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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 Exoskeleton, 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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ancyloceratoidea
Ancyloceratoidea, formerly Ancylocerataceae, is a superfamily of typically uncoiled and loosely coiled heteromorph Ammonoidea, ammonoids established by Alpheus Hyatt in 1900, that may contain as many as 11 families, depending on the classification accepted. Taxonomy The Taxonomy (biology), taxonomy content, or Family (biology), families, of the Ancycloceratoidea has grown over the year, partly with the addition of newly defined families and partly with the moving of families from other superfamilies. Arkell, ''et al.'' (1957) in the Treatise on Invertebrate Paleontology, Treatise Part L included just the Ancyloceratidae Meek 1876, Bochianitidae Spath 1922, Hemihoplitidae Spath 1924, and Heteroceratidae Hyatt 1900 within the Ancylocerataceae. The Crioceratitidae Wright 1952 was considered a subfamily, the Crioceratitinae, within the Ancycloceratidae, the other being the Ancyloceratinae. Families recognized in the Treatise and subsequently removed to the Ancycloceratoidea from ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ammonite Cemetery
Ammonoids are extinct, (typically) coiled-shelled cephalopods comprising the subclass Ammonoidea. They are more closely related to living octopuses, squid, and cuttlefish (which comprise the clade Coleoidea) than they are to nautiluses (family Nautilidae). The earliest ammonoids appeared during the Emsian stage of the Early Devonian (410.62 million years ago), with the last species vanishing during or soon after the Cretaceous–Paleogene extinction event (66 million years ago). They are often called ammonites, which is most frequently used for members of the order Ammonitida, the only remaining group of ammonoids from the Jurassic up until their extinction. Ammonoids exhibited considerable diversity over their evolutionary history, with over 10,000 species having been described. Ammonoids are excellent index fossils, and they have been frequently used to link rock layers in which a particular species or genus is found to specific geologic time periods. Their fossil shells usual ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Scaphitoidea
Scaphitidae is a family of extinct cephalopods belonging to the family of heteromorph ammonites (suborder Ancyloceratina). There is a possible fossil record of them being the last ammonites with fossils dating to the Danian of the Paleocene in Denmark, the Netherlands, the US and Turkmenistan. Genera Scaphitidae Gill, 1871 *Subfamily Otoscaphitinae Wright, 1953 **''Yezoites'' Yabe, 1910 *Subfamily Scaphitinae Gill, 1871 **''Acanthoscaphites'' Nowak, 1911 **''Clioscaphites'' Cobban, 1951 **''Discoscaphites'' Meek, 1870 **'' Eoscaphites'' Breistroffer, 1947 **''Hoploscaphites'' Nowak, 1911 **'' Indoscaphites'' Spath, 1953 **''Jeletzkytes'' Riccardi, 1983 **''Ponteixites'' Warren, 1934 **''Rhaeboceras'' Meek, 1876 **''Scaphites ''Scaphites'' is a genus of heteromorph ammonites belonging to the Scaphitidae family. They were a widespread genus that thrived during the Late Cretaceous period. Morphology ''Scaphites'' generally have a chambered, boat-shaped shell. The ini ...'' Pa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jurassic
The Jurassic ( ) is a Geological period, geologic period and System (stratigraphy), 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, Mesozoic Era as well as the eighth period of the Phanerozoic, 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, 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 Anoxic event, oceanic anoxia, ocean acidification, and elevated global temperatures associated with extinctions, likely caused by the eruption of the Kar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lytoceratina
Lytoceratina is a suborder of Jurassic and Cretaceous ammonites that produced loosely coiled, evolute and gyroconic shells in which the sutural element are said to have complex moss-like endings. Morphologic characteristics Shells are generally evolute, with all whorls exposed and touching, some are gyroconic with whorls separated by a space. Whorl sections vary from subcircular to narrowly compressed. The venter, or outer rim, is generally broadly arched but in some is keeled. Sides are either smooth or ribbed. Sutural elements are typically complex, referred to in the literature as moss-like, with adventious and secondary subdivisions. Saddle endings tend to be rounded but usually not phylloid, lobes tend to be more jagged with thornlike endings. Aptychi are single valved and concentrically striated (Anaptychus) Derivation and phylogeny The Lytoceratina, which constitute a suborder within the Ammonitida, are derived from the Triassic Ussuritidae or Discophyllitidae, familie ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Turrilitoidea
