylus'' ( ; from Greek, (massōn, "longer") and (spondylos, "vertebra")) is a genus of sauropodomorph dinosaur from the Early Jurassic. (Hettangian to Pliensbachian ages, ca. 200–183 million years ago). It was described by Sir Richard Owen in 1854 from remains discovered in South Africa, and is thus one of the first dinosaurs to have been named. Fossils have since been found at other locations in South Africa, Lesotho, and Zimbabwe. Material from Arizona's Kayenta Formation, India, and Argentina has been assigned to the genus at various times, but the Arizonan and Argentinian material are now assigned to other genera. The type species is ''M. carinatus''; seven other species have been named during the past 150 years, but only ''M. kaalae'' is still considered valid. Early sauropodomorph systematics have undergone numerous revisions during the last several years, and many scientists disagree where exactly ''Massospondylus'' lies on the dinosaur evolutiona ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sauropodomorpha
Sauropodomorpha ( ; from Greek, meaning "lizard-footed forms") is an extinct clade of long-necked, herbivorous, saurischian dinosaurs that includes the sauropods and their ancestral relatives. Sauropods generally grew to very large sizes, had long necks and tails, were quadrupedal, and became the largest animals to ever walk the Earth. The '' prosauropods,'' which preceded the sauropods, were smaller and were often able to walk on two legs. The sauropodomorphs were the dominant terrestrial herbivores throughout much of the Mesozoic Era, from their origins in the Late Triassic (approximately 230 Ma) until their decline and extinction at the end of the Cretaceous. Description Sauropodomorphs were adapted to browsing higher than any other contemporary herbivore, giving them access to high tree foliage. This feeding strategy is supported by many of their defining characteristics, such as: a light, tiny skull on the end of a long neck (with ten or more elongated cervical verte ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Adeopapposaurus
''Adeopapposaurus'' (meaning "far eating lizard", in reference to its long neck) is a genus of prosauropod dinosaur from the Early Jurassic Cañón del Colorado Formation of San Juan, Argentina. It was similar to ''Massospondylus''. Four partial skeletons with two partial skulls are known. The type specimen, PVSJ568, includes a skull and most of a skeleton to just past the hips. The form of the bones at the tips of the upper and lower jaws suggests it had keratinous beaks. The fossils now named ''Adeopapposaurus'' were first thought to represent South American examples of ''Massospondylus''; while this is no longer the case, ''Adeopapposaurus'' is classified as a massospondylid. ''Adeopapposaurus'' was described in 2009 by Ricardo N. Martínez. The type species is ''A. mognai'', referring to the Mogna locality where it was found. Phylogeny The following cladogram shows the position of ''Adeopapposaurus'' within Massopoda, according to Oliver W. M. Rauhut and colleagues, 2 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quadratojugal Bone
The quadratojugal is a skull bone present in many vertebrates, including some living reptiles and amphibians. Anatomy and function In animals with a quadratojugal bone, it is typically found connected to the jugal (cheek) bone from the front and the squamosal bone from above. It is usually positioned at the rear lower corner of the cranium. Many modern tetrapods lack a quadratojugal bone as it has been lost or fused to other bones. Modern examples of tetrapods without a quadratojugal include salamanders, mammals, birds, and squamates (lizards and snakes). In tetrapods with a quadratojugal bone, it often forms a portion of the jaw joint. Developmentally, the quadratojugal bone is a dermal bone in the temporal series, forming the original braincase. The squamosal and quadratojugal bones together form the cheek region and may provide muscular attachments for facial muscles. In reptiles and amphibians In most modern reptiles and amphibians, the quadratojugal is a prominent, str ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quadrate Bone
