The Cretaceous period of the dinosaurs was a time spanning about 50 million years. Here are 25 species (listed alphabetically) from that time period:
Abelisaurus – This Carnivore lived 80 MYA (million years ago), and was indigenous to what is now South America. It is believed to be a cousin of the Aucasaurus, which would make it a two-legged animal. However, the only fossil ever found of this 30-foot beast is merely a partial skull.
Abydosaurus – This herbivore hails from the southwestern region of the United States around Utah. It stood on 4 legs and is believed to have lived around 104 MYA. Abydosaurus was a sauropod, making it a close relative of the gigantic Brachiosaurus.
Acanthopholis – This creature was a herbivore from early Cretaceous years that could grow to be up 18 feet in length and weigh over 300 pounds!. It walked on all fours, and sported heavily armored plates on it’s back, along with large spikes around the neck to ward off predators. It is most closely related to the more popular Stegosaurus.
Achelousaurus – These 4-legged herbivores roamed 74 MYA, in the area that is now Montana, and are closely related to the Triceratops, sporting the same armored face plate and horns on its head. Its name comes from the Greek deity, Achelous, who had one of his horns torn of by Hercules.
Acheroraptor – This cousin of the Velociraptor lived in the very late Cretaceous period (about 66 MYA), and is the youngest species of it’s kind. It supported itself on 2 legs, and was a ferocious hunter.
Achillesaurus – This aptly named creature is named after the Achilles heel, and was one of the fastest land animals of the late Cretaceous time period (85 MYA). It lived on a plant diet, and was discovered in Rio Negro, Argentina.
Achillobator – Discovered in Asia, specifically Mongolia, this species was the largest of the dromaeosaurid theropods, and lived 90 MYA. Closely related to the Velociraptor, it is known for a large, sickle-shaped claw protruding from its second toe.
Acristavus – Hailing from the Campanian stage of the Cretaceous period (79 MYA), this dinosaur is a distant cousin of the Triceratops. It was a herbivore and lived mostly near rivers and flood plains. It was discovered in Utah.
Acrocanthosaurus – One of the largest of the theropods, this fierce hunter is related to the T-rex, and could grow to be almost 40 feet tall! In thrived in the early Cretaceous time period (110 MYA), and fossils have been found in many parts of North America.
Acrotholus – This mysterious plant eater was a native of what is now Canada, and lived 84 MYA. It was known for its dome-shaped head. Little is known about this species, although it was one of the oldest of its classification (pachycephalosaurid).
Adamantisaurus – Although the exact time period for this animal is unknown, it is widely debated that it lived about 93 MYA, placing it during the late Cretaceous period. It was likely a very large animal, with a very long neck, and an equally long tail. It got around on 2 legs, and was a fast runner.
Adasaurus – This small carnivore is a relative of the Velociraptor, and is believed to have roamed the plains of Asia around 65 MYA (late Cretaceous). It hunted using a sharp, curved claw that extended from the second toe on each foot.
Adelolophus – This species is the only one of its kind, and lived late in the Cretaceous period (almost 80 MYA). It was known for its duck-like bill, which leads scientists to believe that it lived off of plant life.
Aegyptosaurus – This species comes from Africa, and lived in the mid and late Cretaceous era. Scientists put its existence at roughly 93 MYA. This dinosaur was small, and was easy prey for larger species. Most of the fossils for the Aegyptosaurus were destroyed in 1944.
Aeolosaurus – This gigantic herbivore was a close relative of the Brontosaurus, and lived approximately 80 MYA in South America. With its long neck and tail, this species is believed to have grown to be 50 feet in length!
Aepisaurus – Very little is known about this species, as the only fossil ever found of it was a single humerus bone, and was lost year ago. It is believed to have lived about 100 MYA, and to be related to the crocodile.
Aerosteon – This 30 foot long meat-eater is related to the T-rex, and lived in the region of Argentina around 83 MYA. After piecing together the only fossils discovered from this creature, it was determined that they were that of a younger Aerosteon, so an adult specimen has never been found.
Agathaumas – This species is loosely related to the Triceratops, and lived approximately 66 MYA in the area that is now Wyoming. It could grow to be 30 feet long on all fours, and was the largest land animal known at that particular time.
Agujaceratops – Another dinosaur from the late Cretaceous period (about 77 MYA), the Agujaceratops is related to the Triceratops, and the two look virtually identical. Like its more popular relative, this animal had 4 legs and was a herbivore.
Agustinia – This dinosaur from around 108 MYA looked fierce, with a line of sharp spikes running down it’s back, but scientists concluded that it was most likely an omnivore that shared characteristics with the Stegosaurus. It walked on all fours, and could be found near lakes and streams.
Ahshislepelta – This species from New Mexico closely resembles the Ankylosaur, widely known for it’s heavily plated armor. It is not determined how old this dinosaur is, but it has been placed in the late Cretaceous time period.
Airakoraptor – Another mysterious species, scientists have not been able to determine exactly when this dinosaur lived, just that it was in the Cretaceous period and in Mongolia. It’s characteristics are similar to the Velociraptor.
Ajancingenia – This dinosaur lived about 70 MYA in the Mongolian region and is related to the Velociraptor. It was an avid hunter, and was known to travel large distances during the course of its life.
Ajkaceratops – A cousin of the Triceratops, this animal lived in Hungary around 86 MYA. While it didn’t sport horns, it had a powerful beak and face plate to protect itself, and was a herbivore.
Alamosaurus – This enormous relative of the Brontosaurus was also a herbivore that lived in southern North America 66 MYA. It walked on on fours and could be over 50 feet in length!