Spinosaurus and Sigilmassasaurus. Art by Sergey Krasovskiy. Spinosaurus is a genus of theropod dinosaur that lived in what now is North Africa, during the upper Albian to upper Turonian stages of the Cretaceous period, about 112 to 93.5 million years ago. Sigilmassasaurus is a genus of tetanuran theropod dinosaur that lived approximately 100 to 94 million years ago during the middle of the Cretaceous Period in what is now northern Africa.