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Chelydridae
The Chelydridae is a family of turtles that has seven extinct and two extant genera. The extant genera are the snapping turtles, ''Chelydra'' and '' Macrochelys''. Both are endemic to the Western Hemisphere. The extinct genera are '' Acherontemys'', '' Chelydrops'', '' Chelydropsis'', '' Emarginachelys'', '' Macrocephalochelys'', '' Planiplastron'', and '' Protochelydra''. Fossil history The Chelydridae have a long fossil history, with extinct species reported from North America as well as all over Asia and Europe, far outside their present range. The earliest described chelydrid is '' Emarginachelys cretacea'', known from well-preserved fossils from the Maastrichtian stage of the Late Cretaceous of Montana. Another well-preserved fossil chelydrid is the Late Paleocene '' Protochelydra zangerli'' from North Dakota. The carapace of ''P. zangerli'' is higher-domed than that of the recent ''Chelydra'', a trait conjectured to be associated with the coexistence of large, turtle-eatin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Emarginachelys Cretacea
''Emarginachelys cretacea'' is a turtle belonging to the group Cryptodira, known from well preserved fossils from the Maastrichtian stage of the Late Cretaceous of Montana. Its exact phylogenetic position within Cryptodira is uncertain; different authors considered it to be either the earliest described chelydridae, chelydrid or a fossil relative of Kinosternoidea, kinosternoids. References Cryptodira Prehistoric turtle genera Late Cretaceous turtles of North America Hell Creek fauna Fossil taxa described in 1978 {{paleo-turtle-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Emarginachelys
''Emarginachelys cretacea'' is a turtle belonging to the group Cryptodira, known from well preserved fossils from the Maastrichtian stage of the Late Cretaceous of Montana Montana ( ) is a landlocked U.S. state, state in the Mountain states, Mountain West subregion of the Western United States. It is bordered by Idaho to the west, North Dakota to the east, South Dakota to the southeast, Wyoming to the south, an .... Its exact phylogenetic position within Cryptodira is uncertain; different authors considered it to be either the earliest described chelydrid or a fossil relative of kinosternoids. References Cryptodira Prehistoric turtle genera Late Cretaceous turtles of North America Hell Creek fauna Fossil taxa described in 1978 {{paleo-turtle-stub ... [...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] |
Western Hemisphere
The Western Hemisphere is the half of the planet Earth that lies west of the Prime Meridian (which crosses Greenwich, London, United Kingdom) and east of the 180th meridian.- The other half is called the Eastern Hemisphere. Geopolitically, the term Western Hemisphere is often used as a metonym for the Americas or the "New World", even though geographically the hemisphere also includes parts of other continents. Geography The Western Hemisphere consists of the Americas, excluding some of the Aleutian Islands to the southwest of the Alaskan mainland; the westernmost portions of Europe and Africa, both mainland and islands; the extreme eastern tip of the Russian mainland and islands ( North Asia); numerous territories in Oceania; and a large portion of Antarctica. The center of the Western Hemisphere is located in the Pacific Ocean at the intersection of the 90th meridian west and the Equator, among the Galápagos Islands. The nearest land is Genovesa Island at . The hi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eurasia
Eurasia ( , ) is a continental area on Earth, comprising all of Europe and Asia. According to some geographers, Physical geography, physiographically, Eurasia is a single supercontinent. The concept of Europe and Asia as distinct continents dates back to classical antiquity, antiquity, but their borders have historically been subject to change. For example, the ancient Greeks originally included Africa in Asia but classified Europe as separate land. Eurasia is connected to Africa at the Suez Canal, and the two are sometimes combined to describe the largest contiguous landmass on Earth, Afro-Eurasia. History Eurasia has been the host of many ancient civilizations, including those based in Mesopotamia, Egypt, the Indus Valley and China. In the Axial Age (mid-first millennium BCE), a continuous belt of civilizations stretched through the Eurasian Subtropics, subtropical zone from the Atlantic to the Pacific. This belt became the mainstream of world history for two millennia. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crocodilia
Crocodilia () is an order of semiaquatic, predatory reptiles that are known as crocodilians. They first appeared during the Late Cretaceous and are the closest living relatives of birds. Crocodilians are a type of crocodylomorph pseudosuchian, a subset of archosaurs that appeared about 235 million years ago and were the only survivors of the Triassic–Jurassic extinction event. While other crocodylomorph groups further survived the Cretaceous–Paleogene extinction event, notably sebecosuchians, only the crocodilians have survived into the Quaternary. The order includes the true crocodiles (family Crocodylidae), the alligators and caimans (family Alligatoridae), and the gharial and false gharial (family Gavialidae). Although the term "crocodiles" is sometimes used to refer to all of these families, the term "crocodilians" is less ambiguous. Extant crocodilians have flat heads with long snouts and tails that are compressed on the sides, with their eyes, ears, and n ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carapace
