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''Yaguarasaurus'' is an extinct genus of mosasauroid from the Late Cretaceous (Turonian) period of Colombia, South America. The remains discovered (an articulated skull, some vertebrae and ribs) were defined as a new genus and species of mosasaurid, ''Yaguarasaurus columbianus'', by the Colombian paleontologist María Páramo, former director of the Museo de Geología José Royo y Gómez of INGEOMINAS in Bogota. The remains were found in a limestone bench (Upper Turonian) of the Villeta Formation near Yaguará, in the site called Cueva Rica (Huila). Its name means "Yaguará lizard of Colombia". The first fossils remains of this animal suggested a cranial length of 47 cm and a total length of 5 meters; an additional skull that measures 87 cm long implies a larger size.〔Páramo, M.E. 2000. ''Yaguarasaurus columbianus'' (Reptilia, Mosasauridae), a primitive mosasaur from the Turonian (Upper Cretaceous) of Colombia. ''Historical Biology'', 14: 121-131.〕 This reptile is a member of the family of marine lizards Mosasauridae characteristic of Middle and Upper Cretaceous, with global distribution, but in South America known only through isolated remains (Price, 1957, Pierce and Welles, 1959 ; Bonaparte, 1978;〔Bonaparte, J. F., 1978, ''El Mesozoico de América del Sur y sus Tetrápodos'': Ministerio de Cultura y Educación Fundación Miguel Lillo, San Miguel de Tucumán, Opera Lilloana v. 26, 596pp.〕 Ameghino, 1918). This mosasaur discovered in Yaguará, is the most complete material known in South America.〔Páramo, M. E., 1994, Posición sistemática de un reptil marino con base en los restos fósiles encontrados en capas del Cretácico Superior en Yaguará (Huila): ''Revista de la Academia Colombiana de Ciencias Exactas, Físicas y Naturales'', v. 19, n. 72, p. 63-80〕 == Phylogeny == In the initial descriptions of ''Yaguarasaurus'' it was classified as a member of the subfamily Plioplatecarpinae;〔 the analysis of Polcyn and Bell, 2005 showed that it was a distant relative of the advanced mosasaurids and were a close relative of ''Russellosaurus coheni'' and ''Tethysaurus nopscai'', a group that could be a basal clade to the division between Tylosaurinae and Plioplatecarpinae subfamilies, called Russellosaurina.〔Polcyn, M. J. and Bell, G. L., Jr. 2005. ''Russellosaurus coheni'' n. gen., n. sp., a 92 million-year-old mosasaur from Texas (USA), and the definition of the parafamily Russellosaurina. N''etherlands Journal of Geosciences'' 84(3):321-333.〕 After the discovery of the basal mosasauroid of Hungary ''Pannoniasaurus'' by Makádi et al. 2012 it became clear that ''Yaguarasaurus'' and the rest of the "russellosaurines" form a clade of basal amphibian mosasaurs related with the aigialosaurs, a grouping called the subfamily Tethysaurinae; the cladogram below follow the analysis of Makádi ''et al.'' de 2012: }} }} Palci et al. (2013) describe a new Russellosaurine, ''Romeosaurus'', and created subfamily Yaguarasaurinae, sister group of Tethysaurinae }} }} 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「Yaguarasaurus」の詳細全文を読む スポンサード リンク
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