|
Megactenopetalus
''Megactenopetalus'' is an extinct genus of petalodont fish which lived from the late Early Permian through the Late Permian. It is known from a single species: ''M. kaibabanus''. It was one of the last and largest petalodonts; estimates place it at 1.6 meters or 5.2 feet in length with a 20 centimeter or 7 inch mouth. It is known from the southwest of the United States, the Middle East, and China. The holotype was an upper left dentary which came from the Kaibab Formation on the northern rim of the Grand Canyon. It is probably closely related to ''Ctenoptychius ''Ctenoptychius'' (meaning "comb-folded", from the Greek language, Greek wiktionary:cteno-, κτείς or ''kteís'' meaning "comb" and wiktionary:πτυχή#Ancient_Greek, πτυχή or ''ptychos'' meaning "fold") is an extinct genus of Chondric ...''.Ossian, C. (1976). Redescription of Megactenopetalus kaibabanus David 1944 (Chondrichthyes: Petalodontidae) with Comments on Its Geographic and Stratigraphic Distributio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Petalodontiformes
Petalodontiformes ("thin-plate teeth") is an extinct order of marine cartilaginous fish related to modern day chimaera found in what is now the United States of America and Europe.Lund, Richard, E. D. Grogan, and M. Fath. "On the relationships of the Petalodontiformes (Chondrichthyes)." Paleontological Journal 48.9 (2014): 1015-1029. Most species are known only from isolated teeth.Dalla Vecchia, Fabio Marco, and Museo Paleontologico Cittadino. "A new petalodont tooth (Chondrichthyes, Petalodontiformes) from the Lower Permian of the Carnic Alps (Friuli, NE Italy)." Bollettino della Società Paleontologica Italiana 39 (2000): 225-228. All fossils range from the Carboniferous to the Permian, where they are presumed to have died out during the Permian/Triassic extinction event. The two best known species are '' Belantsea montana'', from the Carboniferous Bear Gulch, Montana Montana ( ) is a landlocked U.S. state, state in the Mountain states, Mountain West subregion of the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kungurian
In the geologic timescale, the Kungurian is an age or stage of the Permian. It is the latest or upper of four subdivisions of the Cisuralian Epoch or Series. The Kungurian lasted between and million years ago (Ma). It was preceded by the Artinskian and followed by the Roadian. Stratigraphy The Kungurian is named after the Russian city of Kungur in Perm Krai. The stage was introduced into scientific literature by Russian geologist Alexandr Antonovich Stukenberg (Alexander Stuckenberg) in 1890.; 2002: ''Progress report on the base of the Artinskian and base of the Kungurian by the Cisuralian Working Group'', Permophiles 41: pp 13–16. The base of the Kungurian Stage is defined as the place in the stratigraphic record where fossils of conodont species '' Neostreptognathodus pnevi'' and ''Neostreptognathodus exculptus'' first appear. As of 2009, there was no agreement yet on a global reference profile (a GSSP) for the base of the Kungurian. The top of the Kungurian (the base of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wuchiapingian
In the geologic timescale, the Wuchiapingian or Wujiapingian (from in the Liangshan area of Hanzhong, Shaanxi Province ) is an age or stage of the Permian. It is also the lower or earlier of two subdivisions of the Lopingian Epoch or Series. The Wuchiapingian spans the time between and million years ago (Ma). It was preceded by the Capitanian and followed by the Changhsingian. Regional stages with which the Wuchiapingian is coeval or overlaps include the Djulfian or Dzhulfian, Longtanian, Rustlerian, Saladoan, and Castilian. Stratigraphic definitions The Wuchiapingian was first used in 1962, when the Lopingian Series of southwestern China was divided in the Changhsingian and Wuchiapingian Formations. In 1973 the Wuchiapingian was first used as a chronostratigraphic unit (i.e. a stage, as opposed to a formation, which is a lithostratigraphic unit). The base of the Wuchiapingian Stage is defined as the place in the stratigraphic record where the conodont specie ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
United States
The United States of America (USA), also known as the United States (U.S.) or America, is a country primarily located in North America. It is a federal republic of 50 U.S. state, states and a federal capital district, Washington, D.C. The 48 contiguous states border Canada to the north and Mexico to the south, with the semi-exclave of Alaska in the northwest and the archipelago of Hawaii in the Pacific Ocean. The United States asserts sovereignty over five Territories of the United States, major island territories and United States Minor Outlying Islands, various uninhabited islands in Oceania and the Caribbean. It is a megadiverse country, with the world's List of countries and dependencies by area, third-largest land area and List of countries and dependencies by population, third-largest population, exceeding 340 million. Its three Metropolitan statistical areas by population, largest metropolitan areas are New York metropolitan area, New York, Greater Los Angeles, Los Angel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Middle East
