Dinosaurs are renowned not only for their size but also for their diverse adaptations. Think of T. rex‘s huge jaws capable of more than 10,000 newtons of pressure or Triceratops who had the largest head of any known land animal. Among these, some species stand out for their impressive armor.

These creatures evolved various forms of protection, including bony plates, spikes, and tail clubs to deter predators. Here’s a rundown of some of the tankiest dinosaurs.

1. Ankylosaurus: “Fused Lizard”

Ankylosaurus was a heavily armored dinosaur, reaching up to 8 meters long and weighing between 5.3 to 8.8 tons. Its body was broad, low, and supported by four sturdy legs​. Its head was wide and flat, with two pairs of backwards-pointing horns and a beak-like mouth with small, leaf-shaped teeth​​​.

Ankylosaurus body was covered in thick, bony plates called osteoderms, which were embedded in its skin and provided protection from predators. It also had a large club at the end of its tail, composed of fused vertebrae, which it could swing with great force to defend itself. This tail club could potentially break the bones of attacking predators.

Ankylosaurus was a herbivore, feeding on low-lying plants like ferns and cycads. It lived during the Late Cretaceous period, about 70 to 66 million years ago, in modern-day North America. Despite its heavy armor and slow movement, Ankylosaurus was well-adapted to its environment, using its strong sense of smell to locate food and avoid predators​ like Tyrannosaurus rex​.

2. Stegosaurus: “Roof Lizard”

We all know and love them. Stegosaurus was a large, heavily built dinosaur, typically measuring around 9 meters long and weighing around 5.5 tons. The most notable features of Stegosaurus are its bony plates and tail spikes. The plates, which could be over two feet tall, likely served several functions, including display for species recognition, attracting mates, and possibly thermoregulation. The thagomizers were used for defense and could deliver powerful blows to predators, as evidenced by damage found on some spikes and corresponding injuries on Allosaurus fossils​.

Stegosaurus lived during the Late Jurassic period, approximately 159 to 144 million years ago, in what is now North America and Portugal. It was an herbivore, feeding on low-lying plants such as ferns, mosses, cycads, and shrubs. Its small, narrow head and weak bite force indicate it likely consumed soft vegetation. Stegosaurus may have traveled in herds, providing protection through numbers and utilizing its tail spikes for defense​​.

3. Nodosaurus: “Knobbed Lizard”

Nodosaurus, the name bearer for its family, was a medium-sized nodosaurid, measuring around 6 meters long and weighing around 3.5 tons. It had a broad, heavily armored body covered in bony plates and spikes, but lacked a tail club. These plates were arranged systematically across its body, with some areas featuring additional backward-curved spikes or knobs. This extensive armor made Nodosaurus a difficult target for any would-be predator. Its head was small and narrow with a toothless beak and grinding teeth at the back of its mouth​.

Nodosaurus lived during the Late Cretaceous period, around 113 to 98 million years ago, primarily in what is now Wyoming and Kansas. As a herbivore, it fed on low-lying vegetation such as ferns, cycads, and conifers. Its heavy armor and slow movement suggest it relied on its defensive features rather than speed to evade predators​.

4. Euoplocephalus: “Well-Armored Head”

Euoplocephalus was a large ankylosaurid, measuring around 6 meters long and weighing about 2.5 tons. It had a broad, flat skull and was heavily protected by bony plates and spikes covering its back, sides, and even its eyelids​​. Its back, head, and sides were covered in bony plates called osteoderms, providing excellent protection against predators. It also had a prominent club at the end of its tail, which could deliver powerful blows to deter attackers.

Euoplocephalus lived during the Late Cretaceous period, approximately 99 to 65 million years ago, in what is now North America, particularly in Alberta, Canada. It was a herbivore, feeding on low-lying plants. Euoplocephalus likely foraged near ground level, using its beak to strip leaves and its teeth to grind plant material. It might have lived in small herds, providing mutual protection through numbers and communication via vocalizations and body language​​.

