List of stem bird taxa which became extinct during the K-Pg extinction event (i.e. present at or very near K-Pg boundary and not yet known above it).

• Pterosauromorphans (~6 species)
  • Pterosauria
    • Macronychoptera
      • Novialoidea
        • Breviquartossa
          • Monofenestrata
            • Pterodactyliformes
              • Caelidracones
                • Pterodactyloidea
                  • Eupterodactyloidea
                    • Ornithocheiroidea
                      • Pteranodontia
                        • Nyctosauridae
                          • Nyctosauridae sp. (North America)
                      • Azhdarchoidea
                        • Neoazhdarchia
                          • Azhdarchidae
                            • Arambourgiania philadelphiae (Arabia)
                            • Hatzegopteryx thambema (Eurasia)
                            • Phosphatodraco mauritanicus (Africa)
                            • Quetzalcoatlus
                              • Quetzalcoatlus northropi (North America)
                              • Quetzalcoatlus sp. (North America)

• Ornithischians (~15 species)
  • Genasauria
    • Thyreophora
      • Thyreophoroidea
        • Eurypoda
          • Ankylosauria
            • Ankylosauridae
              • Ankylosaurinae
                • Ankylosaurus magniventris (North America)
            • Nodosauridae
              • Nodosaurinae
                • Denversaurus schlessmani (North America)
    • Neornithischia
      • Cerapoda
        • Marginocephalia
          • Ceratopsia
            • Neoceratopsia
              • Coronosauria
                • Leptoceratopsidae
                  • Leptoceratops gracilis (North America)
                • Ceratopsoidea
                  • Ceratopsidae
                    • Chasmosaurinae
                      • Triceratopsini
                        • Torosaurus latus (North America)
                        • Triceratops
                          • Triceratops prorsus (North America)
        • Ornithopoda
          • Thescelosauridae
            • Thescelosaurinae
              • Thescelosaurus
                • Thescelosaurus garbani (North America)
                • Thescelosaurus neglectus (North America)
          • Iguanodontia
            • Dryomorpha
              • Ankylopollexia
                • Styracosterna
                  • Hadrosauriformes
                    • Hadrosauroidea
                      • Hadrosauridae
                        • Euhadrosauria
                          • Lambeosaurinae
                            • Aralosaurini
                              • Canardia garonnensis
                            • Lambeosaurini
                              • Amurosaurus riabinini
                              • Arenysaurus ardevoli
                              • Olorotitan arharensi
                            • Parasaurolophini
                              • Charonosaurus jiayinensis
                          • Saurolophinae
                            • Brachylophosaurini
                              • Wulagasaurus dongi
                            • Edmontosaurini
                              • Kerberosaurus manakini
                              • Edmontosaurus
                                • Edmontosaurus annectens (North America)

• Sauropodomorphans (~18 species)
  • Plateosauria
    • Massopoda
      • Anchisauria
        • Sauropoda
          • Gravisauria
            • Eusauropoda
              • Neosauropoda
                • Qinlingosaurus luonanensis
                • Macronaria
                  • Camarasauromorpha
                    • Titanosauriformes
                      • Somphospondyli
                        • Arkharavia heterocoelica
                        • Titanosauria
                          • Adamantisaurus mezzalirai
                          • Hypselosaurus priscus
                          • Paludititan nalatzensis
                          • Titanosaurus indicus
                          • Uberabatitan ribeiroi
                          • Balochisauridae
                            • Balochisaurus malkani
                            • Marisaurus jeffi
                          • Pakisauridae
                            • Khetranisaurus barkhani
                            • Pakisaurus balochistani
                            • Sulaimanisaurus gingerichi
                          • Titanosauroidea
                            • Lithostrotia
                              • Antarctosauridae
                                • Isisaurus colberti
                              • Nemegtosauridae
                                • Ampelosaurus atacis
                                • Rapetosaurus krausei
                              • Saltasauridae
                                • Opisthocoelicaudiinae
                                  • Alamosaurus sanjuanensis (North America)
                                • Saltasaurinae
                                  • Jainosaurus septentrionalis
                            • Lognkosauria
                              • Puertasaurus reuili

• Ceratosaurians (~19 species)
  • Neoceratosauria
    • Austrocheirus isasii (South America)
    • Betasuchus bredai (Eurasia)
    • Jubbulpuria tenuis (India)
    • Abelisauroidea
      • Noasauridae
        • Compsosuchus solus (India)
        • Laevisuchus indicus (India)
        • Masiakasaurus knopfleri (India)
        • Noasaurus leali (South America)
      • Abelisauria
        • Abelisauridae
          • Coeluroides largus (India)
          • Dryptosauroides grandis (India)
          • Indosuchus raptorius (India)
          • Lametasaurus indicus (India)
          • Ornithomimoides barasimlensis (India)
          • Ornithomimoides mobilis (India)
          • Vitakridrinda sulaimani (Eurasia)
          • Carnotaurinae
            • Pycnonemosaurus nevesi (South America)
          • Majungasaurinae
            • Indosaurus matleyi (India)
            • Majungasaurus crenatissimus (India)
            • Rahiolisaurus gujaratensis (India)
            • Rajasaurus narmadensis (India)

• Tyrannosauroids (~2 species)
  • Dryptosaurus aquilunguis
  • Tyrannosauridae
    • Tyrannosaurinae
      • Tyrannosaurus rex

• Ornithomimosaurians (~2 species)
  • Ornithomimidae
    • Struthiomimus
      • Struthiomimus sedens
    • Ornithomimus
      • Ornithomimus velox

• • Richardoestesia sp.