The Spinosaurus ("Thorn Lizard“)
is considered the largest land-grabbing dinosaur that ever lived. The Spinosaurus aegypticus
is the only known species of this genus. The first bones of this dinosaur were discovered in Egypt in 1912 and described by the German paleontologist Ernst Stromer von Reichenbach in 1915.
The distinctive feature of Spinosaurus is the conspicuous spinous processes of the dorsal vertebrae, which grew to at least 1.7 meters in length and were probably connected with skin to form a sail-like structure. Some scientists suggest that the processes were surrounded by muscles and formed an elongated hump. The function of this sail is still unclear. It could be a structure for thermoregulation or communication with conspecifics (e.g., imponation behavior). The snout of Spinosaurus was narrow and equipped with non-toothed conical teeth. At the front end of the upper jaw there were six to seven teeth per side. On the rear end there were another twelve teeth on each side. The teeth of Spinosaurus are straight and pointed.
Another special feature are the nostrils on top of the elongated, flat skull. Similar to a crocodile, Spinosaurus could thus still breathe almost completely submerged. In addition, there were openings for nerve endings at the top of the skull, which could have served as motion sensors in the water, as in crocodiles. In the meantime, it is assumed that Spinosaurus spent most of its time in the water and near the water and also hunted here or specialized in catching fish. Among its prey was the Onchopristis numidis, a saw ray up to 8 meters long. Teeth of Spinosaurus with remains of the sawfish were often found. It is still not completely clear whether it moved on 2 or 4 legs. However, with the latest finds and reconstructions, there is much to suggest that due to the very short hind legs and the immense weight of the sail-like hump, Spinosaurus was on all fours most of the time.
The habitat of Spinosaurus was the north of Africa. It lived together with other dinosaur species such as the Carcharodontosaurus, the Aegyptosaurus, the Bahariasaurus and the gigantic Paralititan in a wet mudflat landscape with mangrove forests.
The most common sites of Spinosaurus are in Egypt, Morocco, Algeria, Tunisia, and Niger.