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Zoneait Nargorum
''Zoneait'' (pronounced "zone-eight" and meaning "large tooth" in the Kiowa language) is an extinct genus of thalattosuchian crocodylomorph known from a single species, ''Zoneait nargorum'', from the Middle Jurassic Snowshoe Formation of Oregon. Discovery and naming The holotype was collected by Lupher and Packard.Éric Buffetaut, Buffetaut. (1979). Jour.Paleontology. 53,pt.1: 210, tf.2f,g. ''Z. nargorum'' was named in 2015 by paleontologist Eric Wilberg on the basis of several partial skulls, vertebrae, and forelimb bones that were found in an outcrop of the Weberg Member of the Snowshoe Formation near the town of Izee, Oregon, Izee. It is a member of Metriorhynchoidea, a clade of marine-adapted thalattosuchians that existed until the Early Cretaceous. Description and classification The skeleton of ''Zoneait'' possesses several adaptations for offshore marine life but retains features characteristic of its land-living ancestors, indicating that it is a transitional form betw ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Middle Jurassic
The Middle Jurassic is the second Epoch (geology), epoch of the Jurassic Period (geology), Period. It lasted from about 174.1 to 161.5 million years ago. Fossils of land-dwelling animals, such as dinosaurs, from the Middle Jurassic are relatively rare, but geological formations containing land animal fossils include the Forest Marble Formation in England, the Kilmaluag Formation in Scotland,British Geological Survey. 2011Stratigraphic framework for the Middle Jurassic strata of Great Britain and the adjoining continental shelf: research report RR/11/06 British Geological Survey, Keyworth, Nottingham. the Calcaire de Caen of France, the Daohugou Beds in China, the Itat Formation in Russia, the Tiouraren Formation of Niger, and the Isalo III Formation of western Madagascar. Rocks of the Middle Jurassic were formerly (until about 1980s) in Europe called ''Dogger'' or ''Brown Jurassic''. Paleogeography During the Middle Jurassic Epoch, Pangaea began to separate into Laurasia and Gond ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Forearc Basin
A forearc is a region in a subduction zone between an oceanic trench and the associated volcanic arc. Forearc regions are present along convergent margins and eponymously form 'in front of' the volcanic arcs that are characteristic of convergent plate margins. A back-arc region is the companion region behind the volcanic arc. Many forearcs have an accretionary wedge which may form a topographic ridge known as an outer arc ridge that parallels the volcanic arc. A forearc basin between the accretionary wedge and the volcanic arc can accumulate thick deposits of sediment, sometimes referred to as an outer arc trough. Due to collisional stresses as one tectonic plate subducts under another, forearc regions are sources for powerful earthquakes. Formation During subduction, an oceanic plate is thrust below another tectonic plate, which can be oceanic or continental. Water and other volatiles in the subducting plate cause flux melting in the upper mantle, creating magma that rises and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thalattosuchia
Thalattosuchia is a clade of mostly marine crocodylomorphs from the Early Jurassic to the Early Cretaceous that had a cosmopolitan distribution. They are colloquially referred to as marine crocodiles or sea crocodiles, though they are not members of Crocodilia and records from Thailand and China suggest that some members lived in freshwater. The clade contains two major subgroupings, the Teleosauroidea and Metriorhynchoidea. Teleosauroids are not greatly specialised for oceanic life, with back osteoderms similar to other crocodyliformes. Within Metriorhynchoidea, the Metriorhynchidae displayed extreme adaptions for life in the open ocean, including the transformation of limbs into flippers, the development of a tail fluke, and smooth, scaleless skin, and probably gave Viviparity, live birth, seemingly uniquely among archosaurs. Taxonomy The term Thalattosuchia was coined by Fraas in 1901.Fraas E. 1901. Die Meerkrokodile (Thalattosuchia n. g.) eine neue Sauriergruppe der Juraform ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fossil Taxa Described In 2015
