Xiphogymnites

	Xiphogymnites ''Xiphogymnites'' is an extinct ammonoid cephalopod genus from the Triassic included in the family Gymnitidae. It is known from the Balkans in eastern Europe. The shell is similar to that of ''Gymnites'', smooth, evolute, whorl section oval, venter arched, suture ammonitic, except that it has a row of tubercles on the venter followed by constrictions. Both genera are included in the Pinacoceratoidea Pinacoceratoidea, formerly Pinacocerataceae, are generally smooth, compressed, evolute to involute ammonoids from the Triassic, belonging to the Ceratitida, in which the suture is ammonitic, with adventitious and auxiliary elements. As presently .... References * Arkell, et al., Mesozoic Ammonoidea, ''Treatise on Invertebrate Paleontology'' Part L (1957) Geological Society of America. * E. T. Tozer. 1981. Triassic Ammonoidea: Classification, evolution and relationship with Permian and Jurassic Forms. The Ammonoidea: The evolution classification, mode of life and geological useful ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
	Gymnitidae Gymnitidae is a family of Lower to Middle Triassic ammonite cephalopods with evolute, discoidal shells. Hyatt and Smith (1905, p. 114-115) included the Gymnitidae in the suborder Ceratitoidea, which later became the superfamily Ceratitaceae and included in it genera more primitive than ''Gymnites'' as well as the more advanced ''Gymnites''. Those being '' Xenaspis'', '' Flemingites'', and ''Ophiceras''. Derivation as shown in Smith (1932 p. 30) is from ''Xenodiscus''. The more primitive ''Xenaspis'', ''Flemingites'', and ''Ophiceras'', found in Lower Triassic beds in western America have ceratitic sutures. The more developed ''Gymnites'' has deeply digitate ammonitic sutures. Arkell, et al., 1957, in the Treatise on Invertebrate Paleontology, on the other hand included the Gymnitidae in the Pinacocerataceae as the earlier and more primitive of its two families, combining ''Gymnites'' with coeval and more advanced forms. Genera included in the Gymnitidae sensu Arkell ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
picture info	Triassic The Triassic ( ) is a geologic period and system which spans 50.6 million years from the end of the Permian Period 251.902 million years ago ( Mya), to the beginning of the Jurassic Period 201.36 Mya. The Triassic is the first and shortest period of the Mesozoic Era. Both the start and end of the period are marked by major extinction events. The Triassic Period is subdivided into three epochs: Early Triassic, Middle Triassic and Late Triassic. The Triassic began in the wake of the Permian–Triassic extinction event, which left the Earth's biosphere impoverished; it was well into the middle of the Triassic before life recovered its former diversity. Three categories of organisms can be distinguished in the Triassic record: survivors from the extinction event, new groups that flourished briefly, and other new groups that went on to dominate the Mesozoic Era. Reptiles, especially archosaurs, were the chief terrestrial vertebrates during this time. A specialized subgroup of archo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
	Gymnites ''Gymnites'' is a genus of ammonoid cephalopod from the Middle Triassic belonging to the ceratitid family Gymnitidae. These nektonic carnivores lived during the Triassic period, Anisian age.Sepkoski, JacSepkoski's Online Genus Database – Cephalopoda/ref> Species * ''Gymnites aghdarbandensis'' Krystyn and Tatzreiter 1991 * ''Gymnites asseretoi'' Tozer 1972 * ''Gymnites billingsi'' Bucher 1989 * ''Gymnites calli'' Smith 1914 * ''Gymnites compressus'' Tozer 1994 * ''Gymnites evolutus'' Shevyrev 1995 * ''Gymnites humboldti Mojsisovics 1882 * ''Gymnites incultus'' Beyrich 1867 * ''Gymnites machangpingensis'' Zhao and Wang 1974 * ''Gymnites perplanus'' Meek 1877 * ''Gymnites petilus'' Wang and Chen 1979 * ''Gymnites procerus'' Tozer 1994 * ''Gymnites robinsoni'' Shevyrev 1995 * ''Gymnites toulai'' Arthaber 1914 * ''Gymnites tozeri'' Bucher 1992 * ''Gymnites tregorum'' Silberling and Nichols 1982 * ''Gymnites vastesellatus'' Welter 1915 Description The shell of ''Gymnites'' is evolut ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
	Pinacoceratoidea Pinacoceratoidea, formerly Pinacocerataceae, are generally smooth, compressed, evolute to involute ammonoids from the Triassic, belonging to the Ceratitida, in which the suture is ammonitic, with adventitious and auxiliary elements. As presently conceived, the Pinacoceratoidea, named by Mojsisovics, 1879, combines six families; the: * Pinacoceratidae * Carnitidae Gymnitidae Isculitidae * Klamathitidae * Sagenitidae In ''Treatise on Invertebrate Paleontology'', Part L, the superfamily included only the Pinacoceratidae and Gymnitidae. Of the families more newly included in the Pinacocerataceae, the Carnitidae was removed from the Ceratitaceae and the Isculitidae from the Ptychitaceae. ''Klamathites'' was removed from the Carnitidae as type for the Klamathitidae. The Sagenitidae is based on the subfamily Sagenitinae of the tropitacean family Haloritidae The Haloritidae is a family of subglobular, involute, Triassic ammonoids belonging to the ceratitid superfamily Tropitoidea. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
	Ceratitida Genera Ceratitida is an order that contains almost all ammonoid cephalopod genera from the Triassic as well as ancestral forms from the Upper Permian, the exception being the phylloceratids which gave rise to the great diversity of post Triassic ammonites. Ceratitids overwhelmingly produced planospirally coiled discoidal shells that may be evolute with inner whorls exposed or involute with only the outer whorl showing. In a few later forms the shell became subglobular, in others, trochoidal or uncoiled. Sutures are typically ceratitic, with smooth saddles and serrate or digitized lobes. In a few the sutures are goniatitic while in others they are ammonitic. Taxonomy * Ceratitida Ceratitoidea Choristoceratoidea Clydonitoidea Danubitoidea Dinaritoidea Lobitoidea Meekoceratoidea Megaphyllitoidea Nathorstitoidea Noritoidea Otoceratoidea Pinacoceratoidea Ptychitoidea Sageceratoidea Tropitoidea Xenodiscoidea Only eight superfamilies are shown i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
picture info	Triassic Ammonites The Triassic ( ) is a geologic period and system which spans 50.6 million years from the end of the Permian Period 251.902 million years ago ( Mya), to the beginning of the Jurassic Period 201.36 Mya. The Triassic is the first and shortest period of the Mesozoic Era. Both the start and end of the period are marked by major extinction events. The Triassic Period is subdivided into three epochs: Early Triassic, Middle Triassic and Late Triassic. The Triassic began in the wake of the Permian–Triassic extinction event, which left the Earth's biosphere impoverished; it was well into the middle of the Triassic before life recovered its former diversity. Three categories of organisms can be distinguished in the Triassic record: survivors from the extinction event, new groups that flourished briefly, and other new groups that went on to dominate the Mesozoic Era. Reptiles, especially archosaurs, were the chief terrestrial vertebrates during this time. A specialized subgroup of archosaurs ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]