Ankylosaurus ("Fused lizard") is a genus of ankylosaurid dinosaur found in geologic formations dating to the very end of the Cretaceous Period in western North America. Although a complete skeleton has not been discovered and several other dinosaurs are represented by more extensive fossil material, Ankylosaurus is often considered the archetypal armored dinosaur. Other ankylosaurids shared its well-known features, like the heavily-armored body and massive bony tail club, but Ankylosaurus was the largest member of its family. In comparison with modern land animals the adult Ankylosaurus was very large. Some scientists have estimated a length of 9 meters (30 ft).[1] Another reconstruction suggests a significantly smaller size, at 6.25 m (20.5 ft) long, up to 1.5 m (5 ft) wide and about 1.7 m (5.5 ft) high at the hip. Ankylosaurus may have weighed over 6,000 kilograms (13,000 lb). The body shape was low-slung and quite wide. Ankylosaurus was quadrupedal, with the hind limbs longer than the forelimbs. Ankylosaurus was herbivorous, with small, leaf-shaped teeth suitable for cropping vegetation.

Edmontonia was an armoured dinosaur, a part of the nodosaur family from the Late Cretaceous Period. It is named after the Edmonton Formation (now the Horseshoe Canyon Formation), the unit of rock it was found in. Edmontonia was bulky and tank-like at roughly 6.6 m (22 ft) long and 2m (6 ft) high. It had small, ridged bony plates on its back and head and many sharp spikes along its back and tail. The four largest spikes jutted out from the shoulders on each side, two of which were split into subspines in some specimens. Its skull had a pear-like shape when viewed from above.

Euoplocephalus ("Well-armored head") was one of the largest genera of ankylosaurian dinosaurs, at about the size of a small elephant. It is also the ankylosaurian with the best fossil record, so its extensive spiked armor, low-slung body, and great club-like tail are well documented. Genera that are thought to be the same as Euoplocephalus include Scolosaurus, Anodontosaurus, and Dyoplosaurus. Among the ankylosaurids, Euoplocephalus was exceeded in size only by Tarchia and Ankylosaurus. Euoplocephalus was 6 metres (20 ft) long and weighed about 2 tonnes (2.2 short tons). While it was 2.4 metres (7.9 ft) wide, it was low-slung, with short, stout legs. The rear legs were larger than the front legs and all four limbs were tipped with hoof-like claws. Like all ankylosaurids, it had a flat, thick, triangular skull. The mouth included a horny beak and the teeth were small and roughly leaf-shaped. It had a short neck.

Gargoyleosaurus ("Gargoyle lizard") is both the smallest and the earliest well-known ankylosaur. Its skull measures only 29 centimetres (11 in) in length, and its total body length is an estimated 3 to 4 metres (9.8 to 13 ft). It may have weighed as much as 1 tonne (2,200 lb).

Gastonia is a genus of polacanthine ankylosaurid dinosaur from the Early Cretaceous of North America, around 125 million years ago. Closely related to Polacanthus, it has a sacral shield and large shoulder spikes. It is also the first polacanthine dinosaur to have been mounted for display at the Denver Museum of Nature and Science, together with the related Gargoyleosaurus. This dinosaur was found in the same quarry as Utahraptor.

Hesperosaurus ("Western lizard") was a herbivorous dinosaur from the Jurassic period (approximately 150 million years ago), whose fossils are found in the state of Wyoming in the United States of America. Hesperosaurus was a type of stegosaurid, having alternating plates on its back and four spikes on its tail. The plates on its back were not as tall, but were longer, than in its cousin Stegosaurus. It had a shorter, broader skull than Stegosaurus and appears most closely related to Dacentrurus.

Huayangosaurus is a genus of stegosaurian dinosaur from the Middle Jurassic of China around 165 million years ago, some 20 million years before its famous relative, Stegosaurus appeared in North America. Like other stegosaurians, Huayangosaurus was a quadrupedal herbivore with a small skull and a spiked tail. Like its more famous relative, Stegosaurus, Huayangosaurus bore the distinctive double row of plates that characterize all the stegosaurians. These plates rose vertically along its arched back. In Huayangosaurus, the plates were more spike-like than in Stegosaurus. Like Stegosaurus, however, it bore two pairs of long spikes extending horizontally near the end of its tail. Huayangosaurus was one of the smallest known stegosaurians, at just 4.5 meters in length.

Kentrosaurus ("Pointed lizard") is a genus of stegosaurid dinosaur from the Late Jurassic of Tanzania, related to the better-known Stegosaurus of North America. This 4 meter long stegosaurian was described by Edwin Hennig in 1915. Like Stegosaurus, Kentrosaurus had a double row of plates running down its spine. The two differed in size, in the shape of their armour plating, and in their bodily flexibility, however. The bony plates gave way to spikes about mid-way along the spine. It also had spikes on its flanks.

Minmi, named for Minmi Crossing, Australia (where it was found), is a genus of small ankylosaurian dinosaur that lived during the early Cretaceous Period, about 119 to 113 million years ago. Minmi had four long (for an ankylosaurian) legs, with hind legs that were larger than front legs, a short neck and a wide skull with a very small brain. The dinosaur grew to about 2 m (6.6 ft) long and was roughly 1 m (3 ft) tall to the top of the shoulder. Minmi probably moved relatively slowly on four legs, as determined by scientists from fossilized tracks, its estimated mass and its leg length.