Arkanites
''Arkanites'' is a goniatitid ammonite that lived during the Early Pennsylvanian that has been found in Arkansas and Oklahoma in the U.S. Morphology The shell of ''Arkanites'' is subglobose, rather evolute, with a moderately wide umbilicus and a broadly rounded venter (or rim). Sculpture consists of well developed umbilical ribbing, sometimes with nodelike bases, and broad, deep, ventrolateral grooves. The ventral lobe of the suture, which sits on the outer rim, is large, with a median saddle that exceeds half its overall height. The first lateral saddle is broadly rounded, the adventitious lobe is large and pointed. Taxonomy ''Arkanites'' is possibly derived from '' Retites'' and closely related to '' Quinnites'', all which come from the Lower Pennsylvanian (Morrowan The Bashkirian is in the International Commission on Stratigraphy, ICS geologic timescale the lowest stage (stratigraphy), stage or oldest age (geology), age of the Pennsylvanian (geology), Pennsylvanian. Th ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Reticuloceratidae
Reticuloceratidae is one of five families of the Gastrioceratoidea superfamily. They are an extinct group of ammonoid, which are shelled cephalopods related to squids, belemnites, octopuses, and cuttlefish, and more distantly to the nautiloids. Taxonomy Family consists of 2 valid subfamilies: *Reticuloceratidae :* Reticuloceratinae ::*'' Agastrioceras'' ::*'' Alurites'' ::*''Aphantites ''Aphantites'' is a Lower Pennsylvanian 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 li ...'' ::*'' Arkanites'' ::*'' Bilinguites'' ::*'' Phillipsoceras'' ::*'' Quinnites'' ::*'' Reticuloceras'' ::*'' Retites'' ::*'' Tectiretites'' :* Surenitinae ::*'' Gaitherites'' ::*'' Marianoceras'' ::*'' Melvilloceras'' ::*'' Surenites'' ::*'' Ugamites'' ::*'' Verneuilites'' References The Paleobiology Databaseaccessed on 10/01/07 Goniatitida ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Pennsylvanian (geology)
The Pennsylvanian ( , also known as Upper Carboniferous or Late Carboniferous) is, in the International Commission on Stratigraphy, ICS geologic timescale, the younger of two period (geology), subperiods (or upper of two system (stratigraphy), subsystems) of the Carboniferous Period. It lasted from roughly . As with most other geochronology, geochronologic units, the stratum, rock beds that define the Pennsylvanian are well identified, but the exact date of the start and end are uncertain by a few hundred thousand years. The Pennsylvanian is named after the U.S. state of Pennsylvania, where the coal-productive beds of this age are widespread. The division between Pennsylvanian and Mississippian (geology), Mississippian comes from North American stratigraphy. In North America, where the early Carboniferous beds are primarily marine limestones, the Pennsylvanian was in the past treated as a full-fledged geologic period between the Mississippian and the Permian. In parts of Europe, ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Goniatitida
Goniatids, informally goniatites, are Ammonoidea, 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 Permian–Triassic extinction event, 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 Ammonitida, ammonites, being free swimming and possessing a head with two well developed eyes and arms (or tentacles). G ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Ammonoidea
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 nea ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Quinnites
''Quinnites'' is a genus of goniatitid ammonites included in the gastrioceratoidean family Reticuloceratidae known from the Carboniferous The Carboniferous ( ) is a geologic period and system of the Paleozoic that spans 60 million years from the end of the Devonian Period million years ago ( Mya), to the beginning of the Permian Period, million years ago. The name ''Carbonifero ... of the state of Arkansas, USA. Description ''Quinnites ''can be recognized by its thickly discoidal shell with a wide umbilicus and double pronged ventral lobe with a median saddle about half as high as the entire lobe. Umbilical ribs are common. May have spiral ornamentation, constrictions, or ventral groove. Taxonomy ''Quinnites'', named by Manger and Saunders 1980, contains two species, ''Quinnites henbesti'' and ''Quinnites textum'', both removed from Gastrioceras ( Branneroceras). References Goniatitida genera Reticuloceratidae Carboniferous ammonites of North America { ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Morrowan
The Bashkirian is in the International Commission on Stratigraphy, ICS geologic timescale the lowest stage (stratigraphy), stage or oldest age (geology), age of the Pennsylvanian (geology), Pennsylvanian. The Bashkirian age lasted from to Mega annum, Ma, is preceded by the Serpukhovian and is followed by the Moscovian (Carboniferous), Moscovian. The Bashkirian overlaps with the upper part of the Namurian and lower part of the Westphalian (stage), Westphalian stages from regional European stratigraphy. It also overlaps with the North American Morrowan and Atokan stages and the Chinese Luosuan and lower Huashibanian stages. Name and definition The Bashkirian was named after Bashkiria, the then Russian name of the republic of Bashkortostan in the southern Ural Mountains of Russia, home of the Bashkir people. The stage was introduced by Russian stratigrapher Sofia Viktorovna Semikhartova, Sofia Semikhatova in 1934. The base of the Bashkirian is at the first appearance of conodont ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Pennsylvanian Ammonites
Pennsylvanian may refer to: * A person or thing from Pennsylvania * Pennsylvanian (geology) The Pennsylvanian ( , also known as Upper Carboniferous or Late Carboniferous) is, in the International Commission on Stratigraphy, ICS geologic timescale, the younger of two period (geology), subperiods (or upper of two system (stratigraphy), s ..., a geological subperiod of the Carboniferous Period * ''Pennsylvanian'' (train), an Amtrak train {{disambiguation ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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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]   |