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Thecodontosaurus Gibbidens
''Thecodontosaurus'' ("socket-tooth lizard") is a genus of herbivorous basal sauropodomorph dinosaur that lived during the late Triassic period (Rhaetian age). Its remains are known mostly from Triassic "fissure fillings" in South England. ''Thecodontosaurus'' was a small bipedal animal, about 2 m (6.5 ft) long. It is one of the first dinosaurs to be discovered and is one of the oldest that existed. Many species have been named in the genus, but only the type species ''Thecodontosaurus antiquus'' is seen as valid today. Discovery and naming ''Thecodontosaurus antiquus'' In the autumn of 1834, surgeon Henry Riley (1797–1848) and the curator of the Bristol Institution, Samuel Stutchbury, began to excavate "saurian remains" at the quarry of Durdham Down, at Clifton, presently a part of Bristol, which is part of the Magnesian Conglomerate. In 1834 and 1835, they briefly reported on the finds. They provided their initial description in 1836, naming a new genu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rhaetian
The Rhaetian is the latest age of the Triassic Period (in geochronology) or the uppermost stage of the Triassic System (in chronostratigraphy). It was preceded by the Norian and succeeded by the Hettangian (the lowermost stage or earliest age of the Jurassic). The base of the Rhaetian lacks a formal GSSP, though candidate sections include Steinbergkogel in Austria (since 2007) and Pignola-Abriola in Italy (since 2016). The end of the Rhaetian (and the base of the overlying Hettangian Stage) is more well-defined. According to the current ICS (International Commission on Stratigraphy) system, the Rhaetian ended ± 0.2 Ma (million years ago). In 2010, the base of the Rhaetian (i.e. the Norian-Rhaetian boundary) was voted to be defined based on the first appearance of '' Misikella posthernsteini'', a marine conodont. However, there is still much debate over the age of this boundary, as well as the evolution of ''M. posthernsteini''. The most comprehensive source of precise age ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
