- Abelisaurus
- Classification
- Theropods
- Characteristics
- Carnivorous
- Era
- Cretaceous period
- Afrovenator
- Classification
- Theropods
- Characteristics
- Carnivorous
- Era
- Jurassic 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
- Allosaurus
- Classification
- Theropods
- Characteristics
- Carnivorous
- Era
- Jurassic period
- Alvarezsaurus
- Classification
- Theropods
- Characteristics
- Carnivorous
- Era
- Cretaceous period
- Alwalkeria
- Classification
- Theropods
- Characteristics
- Carnivorous
- Herbivorous
- Omnivorous
- Era
- Triassic period
- Amargasaurus
- Classification
- Sauropods
- Characteristics
- Herbivorous
- Era
- Cretaceous period
- Anchisaurus
- Classification
- Sauropods
- Characteristics
- Herbivorous
- Era
- Jurassic period
- Ankylosaurus
- Classification
- Thyreophora
- Characteristics
- Herbivorous
- Era
- Cretaceous period