Tyrannotitan was discovered in 2005 at La Jaunita farm,near Chubut province, Argentina.It was unearthed Silvina de Valais, Fernando E.Novas, Pat-vickers and Tom Rich. Only part of the teeth, jaw, spine, pelvis and legs were found which means of the animal is a mystery. Fernado named it Tyrannotitan, which meant "Tyrant Titan". This monstrously large theropod has also shed new light on the evolution of later carcharodontosaurids, and how they started to become a bit more tyrannosaurid-like in anatomy.
Even though so little of the animal was found, paleontologists were able to work at that this was a big allosaur, growing to be about 13 meters (43feet) long. Its teeth were thicker than those of its relatives, somewhat similar to those seen in tyrannosaurid dinosaurs, and even had fairly short arms like they do. The spine was curved much like a tyrannosaurid, and its tail was relatively long powerful (some say it was designed for swimming) and likely counter-acted the heavy skull to help keep it balanced and from falling over onto its face. It arguably ranks among the largest of all theropods, coming close to even Tyrannosaurus rex in size, and upper estimates suggest similar or slightly larger size than T. rex, but only in length, not weight. Apart from that, most information about the animal is unknown. However, based upon its close relatives like Giganotosaurus, Mapusaurus, Carcharodontosaurus, and Sauroniops, we can tell that it had a large, probably narrow head that held about 60 teeth in its jaws that were designed to tear through the flesh of its main prey item; sauropods. It also had long, powerful back legs that were probably capable of running up to 20 mph (32 kmph) (or possibly aid it greatly in swimming if proven to be true).