Spinosaurus aegyptiacus SPINE-oh-SOR-us
"Spine lizard"
You 1.8 m (5.9 ft) tall
Spinosaurus 15 m (49 ft) long
9 people holding hands
- Length
- 15 m (49 ft) — About 15 m long, ~7 tonnes — the longest theropod known.
- Period
- Late Cretaceous (99–93 Mya)
- Place
- Africa · Morocco · Egypt
- Food
- Piscivore (fish-eater) — Mostly fish — including giant sawfish and lungfish from North African rivers.
Spinosaurus is the strangest theropod ever found. Long crocodile-shaped jaws, a giant sail down its back, short hind legs, paddle-like tail — almost everything about it points to a life spent in the water. The original skeleton was destroyed in WWII, and for decades artists had to guess what it looked like. New finds in Morocco rewrote almost everything in the 2010s.
What we know
- Long, narrow, crocodile-like jaws full of conical teeth — built for catching fish.
- Tall neural spines on the back formed a sail nearly 2 m tall.
- Tail had tall fin-like neural spines, suggesting use as a propulsive paddle.
- Original skeleton destroyed in the 1944 Munich bombing; later finds restored knowledge.
What we guess
- How much time it spent in water vs. on land. 2014 and 2020 studies argue for semi-aquatic life; some 2022 work pushes back.
- What the sail was for — display, heat regulation, sexual selection, or all three.
- Whether it swam mainly by tail propulsion or by punting along the bottom.