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Sahonachelyidae
Sahonachelyidae is an extinct family of pelomedusoid turtles from the Late Cretaceous (Maastrichtian) Maevarano Formation of Madagascar. The clade was recognized in 2021 by Joyce et al., and contains two genera: '' Sahonachelys'' and '' Sokatra''. The clade is characterized by the presence of a reduced contribution of the maxilla to the floor of the orbit, and, the presence of a distinct posterior process of the maxilla In vertebrates, the maxilla (: maxillae ) 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 maxil .... The clade went extinct at the end of the Cretaceous period during the K-Pg extinction event. References Pleurodira Late Cretaceous turtles Prehistoric turtles of Africa {{paleo-turtle-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sahonachelys
''Sahonachelys'' is an extinct genus of pelomedusoid turtle from the Late Cretaceous (Maastrichtian) Maevarano Formation of Madagascar. The genus contains a single species, ''Sahonachelys mailakavava''. Discovery and naming The holotype specimen, (UA) 10581 was originally discovered in June 2015 within a layer of the Maastrichtian aged Maevarano Formation within the Mahajanga Basin, north-western Madagascar, while removing overburden less than one meter above a layer rich in archosaur fossils. The holotype consists of a partial and well preserved skeleton consisting of the skull, a partial hyoid, a shell, and remains of the limbs, shoulder girdles and vertebrae. The taxon would later be erected as a new genus in 2021. The name Sahonachelys is a combination of the Malagasy words "sahona" meaning frog, and the Greek word "chelys" meaning turtle; the specific name is made up of Malagasy "mailaka" meaning quick and "vava" meaning mouth; the full binomial name translates to "quic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sokatra
''Sokatra'' is an extinct genus of pleurodiran turtle, known from the Cretaceous (Maastrichtian) Maevarano Formation of Madagascar. It belongs to the family Sahonachelyidae Sahonachelyidae is an extinct family of pelomedusoid turtles from the Late Cretaceous (Maastrichtian) Maevarano Formation of Madagascar. The clade was recognized in 2021 by Joyce et al., and contains two genera: '' Sahonachelys'' and '' Sokatr .... References {{Testudines Late Cretaceous turtles Pleurodira Prehistoric turtles of Africa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pleurodira
The Pleurodira are one of the two living suborders of turtles, the other being the Cryptodira. The division between these two suborders represents a very deep evolutionary divide between two very different types of turtles. The physical differences between them, although anatomical and largely internal, are nonetheless significant, and the zoogeographic implications of them are substantial. The Pleurodira are known more commonly as the side-necked turtles and the name Pleurodira quite literally translates to side neck, whereas the Cryptodira are known as hidden-necked turtles. The Pleurodira turtles are currently restricted to freshwater habitats in the Southern Hemisphere, largely to Australia, South America, and Africa. Within the Pleurodira, three living families are represented: Chelidae, also known as the Austro-South American side-necked turtles, the Pelomedusidae, also known as the African mud terrapins, and the Podocnemididae, also known as the American side-neck rive ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Maevarano Formation
The Maevarano Formation is a Late Cretaceous sedimentary formation (geology), rock formation found in the Mahajanga Province of northwestern Madagascar. It is most likely Maastrichtian in age, and records a seasonal, semiarid environment with rivers that had greatly varying discharge (hydrology), discharges. Notable animal fossils recovered include the theropod dinosaur ''Majungasaurus'', the early bird ''Vorona'', the paravian ''Rahonavis'', the titanosaurian sauropod ''Rapetosaurus'', and the giant frog ''Beelzebufo''. Description The Maevarano Formation is well exposed in the Mahajanga Basin, in particular near the village of Berivotra near the northwestern coast of the island where its outcrops have been heavily dissected by erosion. At the time it was being deposited, its latitude was between 30°S and 25°S as Madagascar drifted northward after splitting from India about 88 million years ago. It is composed of three smaller units or geologic unit, members. The lowest is the ... [...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] |
Maastrichtian
The Maastrichtian ( ) is, in the International Commission on Stratigraphy (ICS) geologic timescale, the latest age (geology), age (uppermost stage (stratigraphy), stage) of the Late Cretaceous epoch (geology), Epoch or Upper Cretaceous series (stratigraphy), Series, the Cretaceous geologic period, Period or system (stratigraphy), System, and of the Mesozoic geologic era, Era or Erathem. It spanned the interval from . The Maastrichtian was preceded by the Campanian and succeeded by the Danian (part of the Paleogene and Paleocene). It is named after the city of Maastricht, the capital and largest city of the Limburg (Netherlands), Limburg province in the Netherlands. The Cretaceous–Paleogene extinction event (formerly known as the Cretaceous–Tertiary period, Tertiary extinction event) occurred at the end of this age. In this extinction event, mass extinction, many commonly recognized groups such as non-avian dinosaurs, plesiosaurs and mosasaurs, as well as many other lesser-kn ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Madagascar