5. Saichania: “Beautiful One”

You probably figured by now that this list would be full of ankylosaurs. Saichania was another ankylosaurid measuring between 5 to 7 meters long and weighing approximately 1.4 to 2 tons. It had a wide, flat body covered in bony plates, with a broad, heavily armored skull and a clubbed tail​. Osteoderms covered Saichania’s entire body, which included spikes and a bony cap on its head. The tail club, composed of fused vertebrae and covered in large bony knobs, was a powerful defensive weapon. Its skull featured complex air passages that may have helped regulate temperature and conserve water in its arid environment​.

Saichania lived during the Late Cretaceous period, around 80 million years ago, in what is now Mongolia and China. It thrived in hot, desert-like environments and was a herbivore, feeding on tough, fibrous plants. Its short, stout legs and heavy armor suggest it was slow-moving but well-equipped to defend itself against predators like Tarbosaurus​​.

6. Polacanthus: “Many Thorns”

Polacanthus was a medium-sized nodosaur, approximately 5 meters long and weighing around 2 tons. It had a broad, heavily armored body with a small head, beak-like mouth, and stout limbs. Its armor consisted of bony plates and spikes that covered its back, sides, and tail​. It grew rows of long, conical spines along its trunk and tall and more flattened triangular spines on its neck and shoulders. A large, flat rectangular dermal shield covered its hips and the base of its tail, which ended in a mass of fused bony plates​.

Polacanthus lived during the Early Cretaceous period, around 130 to 125 million years ago, in what is now Europe, particularly the Isle of Wight and Sussex in England. As a herbivore, it fed on tough vegetation such as ferns and cycads.

7. Edmontonia

Polacanthus‘ slightly larger cousin, Edmontonia was a 6.6 meters long and 2 meters tall nodosaurid. Weighing around 3 tons, its body was broad and low-slung, covered in bony plates and spikes. The head was relatively small compared to its body, with a beak-like mouth​​. This dinosaur was heavily armored, with osteoderms forming a dense layer of protection over its back and sides. Its most distinctive feature was large, forward-pointing shoulder spikes, likely used in defense and display. As a nodosaur, the genus lacked a tail club but had a flexible tail​​.

Edmontonia lived during the Late Cretaceous period, about 75 to 65 million years ago, in modern-day Alberta, Canada, and parts of the United States. It was a herbivore, feeding on low-growing plants. Its robust armor and spikes made it well-suited for deterring the large tyrannosaurs it shared habitats with, like Albertosaurus and Daspletosaurus​.

8. Borealopelta: “Northern Shield”

Borealopelta is one of the most notable nodosaurids, measuring around 5.5 meters long and weighing approximately 1.5 tons. It had a robust, low-slung body covered in thick bony armor, including large shoulder spikes and a wide, heavily armored head​. Additionally, Borealopelta exhibited counter-shading camouflage, suggesting that it was still under predator threat despite its armor.

This dinosaur is remarkable due to a well-preserved specimen discovered in 2011 at the Suncor Millennium Mine in Alberta. This fossil is one of the best-preserved dinosaur specimens ever found, with its armor, skin, and even stomach contents intact. The exceptional preservation has provided unparalleled insights into the dinosaur’s diet, behavior, environment, and color​.

Borealopelta lived during the Early Cretaceous period, about 110 million years ago, in today’s Alberta, Canada. It was a herbivore, feeding primarily on ferns, as indicated by the analysis of its fossilized stomach contents. These contents also included mosses, conifers, and charcoal, suggesting that Borealopelta foraged in areas that experienced recent wildfires, taking advantage of the new growth. This dinosaur likely roamed coastal plains and forested regions, using its armor and spikes to protect itself from predators​.

9. Tarchia: “Brainy One”

Tarchia was a large ankylosaurid dinosaur, measuring about 5 to 6 meters long and weighing around 3 tons. It had a broad, low-slung body supported by strong, short legs. The dinosaur’s body was heavily armored with thick, bony plates covering its back, and neck, and sporting a tail club​. The name “Tarchia” means “brainy one,” reflecting its relatively large braincase compared to other ankylosaurids. This larger braincase may have provided Tarchia with slightly enhanced cognitive abilities, though it was still quite limited by modern standards. The armor consisted of osteoderms that fused to its vertebrae, offering substantial protection​.

