what type of organism was this?
It is a genus of coelurosaurian theropod dinosaur, one of the most well-represented of the large theropods
Tyrannosaurus
Tyrannosaurus is a genus of coelurosaurian theropod dinosaur. The species Tyrannosaurus rex ("rex" meaning "king" in Latin), often called T. rex or colloquially T-Rex, is one of the most well-represented of the large theropods.
what time period did the t rex live in Maastrichtian age of the upper Cretaceous period, 68 to 66 million years ago
wiki:19588867
Tyrannosaurus [SEP] Introduction
Tyrannosaurus is a genus of coelurosaurian theropod dinosaur. The species Tyrannosaurus rex ("rex" meaning "king" in Latin), often called T. rex or colloquially T-Rex, is one of the most well-represented of the large theropods. "Tyrannosaurus" lived throughout what is now western North America, on what was then an island continent known as Laramidia. "Tyrannosaurus" had a much wider range than other tyrannosaurids. Fossils are found in a variety of rock formations dating to the Maastrichtian age of the upper Cretaceous period, 68 to 66 million years ago. It was the last known member of the tyrannosaurids, and among the last non-avian dinosaurs to exist before the Cretaceous–Paleogene extinction event.