Named By: P. M. Galton - 2007.
Synonyms: Laosaurus consors.
Classification: Chordata, Reptilia, Dinosauria, Ornithischia, Genasauria, Neornithischia.
Species: O. consors (type).
Size: About 2 meters long.
Known locations: USA - Morrison Formation rocks in Utah and Wyoming.
Time period: Late Jurassic.
Fossil representation: Several individuals.
is a genus of small ornithopod dinosaur that seems to have been
widespread across Central North America during the late Jurassic.
Othnielosaurus would have been a bipedal dinosaur
relying more upon
speed and agility to stay out of the mouths of predatory dinosaurs.
Othnielosaurus like other ornithopods were
that would have focused upon eating small low growing plants. The
cheek teeth of Othnielosaurus were leaf shaped and
well suited for
slicing through softer plants, while cheeks would have probably
been present on the sides of the mouth in life to prevent plant
material spilling out of the sides.
The naming of Othnielosaurus came about from a re-evaluation of ornithopod dinosaurs starting in the late twentieth century and continuing into the early twenty-first that saw many fossils that were once attributed to genera such as Nanosaurus, Laosaurus and Othniela shuffled around and in some instances used to create the Othnielosaurus genus. The result is that some genera such as Othnielia lost most of their assigned fossils, while others such as Laosaurus lost whole species, in this case L. consors.
Othnielosaurus was named in honour of the famous American palaeontologist Othniel Charles Marsh, and this is not the first time a dinosaur was named after him, Marshosaurus and Othnielia too was also named after him. Marsh was one of the two main players to be involved in a period of American palaeontological history dubbed the Bone Wars, a fierce rivalry between Marsh and another named Edward Drinker Cope. Cope too also has an ornithopod dinosaur similar to Othnielosaurus named after him, this time just called Drinker.
- Notice of some new vertebrate fossils. - American Journal of Science and Arts 14: 249–256. - Othniel Charles Marsh - 1877.
- Notice of new dinosaurian reptiles from the Jurassic formations. - American Journal of Science and Arts 14: 514–516. - Othniel Charles Marsh - 1877.
- Skeleton of a hypsilophodontid dinosaur (Nanosaurus (?) rex) from the Upper Jurassic of Utah. - Brigham Young University Geology Series 20: 137–157.- P. M. Galton & James A. Jenson - 1973.
- Teeth of ornithischian dinosaurs (mostly Ornithopoda) from the Morrison Formation (Upper Jurassic) of the western United States. - P. M. Galton - In Horns and Beaks: Ceratopsian and Ornithopod Dinosaurs, Kenneth Carpenter (ed) - 2007.