|
Karagandoceras
''Karagandoceras'' is an ammonoid genus belonging to the goniatid family Karagandoceratidae that lived during the early Mississippian (lower Carboniferous The Carboniferous ( ) is a Geologic time scale, geologic period and System (stratigraphy), system of the Paleozoic era (geology), era that spans 60 million years, from the end of the Devonian Period Ma (million years ago) to the beginning of the ...). ''Karagandoceras'' has an involute, lenticular shell, with an acute ventral margin. The ventral lobe of the suture is wide with subparallel to divergent sides, divided by a median saddle with a relatively wide median lobe. Karagandoceratids, which include ''Karagandoceras'' and '' Mesonoceras'' are a rare offshoot of the Prionorceratinae that differ from their parent group by possession of an acute ventral margin and an increasingly trifid ventral lobe. References Paleobiology database-''Karagandoceras''8/22/10 8/22/10 * ''Masonoceras'', a new Karaganoceratid Ammonoid fro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Karagandocerataceae
Karagandoceratoidea is an Early Carboniferous (Mississippian) superfamily within the ammonoid order, Goniatitida, said to contain the Karagandoceratidae and Prodromitidae. Analysis Shells are discoidal to lenticular. Adult stages are oxygonic, having acute venters, or have distinct keels. The ventral lobe may be either bifurcate or trifurcate (two or three pronged) and there is a tendency to increase the number of elements ontogenetically in the suture. Taxonomic affinities In the most recent classifications, W.M. Furnish, et al., 2009 and GONIAT theKaraganoceratoidea, is divided into the families Karagandoceratidae and Prodromitidae, with '' Karagandoceras'', ''Bartzschiceras'' and ''Masonoceras'' included in the Karagandocertidae. Previously, Deiter Korn (2006) included ''Karagandoceras'' along with ''Bartzschiceras'' and ''Masonoceras'' in the subfamily Karagandoceratinae which he included in the Prionoceratidae as part of the Prionocerataceae. Note retention of the� ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Karagandoceratidae
The Karagondoceratidae is a small family of tornoceratin Goniatitida from the Lower Carboniferous (early Mississippian) which typifies the Karagandoceratoidea, in which it is included. Karagandoceratids are characterized by discoidal to lenticular shells that are oxyconic or keeled in the adult and in which the ventral lobe of the suture is ontogenetically subdivided, either trifurcated or bifurcated. The known genera are ''Bartzschiceras'', ''Karagandoceras'', and ''Masonoceras'', and possibly ''Voehringerites'' References taxonomy GONIAT-onlinePaleobiology Database - Karagandoceratidae Goniatitida families Karagandocerataceae {{Goniatitida-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mississippian Age
The Mississippian ( ), also known as Lower Carboniferous or Early Carboniferous, is a subperiod in the geologic timescale or a subsystem of the geologic record. It is the earlier of two subperiods of the Carboniferous period lasting from roughly 358.9 to 323.2 million years ago. As with most other geochronologic units, the rock beds that define the Mississippian are well identified, but the exact start and end dates are uncertain by a few million years. The Mississippian is so named because rocks with this age are exposed in the Mississippi Valley. The Mississippian was a period of marine transgression in the Northern Hemisphere: the sea level was so high that only the Fennoscandian Shield and the Laurentian Shield were dry land. The cratons were surrounded by extensive delta systems and lagoons, and carbonate sedimentation on the surrounding continental platforms, covered by shallow seas. In North America, where the interval consists primarily of marine limestones, it ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ammonoidea
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 scale, geologic time periods. Their ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Goniatitida
Goniatids, informally goniatites, are ammonoid cephalopods that form the order Goniatitida, derived from the more primitive Agoniatitida during the Middle Devonian some 390 million years ago (around Eifelian stage). Goniatites (goniatitids) survived the Late Devonian extinction to flourish during the Carboniferous and Permian only to become extinct at the end of the Permian some 139 million years later. Morphology All goniatites possessed an external shell, which is divided internally into chambers filled with gas giving it buoyancy during the life of the animal. An open chamber at the front of the shell provided living space for the goniatitid animal, with access to open water through a ventral siphuncle. The general morphology and habit of goniatites was probably similar to that of their later relatives the ammonites, being free swimming and possessing a head with two well developed eyes and arms (or tentacles). Goniatite shells are small to medium in size, almost alway ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carboniferous
The Carboniferous ( ) is a Geologic time scale, geologic period and System (stratigraphy), system of the Paleozoic era (geology), era that spans 60 million years, from the end of the Devonian Period Ma (million years ago) to the beginning of the Permian Period, Ma. It is the fifth and penultimate period of the Paleozoic era and the fifth period of the Phanerozoic eon (geology), eon. In North America, the Carboniferous is often treated as two separate geological periods, the earlier Mississippian (geology), Mississippian and the later Pennsylvanian (geology), Pennsylvanian. The name ''Carboniferous'' means "coal-bearing", from the Latin ("coal") and ("bear, carry"), and refers to the many coal beds formed globally during that time. The first of the modern "system" names, it was coined by geologists William Conybeare (geologist), William Conybeare and William Phillips (geologist), William Phillips in 1822, based on a study of the British rock succession. Carboniferous is the per ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Goniatitida Genera
Goniatids, informally goniatites, are ammonoid cephalopods that form the order Goniatitida, derived from the more primitive Agoniatitida during the Middle Devonian some 390 million years ago (around Eifelian stage). Goniatites (goniatitids) survived the Late Devonian extinction to flourish during the Carboniferous and Permian only to become extinct at the end of the Permian some 139 million years later. Morphology All goniatites possessed an external shell, which is divided internally into chambers filled with gas giving it buoyancy during the life of the animal. An open chamber at the front of the shell provided living space for the goniatitid animal, with access to open water through a ventral siphuncle. The general morphology and habit of goniatites was probably similar to that of their later relatives the ammonites, being free swimming and possessing a head with two well developed eyes and arms (or tentacles). Goniatite shells are small to medium in size, almost always l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
