! Name !! Period !! Diet !! Notes |- | Abrosaurus || Jurassic || herbivore || Small Camarasaurus–like sauropod |- | Achillobator || Cretaceous || carnivore || — |- | Adasaurus || Cretaceous || carnivore || — |- | Agilisaurus || Jurassic || herbivore || — |- style = "background-color: #88bbbb; color:#ffe" | Airakoraptor || Cretaceous || carnivore || — |- | Albalophosaurus || Cretaceous || herbivore || — |- | Albinykus || Cretaceous || carnivore || — |- | Alectrosaurus || Cretaceous || carnivore || — |- | Alioramus || Cretaceous || carnivore || — |- | Altirhinus || Cretaceous || herbivore || — |- | Alxasaurus || Cretaceous || herbivore || — |- | Amtocephale || Cretaceous || herbivore || — |- | Amtosaurus || Cretaceous || herbivore || Based only on fragments of skull |- | Amurosaurus || Creta