Maniraptora is a clade of coelurosaurian dinosaurs which includes the birds and the non-avian dinosaurs that were more closely related to them than to Ornithomimus velox. It contains the major subgroups Avialae, Dromaeosauridae, Troodontidae, Oviraptorosauria, and Therizinosauria. Ornitholestes and the Alvarezsauroidea are also often included. Together with the next closest sister group, the Ornithomimosauria, Maniraptora comprises the more inclusive clade Maniraptoriformes. Maniraptorans first appear in the fossil record during the Jurassic Period, and survive today as living birds.
Scansoriopterygidae is an extinct family of climbing and gliding maniraptoran dinosaurs. Scansoriopterygids are known from five well-preserved fossils, representing four species, unearthed in the Tiaojishan Formation fossil beds of Liaoning and Hebei, China.
Kuru is a genus of dromaeosaurid theropod from the Late Cretaceous Barun Goyot Formation of Mongolia. The genus contains only a single species, the type species Kuru kulla, which is known from a fragmentary skeleton including a partial skull.
Jeholornis is a genus of avialan dinosaurs that lived between approximately 122 and 120 million years ago during the early Cretaceous Period in China. Fossil Jeholornis were first discovered in the Jiufotang Formation in Hebei Province, China and additional specimens have been found in the older Yixian Formation.
Jixiangornis is a genus of basal avialan dinosaurs from the Early Cretaceous. Like later avialans, it had no teeth, but it also had a long tail, unlike modern birds. Since teeth were still present in some more derived short-tailed avialans, Jixiangornis seems to have evolved its toothlessness independently of modern birds. The long forelimb indicates at least some aerial ability. Jixiangornis is currently known only from a single specimen, a complete but juvenile skeleton. The fossil was found in the Yixian Formation near Beipiao City, western Liaoning, China.
Velociraptorinae is a subfamily of the theropod group Dromaeosauridae. The earliest velociraptorines are probably Nuthetes from the United Kingdom, and possibly Deinonychus from North America. However, several indeterminate velociraptorines have also been discovered, dating to the Kimmeridgian stage, in the Late Jurassic Period. These fossils were discovered in the Langenberg quarry, Oker near Goslar, Germany.
Maniraptoriformes is a clade of dinosaurs with pennaceous feathers and wings that contains ornithomimosaurs and maniraptorans. This group was named by Thomas Holtz, who defined it as "the most recent common ancestor of Ornithomimus and birds, and all descendants of that common ancestor."
Avialae is a clade containing the only living dinosaurs, the birds. It is usually defined as all theropod dinosaurs more closely related to birds (Aves) than to deinonychosaurs, though alternative definitions are occasionally used.
Paraves are a widespread group of theropod dinosaurs that originated in the Middle Jurassic period. In addition to the extinct dromaeosaurids, troodontids, anchiornithids, and possibly the scansoriopterygids, the group also contains the avialans, which include diverse extinct taxa as well as the over 10,000 species of living birds. Basal members of Paraves are well known for the possession of an enlarged claw on the second digit of the foot, which was held off the ground when walking in some species. A number of differing scientific interpretations of the relationships between paravian taxa exist. New fossil discoveries and analyses make the classification of Paraves an active subject of research.
Ornithothoraces is a group of avialan dinosaurs that includes all enantiornithes and the euornithes, which includes modern birds and their closest ancestors. The name Ornithothoraces means "bird thoraxes". This refers to the modern, highly advanced anatomy of the thorax that gave the ornithothoracines superior flight capability compared with more primitive avialans. This anatomy includes a large, keeled breastbone, elongated coracoids and a modified glenoid joint in the shoulder, and a semi-rigid rib cage. In spite of this at least the sternum seems to have developed convergently rather than being a true homology.
Pygostylia is a group of avialans which includes the Confuciusornithidae and all of the more advanced species, the Ornithothoraces.
Avebrevicauda is a group of theropod dinosaurs which includes all avialan species with ten or fewer free vertebrae in the tail. The group was named in 2002 by Gregory S. Paul to distinguish short-tailed avialans from their ancestors, such as Archaeopteryx, which had long, reptilian tails.
Longipterygidae is a family of early enantiornithean avialans from the Early Cretaceous epoch of China. All known specimens come from the Jiufotang Formation and Yixian Formation, dating to the early Aptian age, 125-120 million years ago.
Xiaotingia is a genus of anchiornithid theropod dinosaur from Middle Jurassic or early Late Jurassic deposits of western Liaoning, China, containing a single species, Xiaotingia zhengi.
Euornithes is a natural group which includes the most recent common ancestor of all avialans closer to modern birds than to Sinornis.
Aurornis is an extinct genus of anchiornithid theropod dinosaurs from the Jurassic period of China. The genus Aurornis contains a single known species, Aurornis xui. Aurornis xui may be the most basal ("primitive") avialan dinosaur known to date, and it is one of the earliest avialans found to date. The fossil evidence for the animal pre-dates that of Archaeopteryx lithographica, often considered the earliest bird species, by about 10 million years.
Anchiornithidae is a family of small paravian dinosaurs. Anchiornithids have been classified at varying positions in the paravian tree, with some scientists classifying them as a distinct family, a basal subfamily of Troodontidae, members of Archaeopterygidae, or an assemblage of dinosaurs that are an evolutionary grade within Avialae or Paraves.
Kompsornis is an extinct genus of avialan dinosaurs that lived during the Early Cretaceous period of China. The type and only known species is Kompsornis longicaudus; the specific name means "long-tailed". It is known from only a single fossil specimen from the Jiufotang Formation. Kompsornis was closely related to the well-known Jeholornis, another long-tailed avialan from China, but differs from it in features of its skeleton, particularly the fusion and growth rate of its bones. Like other jeholornithiforms, Kompsornis was a long-tailed avialan with long wings and possessed little or no teeth, with none identified in the single specimen of Kompsornis.
Overoraptor is an extinct genus of paravian theropod of uncertain affinities from the Late Cretaceous Huincul Formation of Argentinian Patagonia. The genus contains a single species, O. chimentoi, known from several bones of the hands, feet, and hips alongside some vertebrae.
Neimengornis is an extinct genus of jeholornithiform avialan dinosaurs that lived in what is now China during the Early Cretaceous. It contains one species, N. rectusmim, which is known from a single specimen, holotype IMMNH-PV00122, discovered in the Jiufotang Formation of Liaoning.
