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Sinohelicoprion
''Sinohelicoprion'' ("Chinese spiral jaw") is an extinct genus of helicoprinid eugeneodontid fish that lived during the late Permian 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 Paleoz ... 254 to 252 million years ago and became extinct during the Permian-Triassic extinction event. It was first named and classified by H. T. Liu and M. N. Chang in 1963. Gallery Sinohelicoprion description.jpg, Information board about Sinohelicoprion in Paleozoological Museum of China. References Agassizodontidae Permian fish of Asia {{paleo-shark-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sinohelicoprion Changhsingensis
''Sinohelicoprion'' ("Chinese spiral jaw") is an extinct genus of helicoprinid eugeneodontid fish that lived during the late Permian 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 Paleoz ... 254 to 252 million years ago and became extinct during the Permian-Triassic extinction event. It was first named and classified by H. T. Liu and M. N. Chang in 1963. Gallery Sinohelicoprion description.jpg, Information board about Sinohelicoprion in Paleozoological Museum of China. References Agassizodontidae Permian fish of Asia {{paleo-shark-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paleozoological Museum Of China
The Paleozoological Museum of China (PMC; ) is a museum in Beijing, China. The same building also houses the Institute of Vertebrate Paleontology and Paleoanthropology of the Chinese Academy of Sciences. The museum contains exhibition halls with specimens aimed at the public, while the rest of the building is used for research purposes. Building The main building consists of three floors, with the first floor displaying a number of fish and amphibian fossils, along with many Mesozoic reptiles, while reptiles and birds are represented on the second floor, and mammals (including examples of megafauna like Stegodon) on the third floor. Many of the fossil specimens on display are of extinct animals examples of which have only been found within the boundaries of modern-day China, such as ''Sinokannemeyeria''. It also has several examples of the evolutionary precursors to birds, including the holotypes of ''Confuciusornis'' and ''Microraptor'', found on field expeditions to Liaoning. An ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Helicoprionidae
The Helicoprionidae, also known as the Agassizodontidae are an extinct, poorly known family of bizarre holocephalids within the poorly understood order Eugeneodontida. Members of the Helicoprionidae possessed a unique "tooth-whorl" on the symphysis of the lower jaw and pectoral fins supported by long radials. The closest living relatives of the Helicoprionidae and all other eugeneodontids are the ratfishes. The anatomy of the tooth-whorl differed amongst genus and species, some possessing complete spirals (such as those of ''Helicoprion ''Helicoprion'' is an extinct genus of shark-like eugeneodont fish. Almost all fossil specimens are of spirally arranged clusters of the individuals' teeth, called "tooth whorls", which in life were embedded in the lower jaw. As with most extin ...''), others possessing halved spirals (seen in '' Parahelicoprion''), and some with wedged half-spirals (seen in '' Sarcoprion''). Each tooth-whorl is thought to be adapted to a different type of p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Agassizodontidae
The Helicoprionidae, also known as the Agassizodontidae are an extinct, poorly known family of bizarre holocephalids within the poorly understood order Eugeneodontida. Members of the Helicoprionidae possessed a unique "tooth-whorl" on the symphysis of the lower jaw and pectoral fins supported by long radials. The closest living relatives of the Helicoprionidae and all other eugeneodontids are the ratfishes. The anatomy of the tooth-whorl differed amongst genus and species, some possessing complete spirals (such as those of ''Helicoprion''), others possessing halved spirals (seen in ''Parahelicoprion ''Parahelicoprion'' is an extinct genus of shark-like eugeneodontid holocephalids from the Permian of the Ural Mountains (Russia) and Copacabana Formation, Bolivia. The genus name, from "nearly coiled saw" in Greek, directly refers to ''Helico ...''), and some with wedged half-spirals (seen in '' Sarcoprion''). Each tooth-whorl is thought to be adapted to a different type of pre ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lopingian
The Lopingian is the uppermost series/last epoch of the Permian. It is the last epoch of the Paleozoic. The Lopingian was preceded by the Guadalupian and followed by the Early Triassic. The Lopingian is often synonymous with the informal terms late Permian or upper Permian. The name was introduced by Amadeus William Grabau in 1931 and derives from Leping, Jiangxi in China. It consists of two stages/ ages. The earlier is the Wuchiapingian and the later is the Changhsingian. The International Chronostratigraphic Chart (v2018/07) provides a numerical age of 259.1 ±0.5 Ma. If a Global Boundary Stratotype Section and Point (GSSP) has been approved, the lower boundary of the earliest stage determines numerical age of an epoch. The GSSP for the Wuchiapingian has a numerical age of 259.8 ± 0.4 Ma. Evidence from Milankovitch cycles suggests that the length of an Earth day during this epoch was approximately 22 hours. The Lopingian ended with the Permian–Triassic extinction event. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eugeneodontida
The Eugeneodontida is an extinct and poorly known order of cartilaginous fishes. They possessed "tooth-whorls" on the symphysis of either the lower or both jaws and pectoral fins supported by long radials. They probably lacked pelvic fins and anal fins. The palatoquadrate was either fused to the skull or reduced. Now determined to be within the Holocephali, their closest living relatives are ratfish. The eugeneodonts are named after paleontologist Eugene S. Richardson, Jr. The Eugeneodontida disappeared in the Early Triassic. Members of the Eugeneodontida are further classified into different families, the most well-preserved members that have been discovered are commonly placed within the families Helicoprionidae ("spiral saws"), and Edestidae ("those which devour"), the former containing the genera ''Helicoprion'', '' Sarcoprion'', and '' Parahelicoprion'', and the latter containing the genera '' Edestus'', ''Lestrodus'', and '' Metaxyacanthus''. All eugeneodonts are thought ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Permian
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 am ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
