Othnielia is a
genus of hypsilophodont dinosaur, named after its original describer,
Professor Othniel Charles Marsh, an American paleontologist of the
- See Othnielosaurus
for more information.
, was named by Peter Galton
1977 from a species Marsh (1877) called Nanosaurus
assigned to Othnielia have been found in Wyoming, Utah, and
Colorado in rocks of
the Late Jurassic age (Oxfordian-Tithonian) Morrison
Formation, but with Galton's 2007 revision of Morrison ornithischians, the only definite remains are
1875 (the holotype femur of "Nanosaurus" 'rex')
and possibly some other associated postcranial bits.
He considered the femur
undiagnostic and thus Othnielia
to be a dubious name, and
removed two partial skeletons to the new genus
. It remains to be seen if this will be
widely accepted, but this sort of taxonomic decision has much
precedent (for example, Marasuchus
Without the remains now included in Othnielosaurus
, this animal is dubious
, and can only be described in
generalities based on similar animals. It was relatively small for
a dinosaur, at around long, and in weight, and an agile bipedal herbivore
proportionally small arms and long legs. Animals of this genus were
included in the novel Jurassic
as "othys", tree-climbing small herbivores, although
there is no evidence for this kind of behavior.
Only the original holotype of Othnielia
and two partial
skeletons were specifically dealt with in Galton's paper, leaving
unsettled the assignment of several other specimens that have
appeared in the literature. Included among these are a nearly complete
specimen in the Aathal Museum
nicknamed "Barbara" is probably referable, as well as some juvenile
remains (DMNH 21716, a partial skeleton tentatively referred by
Brill and Carpenter  to Othnielia rex) and a dentary
(MWC 5822, again referred to O. rex). Skeletons identified
as Othnielia are also on display at the Denver Museum of
Nature and Science.
A herd of Othnielia rex
scampering at the Denver Museum of Nature and Science.
- Marsh, O.C. (1877). Notice of new dinosaurian reptiles from the
Jurassic formations. American Journal of Sciences (Series
- Galton, P.M. (1977). The ornithopod dinosaur Dryosaurus and a
Laurasia-Gondwanaland connection in
the Upper Jurassic. Nature 268: 230-232.
- Foster, J.R. (2003). Paleoecological Analysis of the
Vertebrate Fauna of the Morrison Formation (Upper Jurassic), Rocky
Mountain Region, U.S.A. New Mexico Museum of Natural
History and Science Bulletin 23.
- Galton, P.M. (2007). Teeth of ornithischian dinosaurs (mostly
Ornithopoda) from the Morrison Formation (Upper Jurassic) of the
western United States. in: Carpenter, K. (ed.). Horns and
Beaks: Ceratopsian and Ornithopod Dinosaurs. Indiana
University Press: Bloomington, 17-47. ISBN 0-253-34817-X.