ankylosaur

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ankylosaur

dinosaur infraorder

Also known as: Ankylosauria

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Last updated

June 18, 2026

Quick Summary

Ankylosaurs were a group of herbivorous, four-legged dinosaurs that lived during the Cretaceous Period. They are known for their extensive body armor, consisting of bony plates, spikes, and knobs, which protected them from predators.

The genus Ankylosaurus was one of the largest, reaching up to 33 feet long and weighing about four tons. It had a square, flat head and a long tail that ended in a heavy bone club, likely used as a defensive weapon. Ankylosaurs had simple, leaf-shaped teeth and likely ate soft plant material. While most ankylosaurs shared these traits, some, like the nodosaurs, lacked a tail club and had different armor patterns.123

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dinosaur
Ankylosauria
The ankylosaurs are known from the Late Jurassic and Cretaceous periods. They are called “armoured dinosaurs” for their extensive mosaic of small and large interlocking bony plates that completely encased the back and flanks. Most ankylosaurs, such as Euoplocephalus, Nodosaurus, and
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The ankylosaurs are known from the Late Jurassic and Cretaceous periods. They are called “armoured dinosaurs” for their extensive mosaic of small and large interlocking bony plates that completely encased the back and flanks. Most ankylosaurs, such as Euoplocephalus, Nodosaurus, and
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dinosaur
Reconstruction and classification
…similar herbivores), Stegosauria (plated forms), Ankylosauria (Hylaeosaurus and other armoured forms), and Ceratopsia (horned dinosaurs, just then being discovered in North America). Seeley’s second order, the Saurischia, included all the carnivorous dinosaurs, such as Megalosaurus and Compsognathus, as well as the giant herbivorous sauropods, including
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…similar herbivores), Stegosauria (plated forms), Ankylosauria (Hylaeosaurus and other armoured forms), and Ceratopsia (horned dinosaurs, just then being discovered in North America). Seeley’s second order, the Saurischia, included all the carnivorous dinosaurs, such as Megalosaurus and Compsognathus, as well as the giant herbivorous sauropods, including
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ornithischian
of the Stegosauria and Ankylosauria and their relatives.
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of the Stegosauria and Ankylosauria and their relatives.
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Stegosaurus
…are closely related to the ankylosaurs, with which they share not only dermal armour but several other features, including a simple curved row of small teeth. Both groups evolved from a lineage of smaller armoured dinosaurs such as Scutellosaurus and Scelidosaurus of the Early Jurassic Period (206 million to 180…
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…are closely related to the ankylosaurs, with which they share not only dermal armour but several other features, including a simple curved row of small teeth. Both groups evolved from a lineage of smaller armoured dinosaurs such as Scutellosaurus and Scelidosaurus of the Early Jurassic Period (206 million to 180…
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