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Silurolepis
''Silurolepis platydorsalis'' is an extinct species of Silurian-aged "maxillate" placoderm that has been described from (mostly) articulated remains. Although it has been known for several years, it was finally described by Zhang, et al., in 2010. The earliest described placoderm is the yunnanolepid antiarch, ''Shimenolepis'', from Llandovery Hunan. In contrast to ''S. platydorsalis'', ''Shimenolepis'' is known only from distinctively ornamented thoracic armor plates that bear anatomic features unique to yunnanolepids. ''S. platydorsalis'' was previously considered a basal antiarch, but a 2019 study instead recovers it as a maxillate placoderm most closely related to ''Qilinyu ''Qilinyu rostrata'' is a "maxillate" placoderm from the late Ludlow epoch of Qujing, Yunnan, 419 million years ago.Zhu, Min, et al. "A Silurian maxillate placoderm illuminates jaw evolution." Science 354.6310 (2016): 334-336/ref> Specimens and ...''. ''S. platydorsalis'' is known from thoracic a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Placoderms Of Asia
Placodermi (from Greek πλάξ 'plate' and δέρμα 'skin', literally ' plate-skinned') is a class of armoured prehistoric fish, known from fossils, which lived from the Silurian to the end of the Devonian period. Their head and thorax were covered by articulated armoured plates and the rest of the body was scaled or naked, depending on the species. Placoderms were among the first jawed fish; their jaws likely evolved from the first of their gill arches. Placoderms are thought to be paraphyletic, consisting of several distinct outgroups or sister taxa to all living jawed vertebrates, which originated among their ranks. In contrast, one 2016 analysis concluded that placodermi are likely monophyletic, though these analyses have been further dismissed with more transitional taxa between placoderms and modern gnathosthomes, solidifying their paraphyletic status. Placoderms were also the first fish to develop pelvic fins, the precursor to hindlimbs in tetrapods, as well as tru ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Qilinyu
''Qilinyu rostrata'' is a "maxillate" placoderm from the late Ludlow epoch of Qujing, Yunnan, 419 million years ago.Zhu, Min, et al. "A Silurian maxillate placoderm illuminates jaw evolution." Science 354.6310 (2016): 334-336/ref> Specimens and taxonomy The holotype and paratype of ''Q. rostrata'' are two exquisitely preserved specimens both featuring a domed cranium and a curved rostrum presenting a "dolphin-like profile." The researchers' cladistic diagram shows ''Q. rostrata'' as the sister taxon of ''Entelognathus'', ''Janusiscus'' and the crown gnathostomes (i.e., bony and cartilaginous fishes and their descendants). Evolutionary significance ''Qilinyu rostrata'', together with ''Entelognathus'', demonstrates additional evidence that modern gnathostomes evolved from placoderms.Long, John A. "The first jaws." Science 354.6310 (2016): 280-281. See also * ''Entelognathus'' * ''Bianchengichthys'' * ''Silurolepis ''Silurolepis platydorsalis'' is an extinct species ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ludlow Epoch
In the geological timescale, the Ludlow Epoch (from 427.4 ± 0.5 million years ago to 423.0 ± 2.3 million years ago) occurred during the Silurian Period, after the end of the Homerian Age. It is named for the town of Ludlow in Shropshire, England. The Ludlow Epoch is subdivided into two stages: Gorstian and Ludfordian. Paleontology Arthropods See also *Ludlow Group References Ludlow epoch, Silurian geochronology, *03 Geological epochs Ludlow first appearances, {{geochronology-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Silurian
The Silurian ( ) is a geologic period and system spanning 24.6 million years from the end of the Ordovician Period, at million years ago ( Mya), to the beginning of the Devonian Period, Mya. The Silurian is the shortest period of the Paleozoic Era. As with other geologic periods, the rock beds that define the period's start and end are well identified, but the exact dates are uncertain by a few million years. The base of the Silurian is set at a series of major Ordovician–Silurian extinction events when up to 60% of marine genera were wiped out. One important event in this period was the initial establishment of terrestrial life in what is known as the Silurian-Devonian Terrestrial Revolution: vascular plants emerged from more primitive land plants, dikaryan fungi started expanding and diversifying along with glomeromycotan fungi, and three groups of arthropods (myriapods, arachnids and hexapods) became fully terrestrialized. A significant evolutionary milestone during ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Palaeoworld
''Palaeoworld'' is a peer-reviewed academic journal with a focus on palaeontology and stratigraphy research in and around China. It was founded in 1991 by the Nanjing Institute of Geology and Palaeontology at the Chinese Academy of Sciences (NIGPAS). The journal has been published quarterly since 2006; prior to 2006, it did not adhere to a fixed publication schedule. The journal publishes articles from several specialised fields pertaining to palaeobiology and earth science, such as: fossil taxonomy; biostratigraphy, chemostratigraphy, and chronostratigraphy; evolutionary biology; evolutionary ecology; palaeoecology; palaeoclimatology; and molecular palaeontology. Its editors-in-chief are Shuzhong Shen of the State Key Laboratory of Palaeobiology and Stratigraphy at NIGPAS, and Norman MacLeod of the Natural History Museum, London. See also * ''Paleontological Journal'' * List of fossil sites This list of fossil sites is a worldwide list of localities known well for th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Yunnanolepiformes