Madagascar, officially the Republic of Madagascar, is an island country that includes the island of Madagascar and numerous smaller peripheral islands. Lying off the southeastern coast of Africa, it is the world's List of islands by area, fourth largest island, the List of island countries, second-largest island country, and the List of countries and dependencies by area, 46th largest country overall. Its capital and List of cities in Madagascar, largest city is Antananarivo. Following the prehistoric breakup of the supercontinent Gondwana, Madagascar split from Africa during the Early Jurassic period, around 180 million years ago, and separated from the Indian subcontinent approximately 90 million years ago. This isolation allowed native plants and animals to evolve in relative seclusion; as a result, Madagascar is a biodiversity hotspot and one of the world's 17 megadiverse countries, with over 90% of its wildlife of Madagascar, wildlife being endemic. The island has ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Maxilla
In vertebrates, the maxilla (: maxillae ) 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. Anatomy Structure The maxilla is a paired bone - the two maxillae unite with each other at the intermaxillary suture. The maxilla consists of: * The body of the maxilla: pyramid-shaped; has an orbital, a nasal, an infratemporal, and a facial surface; contains the maxillary sinus. * Four processes: ** the zygomatic process ** the frontal process ** the alveolar process ** the palatine process It has three surfaces: * the anterior, posterior, medial Features of the maxilla include: * t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Orbit
In celestial mechanics, an orbit (also known as orbital revolution) is the curved trajectory of an object such as the trajectory of a planet around a star, or of a natural satellite around a planet, or of an artificial satellite around an object or position in space such as a planet, moon, asteroid, or Lagrange point. Normally, orbit refers to a regularly repeating trajectory, although it may also refer to a non-repeating trajectory. To a close approximation, planets and satellites follow elliptic orbits, with the center of mass being orbited at a focal point of the ellipse, as described by Kepler's laws of planetary motion. For most situations, orbital motion is adequately approximated by Newtonian mechanics, which explains gravity as a force obeying an inverse-square law. However, Albert Einstein's general theory of relativity, which accounts for gravity as due to curvature of spacetime, with orbits following geodesics, provides a more accurate calculation and u ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Posterior (anatomy)
Standard anatomical terms of location are used to describe unambiguously the anatomy of humans and other animals. The terms, typically derived from Latin or Greek language, Greek roots, describe something in its standard anatomical position. This position provides a definition of what is at the front ("anterior"), behind ("posterior") and so on. As part of defining and describing terms, the body is described through the use of anatomical planes and anatomical axes, axes. The meaning of terms that are used can change depending on whether a vertebrate is a biped or a quadruped, due to the difference in the neuraxis, or if an invertebrate is a non-bilaterian. A non-bilaterian has no anterior or posterior surface for example but can still have a descriptor used such as proximal or distal in relation to a body part that is nearest to, or furthest from its middle. International organisations have determined vocabularies that are often used as standards for subdisciplines of anatomy. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cretaceous–Paleogene Extinction Event
The Cretaceous–Paleogene (K–Pg) extinction event, also known as the K–T extinction, was the extinction event, mass extinction of three-quarters of the plant and animal species on Earth approximately 66 million years ago. The event caused the extinction of all non-avian dinosaurs. Most other tetrapods weighing more than also became extinct, with the exception of some ectothermic species such as sea turtles and crocodilians. It marked the end of the Cretaceous period, and with it the Mesozoic era, while heralding the beginning of the current era, the Cenozoic. In the geologic record, the K–Pg event is marked by a thin layer of sediment called the Cretaceous–Paleogene boundary, K–Pg boundary or K–T boundary, which can be found throughout the world in marine and terrestrial rocks. The boundary clay shows unusually high levels of the metal iridium, which is more common in asteroids than in the Earth's crust. As originally proposed in 1980 by a team of scientists le ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Late Cretaceous Turtles
Late or LATE may refer to: Everyday usage * Tardy, or late, not being on time * Late (or the late) may refer to a person who is dead Music * ''Late'' (The 77s album), 2000 * Late (Alvin Batiste album), 1993 * Late!, a pseudonym used by Dave Grohl on his '' Pocketwatch'' album * Late (rapper), an underground rapper from Wolverhampton * "Late", a song by Kanye West from ''Late Registration'' Other uses * Late (Tonga), an uninhabited volcanic island southwest of Vavau in the kingdom of Tonga * "Late" (''The Handmaid's Tale''), a television episode * LaTe, Oy Laivateollisuus Ab, a defunct shipbuilding company * Limbic-predominant age-related TDP-43 encephalopathy, a proposed form of dementia * Local-authority trading enterprise, a New Zealand business law * Local average treatment effect, a concept in econometrics * Late, a synonym for ''cooler'' in stellar classification See also * * * ''Lates'', a genus of fish in the lates perch family * Later (other) Later may refe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
