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Nostoceras
''Nostoceras'' is an extinct genus of ammonites. The etymology of the name ''Nostoceras'' comes from "nostos" meaning return and "ceros" meaning horn, named as such by Alpheus Hyatt because it bends back on itself. Taxonomy ''Nostoceras'' is the type genus for the ammonite family Nostoceratidae which is included in the Turrilitoidea. The Turrilitoidea, with ''Nostoceras'' and the Nostoceratidae, are commonly included in the suborder Ancyloceratina but may instead belong in the Turrilitina, a proposed order of heteromorphs thought to have a separate derivation, though this separation does not have wide support. Fossil record Fossils of ''Nostoceras'' are found in marine strata from the Campanian stage of the Upper Cretaceous, in the USA, England, central Europe, west Africa, Australia and Madagascar (Angola, Australia, Austria, Belgium, Denmark, England, France, Germany, Iraq, Italy, Madagascar, the Netherlands, Nigeria, Oman, Spain, United States). Description Nostocer ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nostoceratidae
Nostoceratidae is a diverse family of heteromorph ammonites found throughout the oceans of the world during the Late Cretaceous. The nostoceratids are famous for the bizarre coiling of their shells. Many genera, such as '' Yezoceras'', '' Ainoceras'', '' Anaklinoceras'', and some species of ''Bostrychoceras'' and ''Eubostrychoceras'', display, as young shells at least, a helical coiling very similar to the shells of the related family, Turrilitidae. As adults, though, the coils then curve away from the axis of coiling, either as an oxbow-like curve around the juvenile coils as in ''Ainoceras'' and ''Anaklinoceras'', or in a simple curved loop beneath the juvenile coils, as in ''Yezoceras''. Other genera form loose coils, sometimes in a spiral, such as those of '' Madagascarites'', ''Muramotoceras'', '' Hyphantoceras'', and the infamously convolute ''Nipponites''. The ecology of nostoceratids is the subject of continued speculation, as the bizarrely coiled shells have no st ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ancyloceratina
The Ancyloceratina were a diverse suborder of ammonite most closely related to the ammonites of order Lytoceratina. They evolved during the Late Jurassic but were not very common until the Cretaceous period, when they rapidly diversified and became one of the most distinctive components of Cretaceous marine faunas. They have been recorded from every continent and many are used as zonal or index fossils. The most distinctive feature of the majority of the Ancyloceratina is the tendency for most of them to have shells that are not regular spirals like most other ammonites. These irregularly-coiled ammonites are called heteromorph ammonites, in contrast to regularly coiled ammonites, which are called homomorph ammonites. Biology The biology of the heteromorph ammonites is not clear, but one certainty is that their uncoiled shells would have made these forms very poor swimmers. Open shells, particularly ones with spines and ribs, create a lot of drag; but more importantly, the orie ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Campanian
The Campanian is the fifth of six ages of the Late Cretaceous Epoch on the geologic timescale of the International Commission on Stratigraphy (ICS). In chronostratigraphy, it is the fifth of six stages in the Upper Cretaceous Series. Campanian spans the time from 83.6 (± 0.2) to 72.1 (± 0.2) million years ago. It is preceded by the Santonian and it is followed by the Maastrichtian. The Campanian was an age when a worldwide sea level rise covered many coastal areas. The morphology of some of these areas has been preserved: it is an unconformity beneath a cover of marine sedimentary rocks. Etymology The Campanian was introduced in scientific literature by Henri Coquand in 1857. It is named after the French village of Champagne in the department of Charente-Maritime. The original type locality was a series of outcrop near the village of Aubeterre-sur-Dronne in the same region. Definition The base of the Campanian Stage is defined as a place in the stratigraphic colu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bostrychoceras
''Bostrychoceras'' is a genus of heteromorph ammonite from the family Nostoceratidae. Fossils have been found in Late Cretaceous sediments in Europe and North America North America is a continent in the Northern Hemisphere and almost entirely within the Western Hemisphere. It is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South America and th .... The shell of ''Bostrychoceras'' begins as a tightly wound helical spire, like that of '' Nostoceras'', from which hangs a U or J shaped body chamber, at least in the adult. The shell is covered with dense, strong, but un-flaired, ribs that are commonly sinuous and oblique. May nor may not have strong constrictions. Distribution Cretaceous of Nigeria, Peru, South Africa, Spain and the United States References ;Notes ;Bibliography * * ''Ammonoid Paleobiology'' (Topics in Geobiology) by Neil H. Landman, Kazushige Tanabe, and Richard Arnold Davis Ammonitida gene ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ammonite
Ammonoids are a group of extinct marine mollusc animals in the subclass Ammonoidea of the class Cephalopoda. These molluscs, commonly referred to as ammonites, are more closely related to living coleoids (i.e., octopuses, squid and cuttlefish) than they are to shelled nautiloids such as the living '' Nautilus'' species. The earliest ammonites appeared during the Devonian, with the last species vanishing during the Cretaceous–Paleogene extinction event. Ammonites are excellent index fossils, and linking the rock layer in which a particular species or genus is found to specific geologic time periods is often possible. Their fossil shells usually take the form of planispirals, although some helically spiraled and nonspiraled forms (known as heteromorphs) have been found. The name "ammonite", from which the scientific term is derived, was inspired by the spiral shape of their fossilized shells, which somewhat resemble tightly coiled rams' horns. Pliny the Elder ( 79 AD ne ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
United States