Antiarchi ("opposite anus") is an order of heavily armored placoderms. The antiarchs form the second-most successful group of placoderms after the arthrodires in terms of numbers of species and range of environments. The order's name was coined by Edward Drinker Cope, who, when examining some fossils that he thought were armored tunicates related to '' Chelysoma'', mistakenly thought that the orbital fenestra (i.e., the hole in the headshield for the eyes, nose and pineal foramen) was the opening for the mouth, or oral siphon, and that the opening for the anal siphon was on the other side of the body, as opposed to having both oral and anal siphons together at one end. The front portions of their bodies were heavily armored, to the point of literally resembling a box with eyes, with the sometimes scaled, sometimes naked rear portions often becoming sinuous, particularly with later forms. The pair of pectoral fins were modified into a pair of caliper-like, or arthropod-like ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shimenolepis
''Shimenolepis granifera'' is an extinct yunnanolepid placoderm from the Late Llandovery of Li County, Hunan Li County, or Lixian () is a county in Hunan Province, China, it is under the administration of the prefecture-level city of Changde. The County is located on the north in Hunan Province, it borders to the north by Songzi City and Gong'an Count ..., China. It was the first described Silurian placoderm, and is the earliest known placoderm, known from distinctively ordered plates. Description Plates ''Shimenolepis'' plates are very similar to the early Devonian yunnanolepid '' Zhanjilepis'', also known from distinctively ornamented plates. References Placoderms of Asia Prehistoric animals of China Antiarchi Silurian fish of Asia {{Placoderm-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hunan
Hunan (, ; ) is a landlocked province of the People's Republic of China, part of the South Central China region. Located in the middle reaches of the Yangtze watershed, it borders the province-level divisions of Hubei to the north, Jiangxi to the east, Guangdong and Guangxi to the south, Guizhou to the west and Chongqing to the northwest. Its capital and largest city is Changsha, which also abuts the Xiang River. Hengyang, Zhuzhou, and Yueyang are among its most populous urban cities. With a population of just over 66 million residing in an area of approximately , it is China's 7th most populous province, the fourth most populous among landlocked provinces, the second most populous in South Central China after Guangdong and the most populous province in Central China. It is the largest province in South-Central China and the fourth largest among landlocked provinces and the 10th most extensive province by area. Hunan's nominal GDP was US$ 724 billion (CNY 4.6 trillion) a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antiarch
Antiarchi ("opposite anus") is an order of heavily armored placoderms. The antiarchs form the second-most successful group of placoderms after the arthrodires in terms of numbers of species and range of environments. The order's name was coined by Edward Drinker Cope, who, when examining some fossils that he thought were armored tunicates related to '' Chelysoma'', mistakenly thought that the orbital fenestra (i.e., the hole in the headshield for the eyes, nose and pineal foramen) was the opening for the mouth, or oral siphon, and that the opening for the anal siphon was on the other side of the body, as opposed to having both oral and anal siphons together at one end. The front portions of their bodies were heavily armored, to the point of literally resembling a box with eyes, with the sometimes scaled, sometimes naked rear portions often becoming sinuous, particularly with later forms. The pair of pectoral fins were modified into a pair of caliper-like, or arthropod-like l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Silurian Fish Of Asia
The Silurian ( ) is a geologic period and system spanning 24.6 million years from the end of the Ordovician Period, at million years ago ( Mya), to the beginning of the Devonian Period, Mya. The Silurian is the shortest period of the Paleozoic Era. As with other geologic periods, the rock beds that define the period's start and end are well identified, but the exact dates are uncertain by a few million years. The base of the Silurian is set at a series of major Ordovician–Silurian extinction events when up to 60% of marine genera were wiped out. One important event in this period was the initial establishment of terrestrial life in what is known as the Silurian-Devonian Terrestrial Revolution: vascular plants emerged from more primitive land plants, dikaryan fungi started expanding and diversifying along with glomeromycotan fungi, and three groups of arthropods (myriapods, arachnids and hexapods) became fully terrestrialized. A significant evolutionary milestone durin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
