Name:
Osmakasaurus
(Osmaka lizard - Osmaka is the Lakota word for ‘canyon’,
which in this aspect is a reference to the Buffalo gap in South
Dakota).
Phonetic: Os-mak-ah-sore-us.
Named By: Andrew T. McDonald - 2011.
Synonyms: Camptosaurus depressus,
Planicoxa depressa.
Classification: Chordata, Reptilia, Dinosauria,
Ornithischia, Ornithopoda, Iguanodontia?
Species: O. depressus
(type).
Diet: Herbivore.
Size: Precise size uncertain due to lack of
remains, but estimated to be in the region of about 4-5 meters
long.
Known locations: USA, South Dakota - Lakota
Formation, Chilson Member.
Time period: Late Barremian of the Cretaceous.
Fossil representation: Post cranial remains,
specifically an ilium and some vertebrae.
Originally named as a species of Camptosaurus 1909 (Gilmore), and then later Planicoxa in 2008 (Carpenter & Wilson), Osmakasaurus was established as a new genus for partial post cranial remains that establish this genus. The species name ‘depressus’ has been retained to create the type species, which is standard procedure when naming a new genus from a previously described species. The actual species name O. depressus is a reference to the sunken blade of the ilium of this genus. Unfortunately it is not possible to say much more about this dinosaur, though Osmakasaurus has been considered to be an ignuanodontid, and given its previous association to Camptosaurus and Planicoxa, it’s fair to establish that Osmakasaurus would have been similar to other medium to large iguanodontid genera that are typified by Iguanodon.
Further reading
- The taxonomy of species assigned to Camptosaurus
(Dinosauria:
Ornithopoda). - Zootaxa. 2783: 52–68. - Andrew T. McDonald - 2011.
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