Caudipteryx is a genus of small oviraptorosaur dinosaurs that lived in Asia during the Early Cretaceous, around 124.6 million years ago. They were feathered and extremely birdlike in their overall appearance, to the point that some paleontologists suggested it was a bird. Two species have been described: C. zoui, in 1998, and C. dongi, in 2000.
Confuciusornis is a genus of basal crow-sized avialan from the Early Cretaceous Period of the Yixian and Jiufotang Formations of China, dating from 125 to 120 million years ago. Like modern birds, Confuciusornis had a toothless beak, but closer and later relatives of modern birds such as Hesperornis and Ichthyornis were toothed, indicating that the loss of teeth occurred convergently in Confuciusornis and living birds. It was thought to be the oldest known bird to have a beak, though this title now belongs to an earlier relative Eoconfuciusornis. It was named after the Chinese moral philosopher Confucius. Confuciusornis is one of the most abundant vertebrates found in the Yixian Formation, and several hundred complete specimens have been found.
The Enantiornithes, also known as enantiornithines or enantiornitheans in literature, are a group of extinct avialans, the most abundant and diverse group known from the Mesozoic era. Almost all retained teeth and clawed fingers on each wing, but otherwise looked much like modern birds externally. Over eighty species of Enantiornithes have been named, but some names represent only single bones, so it is likely that not all are valid. The Enantiornithes became extinct at the Cretaceous–Paleogene boundary, along with Hesperornithes and all other non-avian dinosaurs.
Hesperornis is a genus of cormorant-like Ornithuran that spanned throughout the Campanian age, and possibly even up to the early Maastrichtian age, of the Late Cretaceous period. One of the lesser-known discoveries of the paleontologist O. C. Marsh in the late 19th century Bone Wars, it was an early find in the history of avian paleontology. Locations for Hesperornis fossils include the Late Cretaceous marine limestones from Kansas and the marine shales from Canada. Nine species are recognised, eight of which have been recovered from rocks in North America and one from Russia.
Psittacosaurus is a genus of extinct ceratopsian dinosaur from the Early Cretaceous of what is now Asia, existing between 126 and 101 million years ago. It is notable for being the most species-rich non-avian dinosaur genus. Up to 12 species are known, from across China, Mongolia, Russia, and Thailand. The species of Psittacosaurus were obligate bipeds at adulthood, with a high skull and a robust beak. One individual was found preserved with long filaments on the tail, similar to those of Tianyulong. Psittacosaurus probably had complex behaviours, based on the proportions and relative size of the brain. It may have been active for short periods of time during the day and night, and had well-developed senses of smell and vision.
Yanornis is an extinct genus of fish-eating Early Cretaceous birds. Two species have been described, both from Liaoning province, China: Yanornis martini, based on several fossils found in the 120-million-year-old Jiufotang Formation at Chaoyang, and Yanornis guozhangi, from the 124-million-year-old Yixian Formation.
Gansus is a genus of aquatic birds that lived during the Aptian age of the Early Cretaceous (Aptian-Albian) period in what are now Gansu and Liaoning provinces, western China. The rock layers from which their fossils have been recovered are dated to 120 million years ago. It was first described in 1984 on the basis of an isolated left leg. It is the oldest-known member of the Ornithurae, the group which includes modern birds (Neornithes) and extinct related groups, such as Ichthyornis and Hesperornithes.
Longipteryx is a genus of prehistoric bird which lived during the Early Cretaceous. It contains a single species, Longipteryx chaoyangensis. Its remains have been recovered from the Jiufotang Formation at Chaoyang in Liaoning Province, China. Apart from the holotype IVPP V 12325 - a fine and nearly complete skeleton — another entire skeleton and some isolated bones are known to date.
Cathayornis is a genus of enantiornithean birds from the Jiufotang Formation of Liaoning, People's Republic of China. It is known definitively from only one species, Cathayornis yandica, one of the first Enantiornithes found in China. Several additional species were once incorrectly classified as Cathayornis, and have since been reclassified or regarded as nomina dubia.
Sinornis is a genus of enantiornithean birds from the Lower Cretaceous Jiufotang Formation of the People's Republic of China.
Eoenantiornis is a genus of enantiornithean birds which lived during the early Cretaceous period. It is known from a single fossil specimen found in the Yixian Formation in Liaoning province, China.
Longchengornis is a genus of enantiornithean birds which lived during the early Cretaceous Period, about 120 mya, and is known from a fossil found in the Jiufotang Formation in Liaoning province, People's Republic of China. It contains the single species L. sanyanensis, though some researchers believe this to be a synonym of the similar species Cathayornis yandica.
Yixianornis is a bird genus from the early Cretaceous period. Its remains have been found in the Jiufotang Formation at Chaoyang dated to the early Aptian age, around 120 million years ago. Only one species, Yixianornis grabaui, is known at present. The specific name, grabaui, is named after American paleontologist Amadeus William Grabau, who surveyed China in the early 20th century.
Archaeorhynchus is a genus of beaked avialan stem-birds from the early Cretaceous period. A fossil of its only known species, Archaeorhynchus spathula, was first reported in 2005 by Zhou & Zhang to have been found in Yixian Formation rocks at Yixian, Liaoning province, China, showing a well-preserved and essentially complete skeleton. Two more complete specimens were found in Lower Cretaceous deposits of Jianchang, Liaoning, northeastern China, preserving new anatomical information. These deposits are 120 million years old, whereas the original specimen was 125 million years old, meaning the age range for this species is 125-120Ma.
Liaoningornis is a genus of bird from Lower Cretaceous China. It was collected from the dinosaur-bearing beds of the Sihetun locality, of the Yixian Formation, Shangyuan, near the city of Beipiao in Liaoning province. The only known species is Liaoningornis longidigitris. It was described by Linhai Hou in 1996 and 1997.
Zhongjianornis is a genus of beaked, pigeon-sized birds from the early Cretaceous period of China. It is known from one fossil found at Jianchang, Liaoning Province, in rocks of the Jiufotang Formation, representing the type species Zhongjianornis yangi.
Hongshanornithidae is an extinct group of early ornithuromorph birds from the early Cretaceous period of China. It includes the genera Hongshanornis and Tianyuornis from the Yixian Formation of Inner Mongolia, Longicrusavis from the Yixian Formation of Liaoning Province, Parahongshanornis from the Jiufotang Formation of Liaoning Province, and Archaeornithura, the oldest known member, from the Huajiying Formation of Hebei Province.
Songlingornithidae is a family of basal euornithean dinosaurs from the Early Cretaceous of China. All known specimens come from the Jiufotang Formation and the Yixian Formation, dating to the early Barremian and Aptian ages, 125–120 million years ago.
Houornis is a genus of enantiornithean birds from the Jiufotang Formation of Liaoning, People's Republic of China. It is known from a single species, Houornis caudatus, which had been once been classified as a species of Cathayornis, and has also been regarded as a nomen dubium.
Chiappeavis is a genus of enantiornithean bird from Early Cretaceous of northeastern China. The only species is Chiappeavis magnapremaxillo. Chiappeavis is classified within the family Pengornithidae. It is known from a single, almost complete skeleton including feather impressions discovered in the Jiufotang Formation of the Jehol Group. Long feathers formed a fan-shaped tail that was probably employed in flight.
