Shuangmiaosaurus is a genus of herbivorous iguanodontian ornithopod dinosaur which lived in China during the Late Cretaceous Period, about 100 million years ago.Carpenter, K. and Ishida, Y. (2010). "Early and “Middle” Cretaceous Iguanodonts in Time and Space. " Journal of Iberian Geology, 36 (2): 145-164
The type species, Shuangmiaosaurus gilmorei, was named and described by You Hailu, Ji Qiang Li Jinglu and Li Yinxian in 2003. The generic name refers to the village of Shuangmiao in Beipiao in Liaoning Province, the site of the discovery. The specific name honours the American paleontologist Charles Whitney Gilmore.H. You, Q. Ji, J. Li and Y. Li, 2003, "A new hadrosauroid dinosaur from the mid-Cretaceous of Liaoning, China", Acta Geologica Sinica 77(2): 148-154
The holotype, specimen LPM 0165, was found in the Sunjiawan Formation dating to the Late Cretaceous (Cenomanian). It consists of a partial left upper jaw and lower jaw, including the maxilla, part of the premaxilla, elements of the lacrimal and the dentary. It was a rather large ornithopod, estimated at in length and in body mass.Paul, G.S., 2010, The Princeton Field Guide to Dinosaurs, Princeton University Press p. 294
Shuangmiaosaurus was originally considered a basal member of the Hadrosauroidea, one closely related to the Hadrosauridae. Subsequent authors, including David B. Norman of Cambridge University, consider it a more basal member of the Iguanodontia outside of the Hadrosauroidea.Norman, D.B. (2004). "Basal Iguanodontia." In D. B. Weishampel, P. Dodson, and H. Osmólska (eds.), The Dinosauria (2nd edition). University of California Press, Berkeley 413-437
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