The Middle East (term originally coined in English language) is a geopolitical region encompassing the Arabian Peninsula, the Levant, Turkey, Egypt, Iran, and Iraq. The term came into widespread usage by the United Kingdom and western European nations in the early 20th century as a replacement of the term Near East (both were in contrast to the Far East). The term "Middle East" has led to some confusion over its changing definitions. Since the late 20th century, it has been criticized as being too Eurocentrism, Eurocentric. The region includes the vast majority of the territories included in the closely associated definition of West Asia, but without the South Caucasus. It also includes all of Egypt (not just the Sinai Peninsula, Sinai) and all of Turkey (including East Thrace). Most Middle Eastern countries (13 out of 18) are part of the Arab world. The list of Middle Eastern countries by population, most populous countries in the region are Egypt, Turkey, and Iran, whil ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
China
China, officially the People's Republic of China (PRC), is a country in East Asia. With population of China, a population exceeding 1.4 billion, it is the list of countries by population (United Nations), second-most populous country after India, representing 17.4% of the world population. China spans the equivalent of five time zones and Borders of China, borders fourteen countries by land across an area of nearly , making it the list of countries and dependencies by area, third-largest country by land area. The country is divided into 33 Province-level divisions of China, province-level divisions: 22 provinces of China, provinces, 5 autonomous regions of China, autonomous regions, 4 direct-administered municipalities of China, municipalities, and 2 semi-autonomous special administrative regions. Beijing is the country's capital, while Shanghai is List of cities in China by population, its most populous city by urban area and largest financial center. Considered one of six ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kaibab Limestone
The Kaibab Limestone is a resistant cliff-forming, Permian geologic formation that crops out across the U.S. states of northern Arizona, southern Utah, east central Nevada and southeast California. It is also known as the Kaibab Formation in Arizona, Nevada, and Utah. The Kaibab Limestone forms the rim of the Grand Canyon. In the Big Maria Mountains, California, the Kaibab Limestone is highly metamorphosed and known as the Kaibab Marble. Nomenclature The Kaibab Limestone was named by Darton in 1910 for the Kaibab Plateau, which is on the north side of Grand Canyon in Coconino County, Arizona. In his definition of the Kaibab Limestone, no type locality was designated. He also designated the Kaibab Limestone as the upper formation of the Aubrey Group, a now-abandoned stratigraphic unit. In 1921, Bassler and Reeside revised Darton's work and defined the ''Harrisburg gypsiferous member'' of the Kaibab Limestone.Bassler, H., and J. B. Reeside, Jr., 1921, ''Oil prospects in Washi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Grand Canyon
The Grand Canyon is a steep-sided canyon carved by the Colorado River in Arizona, United States. The Grand Canyon is long, up to wide and attains a depth of over a mile (). The canyon and adjacent rim are contained within Grand Canyon National Park, the Kaibab National Forest, Grand Canyon–Parashant National Monument, the Hualapai, Hualapai Indian Reservation, the Havasupai Indian Reservation and the Navajo Nation. President Theodore Roosevelt was a major proponent of the preservation of the Grand Canyon area and visited it on numerous occasions to hunt and enjoy the scenery. Nearly two billion years of Earth's geological history have been exposed as the Colorado River and its tributaries cut their Stream channel, channels through layer after layer of rock while the Colorado Plateau was Tectonic uplift, uplifted. [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ctenoptychius
''Ctenoptychius'' (meaning "comb-folded", from the Greek language, Greek wiktionary:cteno-, κτείς or ''kteís'' meaning "comb" and wiktionary:πτυχή#Ancient_Greek, πτυχή or ''ptychos'' meaning "fold") is an extinct genus of Chondrichthyes, cartilaginous fish in the order Petalodontiformes. While ''Ctenoptychius'' was historically thought to encompass a large number of species with Serration, serrated Crown (tooth), tooth crowns, it is now considered to include only the type species, ''C. apicalis''. This species lived during the Pennsylvanian (geology), Late Carboniferous period, and its fossils are known from the United Kingdom and potentially the United States. ''C. apicalis'' is known primarily from teeth, which have a flattened shape and serrated edges, although poorly-preserved specimens preserving the head, pectoral fins and Fish scale, scales of the body are also known. Based on this, it is believed that ''Ctenoptychius'' had a flattened, Batomorphi, ray-like b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Permian Cartilaginous Fish
The Permian ( ) is a geologic period and stratigraphic system which spans 47 million years, from the end of the Carboniferous Period million years ago (Mya), to the beginning of the Triassic Period 251.902 Mya. It is the sixth and last period of the Paleozoic Era; the following Triassic Period belongs to the Mesozoic Era. The concept of the Permian was introduced in 1841 by geologist Sir Roderick Murchison, who named it after the region of Perm in Russia. The Permian witnessed the diversification of the two groups of amniotes, the synapsids and the sauropsids (reptiles). The world at the time was dominated by the supercontinent Pangaea, which had formed due to the collision of Euramerica and Gondwana during the Carboniferous. Pangaea was surrounded by the superocean Panthalassa. The Carboniferous rainforest collapse left behind vast regions of desert within the continental interior. Amniotes, which could better cope with these drier conditions, rose to dominance in place of th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
