Siamotyrannus

(A) A phylogenetic principal-component analysis (PCA) represents the projection of the Dinosauria supertree (STAR Methods) into a PCA of climatic variables. PC1 axis shows strong positive correlation with maximum temperature ([temp max), low positive correlation with precipitation seasonality ( precip season), strong negative correlation with minimum temperature (Ytemp min), and strong negative correlation with minimum precipitation (Yprecip min). PC2 axis shows strong positive correlation with minimum temperature ([temp min) and negative correlation with precipitation seasonality (Yprecip season). Shadows around points highlight the relative density in the principal compo- nent space of non-dinosaurian Dinosauromorpha (gray), Ornithischia (blue), Sauropodomorpha (green), and Theropoda (red). (B) Lower left plot shows 95% confidence interval convex hulls for each dinosauromorph subclade. Blue thermometer (top left corner) symbolizes the direction of the vector in the PC space region for cold temper- atures; yellow thermometer (top right corner) indicates the direction of the vector in PC space for warm tem- peratures; brown shrub (top right corner) depicts dry conditions, while the same with a gray, rainy cloud (mid, lower side of the graph) illustrates seasonal conditions. Silhouettes represent the following taxa (clockwise from the higher left corner): Minmi, Edmontosaurus, Pachyrhinosaurus, Tyrannosaurus, Asilisaurus, Graci- liceratops, Harpymimus, Altirhinus, Gobititan, Suz- housaurus, Marasuchus, Pampadromaeus, Herrer- asaurus, Vulcanodon, Diplodocus, Giraffatitan, Coelophysis, Dromomeron, Gondwanatitan, Tapuiasaurus, Anchisaurus, Siamotyrannus, Diodorus, Suchomimus, Phuwiangosaurus, Ouranosaurus, Irritator, Tangvayosaurus, Nanshiungosaurus, Aeolosaurus, Rebbachisaurus, Chuxiongosaurus, Tethyshadros, Koreanosaurus. Genyodectes, Mapusaurus, Vegavis, Goyocephale, and Rhoetosaurus.

Illustration of the pelvis from the theropod dinosaur Siamotyrannus isanensis. Siamotyrannus lived in Thailand, according to scientists about 90 MYA. It has been estimated to a length of 7 meter, and a weight of about 2 tonnes. Scientists has been uncertain if Siamotyrannus is a member of the family Tyrannosauridae or to Sinraptoridae.