Thespesius

Taxobox
name = "Thespesius"
fossil_range = Upper Cretaceous

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image_width = 250px
image_caption = Illustration of "Thespesius" from 1901.
regnum = Animalia
phylum = Chordata
classis = Sauropsida
superordo = Dinosauria
ordo = Ornithischia
familia = Hadrosauridae
subfamilia = ?Hadrosaurinae
genus = "Thespesius"
genus_authority=Leidy, 1856
subdivision_ranks=Species
subdivision=
*"T. occidentalis" Leidy, 1856 (type)

"Thespesius" (meaning "wondrous one") is a dubious genus of hadrosaurid dinosaur based on two caudal vertebrae and a phalanx from the late Maastrichtian-age Upper Cretaceous Lance Formation of South Dakota (although at first thought to to be from the Miocene).Leidy, J. (1856). Notice of extinct Vertebrata, discovered by Dr. F. V. Hayden during the expedition to the Sioux country under the command of Lieut. G.K. Warren. "Proceedings of the Academy of Natural Science Philadelphia" 8:311-312.] Like "Trachodon", another duckbill genus named by Joseph Leidy, it is an historically-important genus with a convoluted taxonomy that has been all but abandoned by modern dinosaur paleontologists.Creisler, B.S. (2007). Deciphering duckbills. in: K. Carpenter (ed.), "Horns and Beaks: Ceratopsian and Ornithopod Dinosaurs". Indiana University Press: Bloomington and Indianapolis, 185-210. ISBN 0-253-34817-X]

Two other species of duckbill started out as species of "Thespesius": "T. saskatchewanensis",Sternberg, C.M. (1926). A new species of "Thespesius" from the Lance Formation of Saskatchewan. "Canada Department of Mines Geological Survey Bulletin (Geological Series)" 44(46):73-84.] now thought to be a species of "Edmontosaurus;"Weishampel, D.B., and Horner, J.R. (1990). Hadrosauridae. In: Weishampel, D.B., Dodson, P., and Osmólska, H. (eds.). "The Dinosauria." University of California Press:Berkeley, 534-561. ISBN 0-520-24209-2] Horner, J.R., Weishampel, D.B., and Forster, C.A. (2004). Hadrosauridae. In: Weishampel, D.B., Dodson, P., and Osmólska, H. (eds.). "The Dinosauria (second edition)". University of California Press:Berkeley, 438-463. ISBN 0-520-06727-4] and "T. edmontoni",Gilmore, C.W. (1924). A new species of hadrosaurian dinosaur from the Edmonton Formation (Cretaceous) of Alberta. "Canada Department of Mines Geological Survey Bulletin (Geological Series)" 38(43):13-26.] now considered to be the same as "Edmontosaurus annectens". Both of them were included in "Anatosaurus" for many years.Lull, R.S., and Wright, N.E. (1942). Hadrosaurian Dinosaurs of North America. "Geological Society of America Special Paper 40":1-242.]

References