The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 states, a federal district, five major unincorporated territories, nine Minor Outlying Islands, and 326 Indian reservations. The United States is also in free association with three Pacific Island sovereign states: the Federated States of Micronesia, the Marshall Islands, and the Republic of Palau. It is the world's third-largest country by both land and total area. It shares land borders with Canada to its north and with Mexico to its south and has maritime borders with the Bahamas, Cuba, Russia, and other nations. With a population of over 333 million, it is the most populous country in the Americas and the third most populous in the world. The national capital of the United States is Washington, D.C. and its most populous city and principal financial center is New York City. Paleo-Americ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Netherlands
) , anthem = ( en, "William of Nassau") , image_map = , map_caption = , subdivision_type = Sovereign state , subdivision_name = Kingdom of the Netherlands , established_title = Before independence , established_date = Spanish Netherlands , established_title2 = Act of Abjuration , established_date2 = 26 July 1581 , established_title3 = Peace of Münster , established_date3 = 30 January 1648 , established_title4 = Kingdom established , established_date4 = 16 March 1815 , established_title5 = Liberation Day , established_date5 = 5 May 1945 , established_title6 = Kingdom Charter , established_date6 = 15 December 1954 , established_title7 = Caribbean reorganisation , established_date7 = 10 October 2010 , official_languages = Dutch , languages_type = Regional languages , languages_sub = yes , languages = , languages2_type = Recognised languages , languages2_sub = yes , languages2 = , demonym = Dutch , capital = Amsterdam , largest_city = capital , ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nigeria
Nigeria ( ), , ig, Naìjíríyà, yo, Nàìjíríà, pcm, Naijá , ff, Naajeeriya, kcg, Naijeriya officially the Federal Republic of Nigeria, is a country in West Africa. It is situated between the Sahel to the north and the Gulf of Guinea to the south in the Atlantic Ocean. It covers an area of , and with a population of over 225 million, it is the most populous country in Africa, and the world's sixth-most populous country. Nigeria borders Niger in the north, Chad in the northeast, Cameroon in the east, and Benin in the west. Nigeria is a federal republic comprising of 36 states and the Federal Capital Territory, where the capital, Abuja, is located. The largest city in Nigeria is Lagos, one of the largest metropolitan areas in the world and the second-largest in Africa. Nigeria has been home to several indigenous pre-colonial states and kingdoms since the second millennium BC, with the Nok civilization in the 15th century BC, marking the first ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oman
Oman ( ; ar, عُمَان ' ), officially the Sultanate of Oman ( ar, سلْطنةُ عُمان ), is an Arabian country located in southwestern Asia. It is situated on the southeastern coast of the Arabian Peninsula, and spans the mouth of the Persian Gulf. Oman shares land borders with Saudi Arabia, the United Arab Emirates, and Yemen, while sharing maritime borders with Iran and Pakistan. The coast is formed by the Arabian Sea on the southeast, and the Gulf of Oman on the northeast. The Madha and Musandam exclaves are surrounded by the United Arab Emirates on their land borders, with the Strait of Hormuz (which it shares with Iran) and the Gulf of Oman forming Musandam's coastal boundaries. Muscat is the nation's capital and largest city. From the 17th century, the Omani Sultanate was an empire, vying with the Portuguese and British empires for influence in the Persian Gulf and Indian Ocean. At its peak in the 19th century, Omani influence and control extended across ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spain
, image_flag = Bandera de España.svg , image_coat = Escudo de España (mazonado).svg , national_motto = ''Plus ultra'' (Latin)(English: "Further Beyond") , national_anthem = (English: "Royal March") , image_map = , map_caption = , image_map2 = , capital = Madrid , coordinates = , largest_city = Madrid , languages_type = Official language , languages = Spanish , ethnic_groups = , ethnic_groups_year = , ethnic_groups_ref = , religion = , religion_ref = , religion_year = 2020 , demonym = , government_type = Unitary parliamentary constitutional monarchy , leader_title1 = Monarch , leader_name1 = Felipe VI , leader_title2 = Prime Minister , leader_name2 = Pedro Sánchez , legislature = C ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ammonitida Genera
Ammonitida is an order of ammonoid cephalopods that lived from the Jurassic through Paleocene time periods, commonly with intricate ammonitic sutures. Ammonitida is divided into four suborders, the Phylloceratina, Lytoceratina, Ancyloceratina, and Ammonitina. The Phylloceratina is the ancestral stock, derived from the Ceratitida near the end of the Triassic. The Phylloceratina gave rise to the Lytoceratina near the beginning of the Jurassic which in turn gave rise to the highly specialized Ancyloceratina near the end of the Jurassic. Both the Phylloceratina and Lytoceratina gave rise to various stocks combined in the Ammonitina. These four suborders are further divided into different stocks, comprising various families combined into superfamilies. Some like the Hildoceratoidea and Stephanoceratoidea are restricted to the Jurassic. Others like the Hoplitoidea and Acanthoceratoidea Acanthoceratoidea, formerly Acanthocerataceae, is a superfamily of Upper Cretaceous ammonoi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phragmocone
The phragmocone is the chambered portion of the shell of a cephalopod. It is divided by septa into camerae. In most nautiloids and ammonoids, the phragmocone is a long, straight, curved, or coiled structure, in which the camarae are linked by a siphuncle which determines buoyancy by means of gas exchange. Despite this benefit, such a large shell adds to the mass of the animal, and hence is disadvantageous in catching fast-moving prey. Some nautiloids, such as the Silurian Ascocerida, dropped the phragmocone upon maturity, presumably to increase speed and maneuverability. They thus became the early Paleozoic equivalent of coleoids. The early coleoids and belemnoids adopted a different approach: the phragmocone was retained but became internal and reduced. In general the shell in cephalopods tends to be vestigial or absent. Fossil record Being the only biomineralised part of most cephalopods, the phragmocone is typically the only part to enter the fossil record. It is someti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