A carapace is a dorsal (upper) section of the exoskeleton or shell in a number of animal groups, including arthropods, such as crustaceans and arachnids, as well as vertebrates, such as turtles and tortoises. In turtles and tortoises, the underside is called the plastron. In botany, a carapace refers to the hard outer cover of a seed which protects the inner embryo. Crustaceans In crustaceans, the carapace functions as a protective cover over the cephalothorax (i.e., the fused head and thorax, as distinct from the abdomen behind). Where it projects forward beyond the eyes, this projection is called a rostrum. The carapace is calcified to varying degrees in different crustaceans. Zooplankton within the phylum Crustacea also have a carapace. These include Cladocera, ostracods, and isopods, but isopods only have a developed "cephalic shield" carapace covering the head. Arachnids In arachnids, the carapace is formed by the fusion of prosomal tergites into a single pl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
North Dakota
North Dakota ( ) is a U.S. state in the Upper Midwest, named after the indigenous Dakota people, Dakota and Sioux peoples. It is bordered by the Canadian provinces of Saskatchewan and Manitoba to the north and by the U.S. states of Minnesota to the east, South Dakota to the south, and Montana to the west. North Dakota is part of the Great Plains region, characterized by broad prairies, steppe, temperate savanna, badlands, and farmland. North Dakota is the List of U.S. states and territories by area, 19th-largest state by area, but with a population of just under 800,000, the List of U.S. states and territories by population, fourth-least populous and List of U.S. states by population density, fourth-least densely populated. The List of capitals in the United States, state capital is Bismarck, North Dakota, Bismarck and the List of cities in North Dakota, most populous city is Fargo, North Dakota, Fargo, which accounts for nearly a fifth of the state's population; both cities ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protochelydra Zangerli
''Protochelydra zangerli'' is an extinct species of chelydid in the extinct genus ''Protochelydra'' of Chelydridae The Chelydridae is a family of turtles that has seven extinct and two extant genera. The extant genera are the snapping turtles, ''Chelydra'' and '' Macrochelys''. Both are endemic to the Western Hemisphere. The extinct genera are '' Acherontemys .... References Chelydridae Extinct reptiles Paleogene reptiles of North America Eocene turtles Prehistoric turtle genera Fossil taxa described in 1973 Extinct turtles {{paleo-turtle-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paleocene
The Paleocene ( ), or Palaeocene, is a geological epoch (geology), epoch that lasted from about 66 to 56 mya (unit), million years ago (mya). It is the first epoch of the Paleogene Period (geology), Period in the modern Cenozoic Era (geology), Era. The name is a combination of the Ancient Greek ''palaiós'' meaning "old" and the Eocene Epoch (which succeeds the Paleocene), translating to "the old part of the Eocene". The epoch is bracketed by two major events in Earth's history. The K–Pg extinction event, brought on by an asteroid impact (Chicxulub impact) and possibly volcanism (Deccan Traps), marked the beginning of the Paleocene and killed off 75% of species, most famously the non-avian dinosaurs. The end of the epoch was marked by the Paleocene–Eocene Thermal Maximum (PETM), which was a major climatic event wherein about 2,500–4,500 gigatons of carbon were released into the atmosphere and ocean systems, causing a spike in global temperatures and ocean acidification. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Montana
Montana ( ) is a landlocked U.S. state, state in the Mountain states, Mountain West subregion of the Western United States. It is bordered by Idaho to the west, North Dakota to the east, South Dakota to the southeast, Wyoming to the south, and the Provinces and territories of Canada, Canadian provinces of Alberta, British Columbia, and Saskatchewan to the north. It is the List of U.S. states and territories by area, fourth-largest state by area, but the List of U.S. states and territories by population, eighth-least populous state and the List of U.S. states and territories by population density, third-least densely populated state. Its List of capitals in the United States, capital is Helena, Montana, Helena, while the List of municipalities in Montana, most populous city is Billings, Montana, Billings. The western half of the state contains numerous mountain ranges, while the eastern half is characterized by western prairie terrain and badlands, with smaller mountain ranges f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cretaceous
The Cretaceous ( ) is a geological period that lasted from about 143.1 to 66 mya (unit), million years ago (Mya). It is the third and final period of the Mesozoic Era (geology), Era, as well as the longest. At around 77.1 million years, it is the ninth and longest geological period of the entire Phanerozoic. The name is derived from the Latin , 'chalk', which is abundant in the latter half of the period. It is usually abbreviated K, for its German translation . The Cretaceous was a period with a relatively warm climate, resulting in high Sea level#Local and eustatic, eustatic sea levels that created numerous shallow Inland sea (geology), inland seas. These oceans and seas were populated with now-extinct marine reptiles, ammonites, and rudists, while dinosaurs continued to dominate on land. The world was largely ice-free, although there is some evidence of brief periods of glaciation during the cooler first half, and forests extended to the poles. Many of the dominant taxonomic gr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
