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''Cathetosaurus'' is a dinosaur sauropod genus that contains one species: ''Cathetosaurus lewisi'' that was thought to be within the ''Camarasaurus'' genus. The holotype specimen was originally described by James Jensen and is now in the Brigham Young University collection. The holotype specimen of ''Cathetosaurus lewisi'' is contemporary with the middle of the ''C. grandis'' age range. It is supposedly different from other species due to the bifurcation (split) of its neck vertebrae starting at a different point in the neck, and bony tendons present in the hip region. However, no other ''Camarasaurus'' specimens are well preserved enough to be sure the supposedly distinct neck vertebrae are really distinct, and bony hip tendons are also known in large, mature specimens of ''C. lentus'' and ''C. supremus'', indicating that this difference may be a feature that changed with age.〔Ikejiri, T. (2005). Distribution and biochronology of Camarasaurus (Dinosauria, Sauropoda) from the Jurassic Morrison Formation of the Rocky Mountain Region. In New Mexico Geological Society, 56th Field Conference Guidebook, Geology of the Chama Basin (pp. 367-379).〕 This species was originally named as ''Cathetosaurus lewisi'' and later synonymized with ''Camarasaurus''. More recent research has split the two genera again, based on the recognition of a second specimen.〔Mateus, O., & Tschopp E. (2013). ''Cathetosaurus'' as a valid sauropod genus and comparisons with ''Camarasaurus''. Journal of Vertebrate Paleontology, Program and Abstracts, 2013. 173.〕 The diagnostic characters for ''Cathetosaurus'' are:〔 * the pelvis is rotated anteriorly, such that the pubis projects posteroventrally, and the ischium projects posteriorly, * lateroventrally projecting spurs in the neural spines of the last dorsals; * posterior cervical and anterior dorsal diapophyses bearing an anterior projection lateral to the prezygapophysis. * frontals with anterior midline projection into the nasals; * trapezoidal supraoccipital (more expanded dorsally than ventrally), * lateral spur on the dorsal part of the lacrimal, iv) fenestrated pterygoid; * the large pineal foramen between the frontals. ==References== 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「Cathetosaurus」の詳細全文を読む スポンサード リンク
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