A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved in amber, hair, petrified wood and DNA remnants. The totality of fossils is known as the ''fossil record''. Though the fossil record is incomplete, numerous studies have demonstrated that there is enough information available to give a good understanding of the pattern of diversification of life on Earth. In addition, the record can predict and fill gaps such as the discovery of ''Tiktaalik'' in the arctic of Canada. Paleontology includes the study of fossils: their age, method of formation, and evolutionary significance. Specimens are sometimes considered to be fossils if they are over 10,000 years old. The oldest fossils are around 3.48 billion years to 4.1 billion years old. Early edition, published online before print. The ob ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Middle Jurassic Crocodylomorphs
Middle or The Middle may refer to: * Centre (geometry), the point equally distant from the outer limits. Places * Middle (sheading), a subdivision of the Isle of Man * Middle Bay (other) * Middle Brook (other) * Middle Creek (other) * Middle Island (other) * Middle Lake (other) * Middle Mountain, California * Middle Peninsula, Chesapeake Bay, Virginia * Middle Range, a former name of the Xueshan Range on Taiwan Island * Middle River (other) * Middle Rocks, two rocks at the eastern opening of the Straits of Singapore * Middle Sound, a bay in North Carolina * Middle Township (other) * Middle East Music * "Middle" (song), 2015 * "The Middle" (Jimmy Eat World song), 2001 * "The Middle" (Zedd, Maren Morris and Grey song), 2018 *"Middle", a song by Rocket from the Crypt from their 1995 album ''Scream, Dracula, Scream!'' *"The Middle", a song by Demi Lovato from their debut album ''Don't Forget'' *"The Middle", a song by Th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Prehistoric Marine Crocodylomorphs
Prehistory, also called pre-literary history, is the period of human history between the first known use of stone tools by hominins million years ago and the beginning of recorded history with the invention of writing systems. The use of symbols, marks, and images appears very early among humans, but the earliest known writing systems appeared years ago. It took thousands of years for writing systems to be widely adopted, with writing having spread to almost all cultures by the 19th century. The end of prehistory therefore came at different times in different places, and the term is less often used in discussing societies where prehistory ended relatively recently. It is based on an old conception of history that without written records there could be no history. The most common conception today is that history is based on evidence, however the concept of prehistory hasn't been completely discarded. In the early Bronze Age, Sumer in Mesopotamia, the Indus Valley Civilis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Monotypic Prehistoric Reptile Genera
In biology, a monotypic taxon is a taxonomic group (taxon) that contains only one immediately subordinate taxon. A monotypic species is one that does not include subspecies or smaller, infraspecific taxa. In the case of genera, the term "unispecific" or "monospecific" is sometimes preferred. In botanical nomenclature, a monotypic genus is a genus in the special case where a genus and a single species are simultaneously described. Theoretical implications Monotypic taxa present several important theoretical challenges in biological classification. One key issue is known as "Gregg's Paradox": if a single species is the only member of multiple hierarchical levels (for example, being the only species in its genus, which is the only genus in its family), then each level needs a distinct definition to maintain logical structure. Otherwise, the different taxonomic ranks become effectively identical, which creates problems for organizing biological diversity in a hierarchical system. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jurassic Animals Of North America
The Jurassic ( ) is a geologic period and stratigraphic system that spanned from the end of the Triassic Period million years ago (Mya) to the beginning of the Cretaceous Period, approximately 143.1 Mya. The Jurassic constitutes the second and middle period of the Mesozoic Era as well as the eighth period of the Phanerozoic Eon and is named after the Jura Mountains, where limestone strata from the period were first identified. The start of the Jurassic was marked by the major Triassic–Jurassic extinction event, associated with the eruption of the Central Atlantic Magmatic Province (CAMP). The beginning of the Toarcian Age started around 183 million years ago and is marked by the Toarcian Oceanic Anoxic Event, a global episode of oceanic anoxia, ocean acidification, and elevated global temperatures associated with extinctions, likely caused by the eruption of the Karoo-Ferrar large igneous provinces. The end of the Jurassic, however, has no clear, definitive boundary with the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Humerus