Turrilitoidea is a diverse superfamily of Cretaceous ammonites generally considered as heteromorphic and commonly included in the suborder Ancyloceratina. Shells of this diverse group do not coil planospirally, as typical for most ammonitida, ammonites, but rather take on a variety of unique forms. Separation of Turrilitoidea along with Ptychoceratoidea and Scaphatoidea into a different suborder, Turrilitina, was proposed by Beznosov and Mikhailova in 1983 however this view is not accepted by most authors. Some, such as the eponymous ''Turrilites'', coiled helically, like an auger shell, while others, such as ''Hamites (genus), Hamites'', had shells with long straight sections, while the one-of-a-kind ''Nipponites'' coiled in a way so as to appear as a ball of knots. As with other ammonites, the last of the Turrilitoidea had perished by the end of the Cretaceous during the Cretaceous–Paleogene extinction event. References * Arkell ''et al.'', 1957. Mesozoic Ammonoidea,' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paper Clip
A paper clip (or paperclip) is a tool used to hold sheets of paper together, usually made of steel wire bent to a looped shape (though some are covered in plastic). Most paper clips are variations of the ''Gem'' type introduced in the 1890s or earlier, characterized by the one and a half loops made by the wire. Common to paper clips proper is their utilization of torsion and elasticity in the wire, and friction between wire and paper. When a moderate number of sheets are inserted between the two "tongues" of the clip, the tongues will be forced apart and cause torsion in the bend of the wire to grip the sheets together. They are usually used to bind papers together for productivity and portability. The paper clip's widespread use in various settings, from offices to educational institutions, underscores its functional design and adaptability. While primarily designed for binding papers, its versatility has led to a range of applications, both practical and creative. Shape and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
South America
South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a considerably smaller portion in the Northern Hemisphere. It can also be described as the southern Subregion#Americas, subregion of the Americas. South America is bordered on the west by the Pacific Ocean, on the north and east by the Atlantic Ocean, and to the south by the Drake Passage; North America and the Caribbean Sea lie to the northwest. The continent includes twelve sovereign states: Argentina, Bolivia, Brazil, Chile, Colombia, Ecuador, Guyana, Paraguay, Peru, Suriname, Uruguay, and Venezuela; two dependent territory, dependent territories: the Falkland Islands and South Georgia and the South Sandwich Islands; and one administrative division, internal territory: French Guiana. The Dutch Caribbean ABC islands (Leeward Antilles), ABC islands (Aruba, Bonaire, and Curaçao) and Trinidad and Tobago are geologically located on the South-American continental shel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tropaeum
''Tropaeum'' is an extinct genus of ammonites found throughout the oceans of the world during the Early Cretaceous. As with many other members of the family Ancyloceratidae, there was a trend among species within this genus to uncoil somewhat, in a very similar manner to the genus ''Lytoceras''. The largest species, ''T. imperator'' of Australia, had a shell a little over one meter in diameter. The name "Tropaeum" was applied by paleontologist James De Carle Sowerby, in 1837. References External links * photograph of the holotype A holotype (Latin: ''holotypus'') is a single physical example (or illustration) of an organism used when the species (or lower-ranked taxon) was formally described. It is either the single such physical example (or illustration) or one of s ... of ''T. imperator' Ammonitida genera Early Cretaceous ammonites Ammonites of Australia Ancyloceratoidea {{Ammonite-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