Tarchia lived during the Late Cretaceous period, around 70 million years ago, in what is now Mongolia, particularly in the Nemegt and Barun Goyot formations. It was a herbivore, feeding on low-growing vegetation. The dinosaur’s broad, beak-like mouth and teeth were particularly adapted for grinding tough plant material. Tarchia likely moved slowly due to its heavy armor but compensated with its powerful tail for defense​​.

10. Scelidosaurus: “Limb Lizard”

Scelidosaurus was a medium-sized dinosaur, measuring about 4 meters long and weighing around 300 kilograms. Its body was low-slung and supported by four sturdy legs, with hind limbs longer than the forelimbs. The head was small and elongated, featuring a beak-like mouth and numerous teeth suitable for a herbivorous diet​.

This special dinosaur was heavily armored, with bony plates and spikes covering its back and sides. It also had large spines on its shoulders and a tail with bony rings, possibly used for defense rather than display. The armor was made up of osteoderms embedded in the skin, arranged in horizontal rows along the body​​.

Scelidosaurus lived during the Early Jurassic period, about 191 million years ago, primarily in what is now England. It was a herbivore, feeding on low-growing vegetation such as ferns and cycads. Its teeth and jaw structure suggest it could grind tough, fibrous plants. I mentioned Scelidosaurus as being special for it is one of the earliest-known ornithischian dinosaurs. Moreover, it is widely speculated that the genus is a common ancestor of the Stegosauridae, Nodosauridae, and Ankylosauridae families, thus making it the grand-grand-grandfather of every genus on this list​.

11. Minmi

Like its name suggests, Minmi was a small and cute ankylosaur, measuring about 3 meters long and weighing anywhere between 300 to 600 kilograms. It had a low, broad body with relatively long legs for an ankylosaur, allowing it to move more quickly than its heavily armored relatives. Its head was small and narrow, featuring a beak-like mouth​​.

Minmi’s most distinctive feature was its unique armor. It had horizontal bony plates (ossified tendons) along its spine, providing muscle attachment points that enhanced mobility. It also had a series of bony plates and spikes covering its body, offering some protection against predators. Unlike many of its ankylosaurid relatives, Minmi had no tail club​.

Minmi lived during the Early Cretaceous period, around 120 to 112 million years ago, in what is now Queensland, Australia. It inhabited floodplains and woodlands, feeding on low-growing vegetation.

12. Zuul: “The Shin Destroyer”

Zuul was a medium-sized ankylosaurid dinosaur, measuring around 6 meters in length and weighing around 3 tons. It had a wide, short snout, prominent horns behind its eyes, and a heavily armored body with a distinctive tail club​​. Besides its large club, the tail was also adorned with rows of sharp, bony spikes. These features suggest that Zuul could deliver powerful blows to predators or rivals and earned it the moniker “The Shin Destroyer“. The preservation of Zuul’s skeleton includes soft tissue and skin impressions, providing detailed insights into its physical appearance and armor configuration​. Furthermore, fossilized individuals with smashed and healed osteoderms in the pelvic area suggest they often engaged in battle with one another.

Zuul lived during the Late Cretaceous period, around 75 million years ago, in what is now Montana. The heavily armored body and devastating tail were essential for protection against large predators like tyrannosaurs.

13. Kentrosaurus

Kentrosaurus was a medium-sized stegosaurid, measuring around 5 meters long and weighing approximately one ton. It had a small, elongated head with a beak-like mouth and cheek teeth adapted for processing plant material. The body was heavily built, supported by robust forelimbs and powerful hind limbs​. Kentrosaurus’ most distinctive features were its bony plates transitioning to spikes towards its tail. These large, sharp spikes on its tail and shoulders could reach up to 72 centimeters long. This armor may have also played roles in thermoregulation and display​.

Kentrosaurus lived during the Late Jurassic, approximately 155 to 150 million years ago, in what is now Tanzania. It inhabited lush, forested areas with abundant coniferous trees, ferns, and cycads. The structure of its limbs suggests that it could rear up on its hind legs to reach higher vegetation. Fossil evidence indicates that Kentrosaurus likely lived in herds, providing protection against predators like Allosaurus through group defense mechanisms​.