The humerus (; : humeri) is a long bone in the arm that runs from the shoulder to the elbow. It connects the scapula and the two bones of the lower arm, the radius (bone), radius and ulna, and consists of three sections. The humeral upper extremity of humerus, upper extremity consists of a rounded head, a narrow neck, and two short processes (tubercles, sometimes called tuberosities). The body of humerus, body is cylindrical in its upper portion, and more prism (geometry), prismatic below. The lower extremity of humerus, lower extremity consists of 2 epicondyles, 2 processes (trochlea of the humerus, trochlea and capitulum of the humerus, capitulum), and 3 fossae (radial fossa, coronoid fossa, and olecranon fossa). As well as its true anatomical neck, the constriction below the greater and lesser tubercles of the humerus is referred to as its Surgical neck of the humerus, surgical neck due to its tendency to fracture, thus often becoming the focus of surgeons. Etymology The word ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ulna
The ulna or ulnar bone (: ulnae or ulnas) is a long bone in the forearm stretching from the elbow to the wrist. It is on the same side of the forearm as the little finger, running parallel to the Radius (bone), radius, the forearm's other long bone. Longer and thinner than the radius, the ulna is considered to be the smaller long bone of the lower arm. The corresponding bone in the Human leg#Structure, lower leg is the fibula. Structure The ulna is a long bone found in the forearm that stretches from the elbow to the wrist, and when in standard anatomical position, is found on the Medial (anatomy), medial side of the forearm. It is broader close to the elbow, and narrows as it approaches the wrist. Close to the elbow, the ulna has a bony Process (anatomy), process, the olecranon process, a hook-like structure that fits into the olecranon fossa of the humerus. This prevents hyperextension and forms a hinge joint with the trochlea of the humerus. There is also a radial notch for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cricosaurus
''Cricosaurus'' is an extinct genus of marine crocodyliforms of the Late Jurassic. belonging to the family Metriorhynchidae. The genus was established by Johann Andreas Wagner in 1858 for three skulls from the Tithonian (Late Jurassic) of Germany. The name ''Cricosaurus'' means "Ring lizard", and is derived from the Greek '- ("ring") and -' ("lizard"). It was a relatively small reptile, with ''C. suevicus'' and ''C. araucanensis'' measuring and in total body length, respectively. Discovery ''Cricosaurus'' was first named by Wagner in 1858,Wagner A. 1858. Zur Kenntniss der Saurier aus den lithographischen Schiefern. ''Abhandlungen der Mathemat.-Physikalischen Classe der Königlich Bayerischen Akademie der Wissenschaften'' 8: 415-528. as a reclassification of a specimen he had previously described in 1852 ("Stenosaurus" ''elegans'', "Stenosaurus" being a misspelling of ''Steneosaurus'').Wagner A. 1852. Neu-aufgefundene Saurier-Überreste aus dem lithographischen Schiefern und ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metriorhynchus
''Metriorhynchus'' is an extinct genus of marine crocodyliform that lived in the oceans during the Late Jurassic. The type species, ''M. brevirostris'' was named in 1829 as a species of ''Steneosaurus'' before being named as a separate genus by the German palaeontologist Christian von Meyer in 1832. The name ''Metriorhynchus'' means "moderate snout", and is derived from the Greek ''Metrio''- ("moderate") and -''rhynchos'' ("snout"). Discovery and species Fossil specimens referrable to ''Metriorhynchus'' are known from Kimmeridgian (Late Jurassic) deposits of France. Valid species Only one valid species is recognized today, the type species ''M. geoffroyii'' (now called ''M. brevirostris''). ''"Metriorhynchus" hastifer'' and ''"M." palpebrosus'' are generically distinct from the ''Metriorhynchus'' type species, with ''hastifer'' being recovered as a geosaurine. Species in this genus were traditionally classed into two skull groups: longirostrine (long, narrow jaws) and brevirost ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
