Despite not knowing much about the skull of Siats there is enough information in the fossils for researchers like Zanno and Makovicky to know that Siats is a theropod dinosaur. These include the shapes of the pelvis and the known vertebral elements, as one would suspect. Seeing those bones on a table and hearing what they are does not necessarily tell anyone where they are in the body or where they were positioned exactly. For that reason we have skeletal illustrations that we can refer to, such as this one. Additionally, there are elements of the legs and feet, specifically portions of the tibia and individual phalanges belonging to both feet. These are not enough to flesh out the entire feet and tell us exactly what the feet looked like either, but remember, a lot of what Siats looked like comes from its known familial relationships. These relationships are well enough known that the scientific illustrations that have been created using the inferences and knowledge of these dinosaurs are well received and considered accurate.
|From Zanno and Makovicky 2013|