The quadrate bone is a skull bone in most tetrapods, including amphibians, sauropsids (reptiles, birds), and early synapsids. In most tetrapods, the quadrate bone connects to the quadratojugal and squamosal bones in the skull, and forms upper part of the jaw joint. The lower jaw articulates at the articular bone, located at the rear end of the lower jaw. The quadrate bone forms the lower jaw articulation in all classes except mammals. Evolutionarily, it is derived from the hindmost part of the primitive cartilaginous upper jaw. Function in reptiles In certain extinct reptiles, the variation and stability of the morphology of the quadrate bone has helped paleontologists in the species-level taxonomy and identification of mosasaur squamates and spinosaurine dinosaurs. In some lizards and dinosaurs, the quadrate is articulated at both ends and movable. In snakes, the quadrate bone has become elongated and very mobile, and contributes greatly to their ability to swallow ve ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lacrimal Bone
The lacrimal bone is a small and fragile bone of the facial skeleton; it is roughly the size of the little fingernail. It is situated at the front part of the medial wall of the orbit. It has two surfaces and four borders. Several bony landmarks of the lacrimal bone function in the process of lacrimation or crying. Specifically, the lacrimal bone helps form the nasolacrimal canal necessary for tear translocation. A depression on the anterior inferior portion of the bone, the lacrimal fossa, houses the membranous lacrimal sac. Tears or lacrimal fluid, from the lacrimal glands, collect in this sac during excessive lacrimation. The fluid then flows through the nasolacrimal duct and into the nasopharynx. This drainage results in what is commonly referred to a runny nose during excessive crying or tear production. Injury or fracture of the lacrimal bone can result in posttraumatic obstruction of the lacrimal pathways. Structure Lateral or orbital surface The lateral or orbital surface i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plateosaurus
''Plateosaurus'' (probably meaning "broad lizard", often mistranslated as "flat lizard") is a genus of plateosaurid dinosaur that lived during the Late Triassic period, around 214 to 204 million years ago, in what is now Central and Northern Europe. ''Plateosaurus'' is a basal (early) sauropodomorph dinosaur, a so-called "prosauropod". The type species is ''Plateosaurus trossingensis''; before 2019, that honor was given to ''Plateosaurus engelhardti'', but it was ruled as undiagnostic (i.e. indistinguishable from other dinosaurs) by the ICZN. Currently, there are three valid species; in addition to ''P. trossingensis'', ''P. longiceps'' and ''P. gracilis'' are also known. However, others have been assigned in the past, and there is no broad consensus on the species taxonomy of plateosaurid dinosaurs. Similarly, there are a plethora of synonyms (invalid duplicate names) at the genus level. Discovered in 1834 by Johann Friedrich Engelhardt and described three years later by Herm ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Postorbital Bone
The ''postorbital'' is one of the bones in vertebrate skulls which forms a portion of the dermal skull roof and, sometimes, a ring about the orbit. Generally, it is located behind the postfrontal and posteriorly to the orbital fenestra. In some vertebrates, the postorbital is fused with the postfrontal to create a postorbitofrontal. Birds have a separate postorbital as an embryo An embryo is an initial stage of development of a multicellular organism. In organisms that reproduce sexually, embryonic development is the part of the life cycle that begins just after fertilization of the female egg cell by the male sperm ..., but the bone fuses with the frontal before it hatches. References * Roemer, A. S. 1956. ''Osteology of the Reptiles''. University of Chicago Press. 772 pp. Skull {{Vertebrate anatomy-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jugal Bone
The jugal is a skull bone found in most reptiles, amphibians and birds. In mammals, the jugal is often called the malar or zygomatic. It is connected to the quadratojugal and maxilla, as well as other bones, which may vary by species. Anatomy The jugal bone is located on either side of the skull in the circumorbital region. It is the origin of several masticatory muscles in the skull. The jugal and lacrimal bones are the only two remaining from the ancestral circumorbital series: the prefrontal, postfrontal, postorbital, jugal, and lacrimal bones. During development, the jugal bone originates from dermal bone. In dinosaurs This bone is considered key in the determination of general traits in cases in which the entire skull has not been found intact (for instance, as with dinosaurs in paleontology). In some dinosaur genera the jugal also forms part of the lower margin of either the antorbital fenestra or the infratemporal fenestra, or both. Most commonly, this bone art ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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