Meaning: ‘Thorn lizard’ or ‘Spine lizard’
Period: Late Cretaceous (95 – 70 million years ago)
Group: Theropods (beast feet)
Size: It was 18m long and 5m tall. It weighed about 4000kg.
Characteristics: The Spinosaurus walked on two legs and had large bony spines coming out of its back vertebrae to form a sail. It is believed the upper spine was very flexible as the vertebrae consisted of ball-and-socket-joints meaning it could arch its back, perhaps to spread its sail, in a similar fashion to opening a fan. This has led palaeontologists to conclude the sail may have been for regulating body temperature. The sail may have also been used to attract mates or give the appearance it was larger than it was. The sail could have been brightly coloured, like the fins of some reptiles today.
Named by: Ernst Stromer von Reichenbach in 1915
Discovery: Fragmentary remains of the Spinosaurus aegyptiacus were found by Richard Markgraf in 1912, in the Bahariya Formation of western Egypt. These incomplete fossils included bony-sail spines up to 1.8m long. However the partial skeleton was unfortunately destroyed during WWII. A potential second species Spinosaurus maroccanushas has since been recovered from Morocco.