Spinosaurus (meaning "spined lizard") is an extinct genus of spinosaurid theropod dinosaur that existed in what is now North Africa during the Cretaceous period. Spinosaurus is argued to have the longest jaw and tail of all known carnivorous dinosaurs, even longer than Carcharodontosaurus, Giganotosaurus, and Tyrannosaurus rex. It is also the largest species of spinosaurid, Despite not sharing the robust build of these earlier species, estimates published in 2005, 2007, and 2008 suggest that it was 12.6 to 18 meters long and weighed 7 to 20.9 tons. But new estimates published in 2014 and 2018, based on a more complete specimen, backed up the previous research and found that Spinosaurus could have reached lengths of 13 to 15 meters. The latest estimates suggest a weight of 6.4 to 7.5 tons.