Spinosaurus is a large theropod dinosaur with a body length comparable to that of Tyrannosaurus Rex and Southern Megalosaurus. There is currently only one valid species in the genus Spinosaurus, namely the Egyptian Spinosaurus, named by German paleontologist Stromer in 1915. Due to its unique appearance and massive size, Spinosaurus has received no less attention than Tyrannosaurus rex. Unfortunately, the holotype specimen of Spinosaurus was destroyed during World War II. For a long time, paleontologists' understanding of Spinosaurus has only been limited to photos of holotype specimens and a few fossil fragments. With the gradual increase of fossil evidence in recent years, the true image of Spinosaurus has emerged.

Jilong is a medium-sized spinosaurus, whose fossils were discovered in Brazil during the Early Cretaceous period. At present, there is only one species under the genus Jilong, which is the type species Chalinjie Jilong. Fossil materials of Jilong are also very rare, but what is slightly better than other similar specimens is that the holotype specimen of Jilong is a well preserved skull. Although the snout is missing, the latter half of the mouth and skull are preserved, which can provide more information for phylogenetic analysis and other research.