- Abelisaurus
- Classification
- Theropods
- Characteristics
- Carnivorous
- Era
- Cretaceous period
- Agustinia
- Classification
- Sauropods
- Characteristics
- Herbivorous
- Era
- Cretaceous period
- Ajancingenia
- Classification
- Theropods
- Characteristics
- Carnivorous
- Herbivorous
- Omnivorous
- Era
- Cretaceous period
- Albertaceratops
- Classification
- Marginocephalia
- Characteristics
- Herbivorous
- Era
- Cretaceous period
- Albertosaurus
- Classification
- Theropods
- Characteristics
- Carnivorous
- Era
- Cretaceous period
- Alvarezsaurus
- Classification
- Theropods
- Characteristics
- Carnivorous
- Era
- Cretaceous period
- Amargasaurus
- Classification
- Sauropods
- Characteristics
- Herbivorous
- Era
- Cretaceous period
- Ankylosaurus
- Classification
- Thyreophora
- Characteristics
- Herbivorous
- Era
- Cretaceous period
- Antarctopelta
- Classification
- Thyreophora
- Characteristics
- Herbivorous
- Era
- Cretaceous period
- Argentinosaurus
- Classification
- Sauropods
- Characteristics
- Herbivorous
- Era
- Cretaceous period
- Atlascopcosaurus
- Classification
- Ornithopoda
- Characteristics
- Herbivorous
- Era
- Cretaceous period
- Avimimus
- Classification
- Theropods
- Characteristics
- Carnivorous
- Omnivorous
- Feathered
- Era
- Cretaceous period