(San Juan lizard).
Named By: Oscar Alcober & Ricardo Martinez - 2010.
Classification: Chordata, Reptilia, Dinosauria, Theropoda, Eusaurischia, Herrerasauridae.
Species: S. gordilloi (type).
Size: Estimated 3 meters long.
Known locations: Argentina, San Juan Province - Ischigualasto Formation.
Time period: Ladinian of the Triassic.
Fossil representation: Partial skeleton with a jaw fragment.
Superficially Sanjuansaurus was probably similar to Herrerasaurus in general appearance, but some skeletal features seem to have been slightly more primitive. Sanjuansaurus lived in the same time and location as its more famous relative Herrerasaurus which would suggest that this form held an important place in their ecosystem. Neither Sanjuansaurus nor Herrerasaurus would have been top predators however as large rauisuchian predators like the seven meter long Saurosuchus dominated the area. Although certainly not as fast as Sanjuansaurus, Saurosuchus had a tough hide with osteoderm armour down its back along with jaws that were larger and much more powerful than Sanjuansaurus.
- A new herrerasaurid (Dinosauria, Saurischia) from the Upper Triassic Ischigualasto Formation of northwestern Argentina. - Zookeys 63:55-81. - O. A. Alcober & R. N. Martínez - 2010.