Sigilmassasaurus

Sigilmassasaurus is a controversial genus of carnivorous theropod dinosaur from the Late Cretaceous of Africa. Its name means ''Sijilmassa lizard", referring to the name of the city near the place where its fossils were found.

Its species name "brevicollis" is Latin for "short neck", because the neck bones of the animal are very short. It may be a synonym or developmental variation of Spinosaurus, the largest theropod to have ever lived.

Sigilmassasaurus was found and named by a Canadian paleontologist called Dale Russel. In 1996, he found fossils in Morocco at a site called the Kem Kem Formation. The skeleton was found in rocks that were as old as the Cenomanian. This was the earliest stage of the Late Cretaceous Period, which occurred 100 million to 94 million years ago.^[1]

Paleontologists know that several large predatory dinosaurs weighing more than one tonne lived in North Africa during the Late Cretaceous Period. This made paleontologists wonder how so many of them would have lived together. Sigilmassasaurus existed in the same time and place as other huge meat-eating dinosaurs like Spinosaurus, Carcharodontosaurus, Deltadromeus, and Bahariasaurus.

Similarly, during the Late Jurassic Morrison Formation in North America, there were up to five meat-eating dinosaurs weighing more than a tonne, as well as many smaller ones. The difference between their sizes and what they ate could explain why they could live so close to each other. Scientists have compared this to how predatory animals live alongside each other in the African savanna.^[1]