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''Miragaia'' (named after Miragaia, the parish in Portugal and geologic unit where its remains were found) is a genus of herbivorous stegosaurid dinosaur. Its fossils have been found in Upper Jurassic rocks in Portugal. ''Miragaia'' has the longest neck known for any stegosaurian, which included at least seventeen vertebrae. ==Discovery== ''Miragaia'' is based on holotype ML 433, a nearly complete anterior half of a skeleton with partial skull (the first cranial material for a European stegosaurid).〔 The remains were found after the construction of a road between the villages of Miragaia and Sobral. The rear half of the skeleton was probably destroyed by the roadcut. The fossils were dug up in August 1999 and August 2001.〔Araújo, R., Mateus, O., Walen, A. & Christiansen, N.A., 2009, "Preparation techniques applied to a stegosaurian dinosaur from Portugal", ''Journal of Paleontological Techniques'' 5: 1-23〕 Among the recovered bones were most of the snout, a right postorbital, both angulars of the lower jaws, fifteen neck vertebrae (the first two, which articulated with the skull, were absent), two anterior dorsal vertebrae, twelve ribs, a chevron, the shoulder bones, most of the forelimbs including a possible ''os carpi intermedium'', a right first metacarpal and three first phalanges; and thirteen bony plates plus a spike.〔 The bones were not articulated but dispersed over a surface of about five to seven metres, though there was a partial concentration of fossils that could be salvaged within a single block.〔 ML 433 was found in the Miragaia Unit of the Sobral Unit, Lourinhã Formation, which dates to the late Kimmeridgian-early Tithonian (Late Jurassic, approximately 150 million years ago).〔 Octávio Mateus, Susannah Maidment and Nicolai Christiansen named and shortly described ''Miragaia'' in 2009. The type species is ''Miragaia longicollum''. The generic name refers to the village of Miragaia but also is an allusion to ''mira'', "wonderful" in Latin, and Gaia, the Earth Goddess. The specific name means "long neck" from the Latin ''longus'', "long" and ''collum'', "neck". A partial pelvis (ilium and pubic bone) and two partial dorsal vertebrae from a juvenile individual (specimen ML 433-A) were found at the same location, intermingled with the bones of the holotype, and were also assigned, as a paratype, to ''M. longicollum''.〔 Casts were made of the holotype bones and partially based on these a life-size skeletal model was constructed from polyurethane and polyester resin parts.〔 Alberto Cobos ''et alii'' in 2010 noted that all the diagnostic characters of ''Miragaia longicollum'' are based on skeletal elements that are absent in the ''Dacentrurus'' holotype found in England in layers of about the same age, while all traits that can be compared are shared by both genera. Cobos ''et alii'' therefore proposed that ''Miragaia'' is a junior synonym of ''Dacentrurus'', meaning that it is the same dinosaur, because it is not possible to differentiate the two taxa through their holotypes. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Miragaia (dinosaur)」の詳細全文を読む スポンサード リンク
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