Named By: X. Xu & X. Wang - 2004.
Classification: Chordata, Reptilia, Dinosauria, Saurischia, Theropoda, Troodontidae.
Species: S. magnodens (type).
Size: Roughly about 1-1.2 meters long.
Known locations: China, Liaoning Province - Yixian Formation [Lujiatun Member].
Time period: Hauterivian of the Cretaceous.
Fossil representation: Skull and partial post cranial skeleton.
Sinusonasus is a genus of troodontid dinosaur that lived in China during the early Cretaceous. Sinusonasus means ‘wave nose’, and this name was given after the way the snout on the holotype skull has an undulating profile kind of like a wave. The tail vertebrae of Sinusonasus are also noteworthy in that the chevrons (the bony projections at the base of the vertebra) are so long in the rear caudal vertebrae, that they would have fitted tightly together forming a plate. This would have stiffened the tail so that it could more easily act as a counterbalance as Sinusonasus was running and manoeuvring after prey. Sinusonasus would have been a predator of smaller animals, with the sickle shaped claws on each foot serving as the main killing weapons.
- A new troodontid (Theropoda: Troodontidae) from the Lower Cretaceous Yixian Formation of western Liaoning, China. - Acta Geologica Sinica 78(1):22-26. - X. Xu & X. Wang - 2004.