Named By: Thomas Henry Huxley - 1877.
Synonyms: Dasygnathus longidens, Ornithosuchus taylori, Ornithosuchus woodwardi.
Classification: Chordata, Reptilia, Archosauria, Crurotarsi, Pseudosuchia, Ornithosuchidae.
Species: O. longidens (type).
Size: 4 meters long.
Known locations: Scotland.
Time period: Carnian of the Triassic.
Fossil representation: At least three specimens.
the last part of the name, suchus, translates to English as
crocodile, Ornithosuchus was actually an
archosaur. These were the
dominant reptiles of the Triassic some of which would diverge into true
crocodiles, while others would take different paths to evolve into
the dinosaurs. In fact the long hind legs that would have allowed for
a bipedal stance were once taken as a sign that Ornithosuchus
very primitive dinosaur, although modern analysis places it more
firmly within the Archosauria. This identification is based upon the
five towed feet, the number of skull fenestra (holes) as well as
the joints of the ankles and spine to the hips.
Because the long hind legs were directly underneath the hips Ornithosuchus was easily able to attain a bipedal stance. However it’s more likely that the typical resting posture of Ornithosuchus was quadrupedal, with bipedal posture only taking over when Ornithosuchus was chasing after and attacking prey. This would have allowed for greater speed as well as reach for Ornithosuchus to find a weaker spot on the prey. This high bite angle could explain why the archosaurs developed bony armour along their backs, particularly in herbivorous members such as as Desmatosuchus.
Ornithosuchus was roughly mid-range in size for the archosaurs and since it was larger than many of the other known archosaurs. However Ornithosuchus probably had to mind its step when dealing with other larger members of the group which could grow up to five to six meters long as seen with the Polish archosaur Smok.
- Triassic reptiles from the Elgin area: Ornithosuchus and the origin of carnosaurs - Philosophical Transactions of the Royal Society of London. Series B, Biological Sciences, 248(744): 53-134. - A. D. Walker - 1964.