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Yunnanolepididae
Yunnanolepididae is an extinct family of primitive Antiarch placoderms characterized by having short, broad skull roofs, and by having a feature on the visceral side of the posterior medial dorsal plate, the ''crista transversalis interna posterior'', which is diagnostic of antiarchs, turning forward, and lying in front of the posterior ventral process and pit (with this position being diagnostic of yunnanolepids in particular). At least three genera, ''Yunnanolepis'', ''Phymolepis'', and ''Vukhuclepis'' are confirmed to have a unique organ called the "Chang's Apparatus," named in honor of Professor Meemann Chang, which is an internal cavity with an external opening within the suture of the anterior dorsal lateral plate and the anterior ventral lateral plate. The other genera in Yunnanolepidae that are not confirmed to have the Chang's Apparatus are included in the family because of anatomical similarities to ''Yunnanolepis''. The fossils of the various genera are found in Early ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vukhuclepis
''Vukhuclepis lyhoaensis'' is an extinct, primitive antiarch placoderm. Specimens are of mostly complete thoracic armor from the Early Devonian Ly Hoa Formation in Vietnam. The armor is very similar to that of ''Yunnanolepis ''Yunnanolepis'' is an extinct genus of primitive antiarch placoderm. The fossils of the various species are found in Early to Middle Devonian strata in Southern China ( Xishancun, Lianhuashan and Xitun Formations). External links ''Yunnanol ...'', but is distinguished by a unique pattern of raised ridges radiating from a point at the center of the dorsal shield of the thoracic armor. A similar, albeit more floral-looking pattern is seen in the Chinese '' Mizia''. ''V. lyhaoensis armor is further ornamented with small tubercles. References Antiarchi Placoderm genera Placoderms of Asia Lochkovian life Fossils of Vietnam Fossil taxa described in 1996 {{placoderm-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phymolepis
''Phymolepis'' is an extinct genus of yunnanolepidid placoderm from the Early Devonian of China. The type species, ''P. cuifengshanensis'', was named by Zhang Goroui in 1978Chang, K-J. (1978). Symposium on the Devonian System of South China: Early devonian antiarchs from Cuifengshan, Yunnan. ''Institute of Geology and Mineral Resources of the Chinese Academy of Geological Sciences'', ed. Geological Press; Beijing: 1978; pp. 292–297.Zhang, G. (1978). The antiarchs from the Early Devonian of Yunnan. ''Vertebrata PalAsiatica''. 1978;16:147–186. and was re-evaluated in 2018, while a second species, ''P. guoruii'', was named and described in 1996. The holotype of ''P. cuifengshanensis'' is IVPP V4225.3, a nearly complete trunk shield, and it was found in the Xitun Formation, near Cuifengshan. The paratype is IVPP V4425.6, a posterior median dorsal plate, and several other specimens of varying completeness have also been referred to ''Phymolepis'', with some specimens also bein ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Devonian
The Devonian ( ) is a geologic period and system of the Paleozoic era, spanning 60.3 million years from the end of the Silurian, million years ago (Mya), to the beginning of the Carboniferous, Mya. It is named after Devon, England, where rocks from this period were first studied. The first significant adaptive radiation of life on dry land occurred during the Devonian. Free-sporing vascular plants began to spread across dry land, forming extensive forests which covered the continents. By the middle of the Devonian, several groups of plants had evolved leaves and true roots, and by the end of the period the first seed-bearing plants appeared. The arthropod groups of myriapods, arachnids and hexapods also became well-established early in this period, after starting their expansion to land at least from the Ordovician period. Fish reached substantial diversity during this time, leading the Devonian to often be dubbed the Age of Fishes. The placoderms began dominating ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
China
China, officially the People's Republic of China (PRC), is a country in East Asia. It is the world's most populous country, with a population exceeding 1.4 billion, slightly ahead of India. China spans the equivalent of five time zones and borders fourteen countries by land, the most of any country in the world, tied with Russia. Covering an area of approximately , it is the world's third largest country by total land area. The country consists of 22 provinces, five autonomous regions, four municipalities, and two Special Administrative Regions (Hong Kong and Macau). The national capital is Beijing, and the most populous city and financial center is Shanghai. Modern Chinese trace their origins to a cradle of civilization in the fertile basin of the Yellow River in the North China Plain. The semi-legendary Xia dynasty in the 21st century BCE and the well-attested Shang and Zhou dynasties developed a bureaucratic political system to serve hereditary monarchies, or dyna ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fossils Of Vietnam
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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fossils Of China
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] |
Antiarchi
Antiarchi ("opposite anus") is an order (biology), 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 wiktionary:sinuous, sinuous, particularly with later forms. The pair of pectoral fins were modified into a pair of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Prehistoric Fish Of Asia
Prehistory, also known as pre-literary history, is the period of human history between the use of the first stone tools by hominins 3.3 million years ago and the beginning of recorded history with the invention of writing systems. The use of symbols, marks, and images appears very early among humans, but the earliest known writing systems appeared 5000 years ago. It took thousands of years for writing systems to be widely adopted, with writing spreading to almost all cultures by the 19th century. The end of prehistory therefore came at very different times in different places, and the term is less often used in discussing societies where prehistory ended relatively recently. In the early Bronze Age, Sumer in Mesopotamia, the Indus Valley Civilisation, and ancient Egypt were the first civilizations to develop their own scripts and to keep historical records, with their neighbors following. Most other civilizations reached the end of prehistory during the following Iron Age. Th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
