Imagine a dinosaur covered in bony plates… but with two gigantic spines protruding from its shoulders like true defensive spears. This was the Gigantspinosaurus, a Stegosaurus as rare as it is fascinating, which lived in what is today China over 150 million years ago, during the Late Jurassic.

Gigantspinosaurus
Family
Ornithischians
Era
Upper Jurassic
Where he lived?
China
Weight
700Kg
Height
1,6m
Length
4m to 7m
A Surprising Fossil: Discovery and Classification
The first remains of Gigantspinosaurus sichuanensis were discovered in 1985 near Jinquan, in Sichuan Province (China), and were initially thought to belong to Tuojiangosaurus. However, in 1992 paleontologist Ouyang Hui recognized that it was a new and unusual species.
It is considered an intermediate basal Stegosaur, with features both primitive and modern within the group. It shares a family with others like Stegosaurus, though with notable differences, as we will see below.
Physical Characteristics: Much More Than Spines
- Impressive Size: the Gigantspinosaurus measured between 4.2 and 7.7 meters in length and weighed around 700 kg.
- Parascapular Spines: its hallmark. These enormous structures protruded from its shoulders, doubling the length of its scapulae. There is no other known dinosaur that had them so developed.
- Dorsal Plates: were relatively small, triangular, and arranged in two rows along the back, unlike Stegosaurus, which had larger and more prominent plates.
- Head and Teeth: it had a larger head than usual for Stegosaurs and about 30 teeth per side in the lower jaw, adapted to a herbivorous diet.
- Textured Skin: skin impressions have been found showing rosette-shaped scales, with a central hexagonal scale surrounded by smaller ones.
Diet and Lifestyle
The Gigantspinosaurus was a quadrupedal herbivore that fed on low vegetation: ferns, cycads, and other prehistoric plants. Its teeth were designed to slice and chew fibrous plant material.
It was likely a relatively slow dinosaur and used its large shoulder spine as its main form of defense, as it did not possess an armed tail like its cousin, Stegosaurus.
Interesting Facts about the Gigantspinosaurus
- It was initially confused with another more well-known stegosaur.
- Its parascapular spines are unique among known dinosaurs.
- Very well-preserved remains have been found, including skin impressions.
- Its dorsal plates were smaller than those of other stegosaurs, and were likely more decorative than defensive.
Comparisons and Context
Did you know that the Gigantspinosaurus was not as large as the Stegosaurus, but its shoulder spines made it appear even more menacing? While the Stegosaurus relied on its spiked tail for defense, the Gigantspinosaurus carried its “weapon” right above its front legs.
The Stegosaur with Luxury Armament
The Gigantspinosaurus is an impressive example of the diversity of evolutionary defenses among stegosaurs. With its huge spines, sturdy body, and distinctive dorsal plates, this dinosaur represents a blend of strength, strangeness, and elegance.
At Dinosaurland, we continue to marvel at such unique creatures. We invite you to learn more about it in our exhibits, where science and adventure come together to bring you prehistory in one step.
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