page_title: List of dinosaur genera
section_title: A
hierarchical_section_title: List of dinosaur genera / A
caption_attribution_description: Allosaurus fragilis skeleton mounted in the lobby of the San Diego Natural History Museum. Digital picture taken by me in May of 2006. Image is unconditionally released into the public domain.
context_page_description: Dinosaurs are a diverse group of reptiles of the clade Dinosauria. They first appeared during the Triassic period, between 243 and 233.23 million years ago, although the exact origin and timing of the evolution of dinosaurs is the subject of active research. They became the dominant terrestrial vertebrates after the Triassic–Jurassic extinction event 201.3 million years ago; their dominance continued throughout the Jurassic and Cretaceous periods. The fossil record demonstrates that birds are modern feathered dinosaurs, having evolved from earlier theropods during the Late Jurassic epoch. As such, birds were the only dinosaur lineage to survive the Cretaceous–Paleogene extinction event approximately 66 million years ago. Dinosaurs can therefore be divided into avian dinosaurs, or birds; and non-avian dinosaurs, which are all dinosaurs other than birds.
  This list of dinosaurs is a comprehensive listing of all genera that have ever been considered to be non-avian dinosaurs, but this list also includes some dinosaurs which are disputed to be either avian or non-avian, as well as purely vernacular terms.
context_section_description: Aachenosaurus – a piece of petrified wood
  Aardonyx
  "Abdallahsaurus" – nomen nudum, probably Giraffatitan
  Abdarainurus
  Abelisaurus
  Abrictosaurus
  Abrosaurus
  Abydosaurus
  Acantholipan
  Acanthopholis
  Achelousaurus
  Acheroraptor
  Achillesaurus — possible junior synonym of Alvarezsaurus
  Achillobator
  Acristavus
  Acrocanthosaurus
  Acrotholus
  Actiosaurus – a choristoderan
  Adamantisaurus
  Adasaurus
  Adelolophus
  Adeopapposaurus
  Adratiklit
  Adynomosaurus
  Aegyptosaurus
  Aeolosaurus
  Aepisaurus
  Aepyornithomimus
  Aerosteon
  Aetonyx – possible junior synonym of Massospondylus
  Afromimus
  Afrovenator
  Agathaumas - possible synonym of Triceratops
  Aggiosaurus – a metriorhynchid crocodilian
  Agilisaurus
  Agnosphitys - a silesaurid dinosauromorph
  Agrosaurus – probably a junior synonym of Thecodontosaurus
  Agujaceratops
  Agustinia
  Ahshislepelta
  "Airakoraptor" - nomen nudum
  Ajancingenia - synonym of Heyuannia
  Ajkaceratops
  Akainacephalus
  Alamosaurus
  Alaskacephale
  Albalophosaurus
  Albertaceratops
  Albertadromeus
  Albertavenator
  Albertonykus
  Albertosaurus
  Albinykus
  Albisaurus – a non-dinosaurian reptile
  Alcovasaurus
  Alectrosaurus
  Aletopelta
  Algoasaurus
  Alioramus
  Aliwalia – junior synonym of Eucnemesaurus
  Allosaurus
  Almas
  Alnashetri
  Alocodon
  Altirhinus
  Altispinax
  Alvarezsaurus
  Alwalkeria
  Alxasaurus
  Amanzia
  Amargasaurus
  "Amargastegos" - nomen nudum
  Amargatitanis
  Amazonsaurus
  Ambopteryx
  Ammosaurus - junior synonym of Anchisaurus
  Ampelosaurus
  Amphicoelias
  "Amphicoelicaudia" – nomen nudum; possibly Huabeisaurus
  Amphisaurus – preoccupied name, now known as Anchisaurus
  Amtocephale
  Amtosaurus – possibly Talarurus
  Amurosaurus
  Amygdalodon
  Anabisetia
  Analong
  Anasazisaurus
  Anatosaurus – junior synonym of Edmontosaurus
  Anatotitan – junior synonym of Edmontosaurus
  Anchiceratops
  Anchiornis
  Anchisaurus
  Andesaurus
  "Andhrasaurus" - nomen nudum
  Angaturama – probable junior synonym of Irritator
  "Angloposeidon" – nomen nudum
  Angolatitan
  Angulomastacator
  Anhuilong
  Aniksosaurus
  Animantarx
  Ankistrodon – a proterosuchid archosauriform
  Ankylosaurus
  Anodontosaurus
  Anomalipes
  Anoplosaurus
  Anserimimus
  Antarctopelta
  Antarctosaurus
  Antetonitrus
  Anthodon – a pareiasaur
  Antrodemus – possibly a synonym of Allosaurus
  Anzu
  Aoniraptor
  Aorun
  Apatodon – possibly a junior synonym of Allosaurus
  Apatoraptor
  Apatosaurus
  Appalachiosaurus
  Aquilarhinus
  Aquilops
  Aragosaurus
  Aralosaurus
  Aratasaurus
  "Araucanoraptor" – nomen nudum; Neuquenraptor
  Archaeoceratops
  Archaeodontosaurus
  Archaeopteryx
  Archaeoraptor – a chimaera of the bird Yanornis and the dromaeosaur Microraptor
  Archaeornis – junior synonym of Archaeopteryx
  Archaeornithoides
  Archaeornithomimus
  Arcovenator
  Arctosaurus - a non-dinosaurian reptile
  Arcusaurus
  Arenysaurus
  Argentinosaurus
  Argyrosaurus
  Aristosaurus – junior synonym of Massospondylus
  Aristosuchus
  Arizonasaurus – a rauisuchian
  Arkansaurus
  Arkharavia
  Arrhinoceratops
  Arstanosaurus
  Asfaltovenator
  Asiaceratops
  Asiamericana –  a fish
  Asiatosaurus
  Astrodon
  Astrodonius – junior synonym of Astrodon
  Astrodontaurus – junior synonym of Astrodon
  Astrophocaudia
  Asylosaurus
  Atacamatitan
  Atlantosaurus
  Atlasaurus
  Atlascopcosaurus
  Atrociraptor
  Atsinganosaurus
  Aublysodon
  Aucasaurus
  Augustia – preoccupied name, now known as Agustinia
  Augustynolophus
  Auroraceratops
  Aurornis
  Australodocus
  Australovenator
  Austrocheirus
  Austroposeidon
  Austroraptor
  Austrosaurus
  Avaceratops
  Avalonia – preoccupied name, now known as Avalonianus
  Avalonianus – a non-dinosaurian archosaur
  Aviatyrannis
  Avimimus
  Avipes – probably a non-dinosaurian dinosauromorph
  Avisaurus – an enantiornithine bird
  Azendohsaurus – a non-dinosaurian archosauromorph
caption: Replica of an Allosaurus skeleton.
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