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Aristoceratoides
''Aristoceratoides'' is an extinct ammonoid genus belonging to the goniatitid family Thalassoceratidae that lived during the Middle Permian. Named by Ruzhentsev, 1960, the type species is ''"Thalassoceras" varicosum'' Gemmellaro, 1887. The shell of ''Aristoceratoides'' is globose, with ventrolateral furrows; whorls wider than high. The suture is simpler than that of its likely ancestor ''Aristoceras ''Aristoceras'' is a Late Paleozoic goniatitid genus included in the Goniatitina suborder in which the lobes of the external suture are irregularly serrate. ''Aristoceras'', named by Ruzencev, 1950, may be a synonym for '' Euthalassoceras'' Mil ...''. Suture elements are simply digitate with digits restricted to the lower half of lobes. References * ''Aristoceratoides'' iGONIAT Online6/5/12 * W. B. Saunders, D. M. Work, and S. V. Nikolaeva, 1999. Evolution of Complexity in Paleozoic Ammonoid Sutures, Supplementary Material. Science Magazine * Fossils of Italy Goniati ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thalassoceratidae
Thalassoceratidae a family of late Paleozoic ammonites included in the goniatitid superfamily Thalassoceratoidea along with the Bisatoceratidae. Some eight genera are included, although the specific number and exactly which depends on the particular classification. Thalassoceratids are characterized by thick-discoidal to subglobular, involute shells with narrow or closed umbilici and serrate or digitate external lobes in the suture. This latter distinguishes them from the Bisatoceratidae in which the external lobes are smooth. The ventral lobe is extremely wide; the height of median saddle may exceed half the height of the entire ventral lobe itself. Some forms have ventrolateral grooves but spiral ornamentation is absent. Miller, Funish, and Schindewolf, 1957, in the Treatise on Invertebrate Paleontology The ''Treatise on Invertebrate Paleontology'' (or ''TIP'') published by the Geological Society of America and the University of Kansas Press, is a definitive multi-au ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wordian
In the geologic timescale, the Wordian is an age or stage of the Permian. It is the middle of three subdivisions of the Guadalupian Epoch or Series. The Wordian lasted between and million years ago (Ma). It was preceded by the Roadian and followed by the Capitanian. Stratigraphy The Wordian Stage was introduced into scientific literature by Johan August Udden in 1916 and was named after the Word Formation of the North American Permian Basin. The Wordian was first used as a stratigraphic subdivision of the Guadalupian in 1961, when both names were still only used regionally in the southern US. The stage was added to the internationally used ISC timescale in 2001.; 1999: ''Proposal of Guadalupian and Component Roadian, Wordian and Capitanian Stages as International Standards for the Middle Permian Series'', Permophiles 34: pp 3–11. The base of the Wordian Stage is defined as the place in the stratigraphic record where fossils of conodont species ''Jinogondolella aserrata'' fi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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] |
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] |
Guadalupian
The Guadalupian is the second and middle series/epoch of the Permian. The Guadalupian was preceded by the Cisuralian and followed by the Lopingian. It is named after the Guadalupe Mountains of New Mexico and Texas, and dates between 272.95 ± 0.5 – 259.1 ± 0.4 Mya. The series saw the rise of the therapsids, a minor extinction event called Olson's Extinction and a significant mass extinction called the end-Capitanian extinction event. The Guadalupian was previously known as the Middle Permian. Name and background The Guadalupian is the second and middle series or epoch of the Permian. Previously called Middle Permian, the name of this epoch is part of a revision of Permian stratigraphy for standard global correlation. The name "Guadalupian" was first proposed in the early 1900s, and approved by the International Subcommission on Permian Stratigraphy in 1996. References to the Middle Permian still exist. The Guadalupian was preceded by the Cisuralian and followed by the Lop ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aristoceras
''Aristoceras'' is a Late Paleozoic goniatitid genus included in the Goniatitina suborder in which the lobes of the external suture are irregularly serrate. ''Aristoceras'', named by Ruzencev, 1950, may be a synonym for '' Euthalassoceras'' Miller and Furnish, 1940. The family to which it belongs, the Thalassoceratidae is now part of the Thalassoceratoidea, but used to be included in the Dimorphocerataceae Dimorphoceratoidea is one of seventeen superfamilies included in the ammonoid suborder Goniatitina Goniatitina is one of two suborders included in the order Goniatitida; extinct Paleozoic Ammonoidea, ammonoid cephalopods only distantly relate ... with the Dimorphoceratidae. References * *''Aristoceras'' iGONIAT6/9/12 * Fossils of Kazakhstan Goniatitida genera Thalassoceratoidea Permian ammonites Pennsylvanian first appearances Cisuralian genus extinctions {{Goniatitida-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fossils Of Italy
A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved in amber, hair, petrified wood and DNA remnants. The totality of fossils is known as the ''fossil record''. Paleontology is the study of fossils: their age, method of formation, and evolutionary significance. Specimens are usually considered to be fossils if they are over 10,000 years old. The oldest fossils are around 3.48 billion years old to 4.1 billion years old. Early edition, published online before print. The observation in the 19th century that certain fossils were associated with certain rock strata led to the recognition of a geological timescale and the relative ages of different fossils. The development of radiometric dating techniques in the early 20th century allowed scientists to quantitatively measure the absolute ... [...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] |
Thalassoceratoidea
Thalassoceratoidea, formerly Thalassocerataceae, is a superfamily of Late Paleozoic ammonites characterized by their thick-discoidal to subglobular, involute shells with narrow or closed umbilici and biconvex growth striae with ventral sinuses. The ventral lobe of the suture, which straddles the outer rim, is wide, and bifid, with a tall median saddle. Thallassoceratoidea are gonitites and one of seventeen superfamilies in the Goniatitina suborder. Two families are now included, Bisatoceratidae and Thalassoceratidae. The somewhat older but overlapping Bisatoceratidae used to be included as a subfamily in the Goniatitidae Goniatitidae is one of three families included in the ammonoid cephalopod superfamily Goniatitoidea, known from the Lower Mississippian to the Upper Permian The Permian ( ) is a geologic period and System (stratigraphy), stratigraphic syste .... Thalassoceratidae was included in the Dimorphocerataceae. References * *Thalassoceratoidea iGONIAT6/1 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Permian Ammonites
The Permian ( ) is a geologic period and stratigraphic system which spans 47 million years from the end of the Carboniferous Period million years ago (Mya), to the beginning of the Triassic Period 251.9 Mya. It is the last period of the Paleozoic Era; the following Triassic Period belongs to the Mesozoic Era. The concept of the Permian was introduced in 1841 by geologist Sir Roderick Murchison, who named it after the region of Perm in Russia. The Permian witnessed the diversification of the two groups of amniotes, the synapsids and the sauropsids (reptiles). The world at the time was dominated by the supercontinent Pangaea, which had formed due to the collision of Euramerica and Gondwana during the Carboniferous. Pangaea was surrounded by the superocean Panthalassa. The Carboniferous rainforest collapse left behind vast regions of desert within the continental interior. Amniotes, which could better cope with these drier conditions, rose to dominance in place of their amphibian ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
