Ningyuansaurus Temporal range: Early Cretaceous, | |
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Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Clade: | Dinosauria |
Clade: | Saurischia |
Clade: | Theropoda |
Clade: | Pennaraptora |
Genus: | † Ningyuansaurus Ji et al., 2012 |
Type species | |
†Ningyuansaurus wangi Ji et al., 2012 |
Ningyuansaurus is a pennaraptoran dinosaur genus. It contains the single species Ningyuansaurus wangi, known from a fossil specimen from the Early Cretaceous Yixian Formation (Aptian stage, 124.6 Ma ago) of Jianchang, western Liaoning Province, People's Republic of China. It was originally thought to be the basalmost species of oviraptorosaur, based on its long skull and a greater number of teeth in comparison to any other known oviraptorosaur. However, later research showed that it is a member of Halszkaraptorinae. The generic name Ningyuansaurus is derived from Ningyuan, an ancient name for Xingcheng City. The specific name honors Wang Qiuwu, the private owner of the specimen who donated it for scientific study. The specimen is now in the Confuciusornis Museum in Xingcheng. [1]
The only known fossil specimen of N. wangi is notable for having a large number of teeth compared to more advanced oviraptorosaurs, but the teeth in the back of the upper jaw (maxilla) are still reduced in number compared to most other non-avialan theropods. The reduced number of maxillary teeth in Ningyuansaurus is shared with the scansoriopterygids and other basal oviraptorosaurs such as Incisivosaurus . Though the skull is poorly preserved, the specimen preserved at least 14 teeth in the lower jaw (dentary) and 10 teeth in the upper jaw, four in the premaxilla and six in the maxilla. The teeth were closely packed together and lacked serrations. The eyes were relatively large. The skull was generally triangular in shape but longer than other basal oviraptorosaurs like Caudipteryx , with a straight lower jaw unlike most other oviraptorosaurs. [1]
The arms were short, with longer upper arms (humeri) than lower arms (ulna). The legs were long, and the upper leg (femur) was longer than the pelvic bones. The tail was relatively long and feather impressions were found near the tip. Additional feather impressions were identified along the neck. [1]
Ji et al., 2012 considered Ningyuansaurus a basal member of Oviraptorosauria. However, some traits, such as the low iliofemoral ratio, low ischiopubic ratio and enlarged pedal ungual II are more similar to paravians. While a 2016 study recovered it as an Oviraptorosaur, [2] the only non-Oviraptorosaur taxa are Archaeopteryx , Velociraptor and Herrerasaurus and the study does not recover a paravian Velociraptor. [3]
The 2019 description of Hesperornithoides , which contains many Oviraptorosaurs recovers Ningyuansaurus as the sister taxon of Mahakala within Halszkaraptorinae: [4]
Unenlagiidae |
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Numerous small oval-shaped structures were found in the body cavity of the type specimen, each 10 millimetres (0.39 in) or less in diameter. These may be the remains of seeds, indicating that N. wangi was at least partially a seed-eater. [1]
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.
Sinornithosaurus is a genus of feathered dromaeosaurid dinosaur from the early Cretaceous Period of the Yixian Formation in what is now China. It was the fifth non–avian feathered dinosaur genus discovered by 1999. The original specimen was collected from the Sihetun locality of western Liaoning. It was found in the Jianshangou beds of the Yixian Formation, dated to 124.5 million years ago. Additional specimens have been found in the younger Dawangzhangzi bed, dating to around 122 million years ago.
Oviraptorosaurs are a group of feathered maniraptoran dinosaurs from the Cretaceous Period of what are now Asia and North America. They are distinct for their characteristically short, beaked, parrot-like skulls, with or without bony crests atop the head. They ranged in size from Caudipteryx, which was the size of a turkey, to the 8-meter-long, 1.4-ton Gigantoraptor. The group is close to the ancestry of birds. Some researchers such as Maryanska et al (2002) and Osmólska et al. (2004) have proposed that they may represent primitive flightless birds. The most complete oviraptorosaur specimens have been found in Asia. The North American oviraptorosaur record is sparse.
Sinovenator is a genus of troodontid dinosaur from China. It is from the early Cretaceous Period.
Sinusonasus is a genus of dinosaurs from the Early Cretaceous Period, recovered from the Yixian Formation. It lived in what is now the Liaoning Province of China. Sinusonasus was a theropod, specifically a troodontid dinosaur.
Liaoningosaurus is an unusual genus of basal ankylosaurid dinosaur from the Liaoning Province, China that lived during the Early Cretaceous in what is now the Yixian and Jiufotang Formation. The type and only species, Liaoningosaurus paradoxus, is known from more than 20 specimens, with some representing juveniles. It was named in 2001 by Xu, Wang and You.
Jeholosaurus is a genus of neornithischian dinosaur from the Early Cretaceous Period. It is thought to have been a herbivorous small ornithopod.
Incisivosaurus is a genus of small, probably herbivorous theropod dinosaurs from the early Cretaceous Period of what is now the People's Republic of China. The first specimen to be described, IVPP V13326, is a skull that was collected from the lowermost levels of the Yixian Formation in the Sihetun area, near Beipiao City, in western Liaoning Province. The most significant, and highly unusual, characteristic of this dinosaur is its apparent adaptation to an herbivorous or omnivorous lifestyle. It was named for its prominent, rodent-like front teeth, which show wear patterns commonly found in plant-eating dinosaurs. The specific name gauthieri honors Dr. Jacques Gauthier, a pioneer of the phylogenetic method of classification.
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.
Yixianopterus is a pterodactyloid pterosaur genus from the Barremian-Aptian-age Lower Cretaceous Yixian Formation of Liaoning, China. It is known from a single specimen, holotype JZMP-V-12, housed at the Benxi Geological Museum. This specimen was modified before acquisition, with much of the skull being fabricated. The Jinggangshan bedding in which the specimen was found is basaltic with siliciclastic sediments. Many organisms associated with this layer of the Yixian Formation are aquatic, indicating a marine environment with much volcanic activity.
Similicaudipteryx, meaning "similar to Caudipteryx", is a genus of theropod dinosaur of the family Caudipteridae.
Xixiasaurus is a genus of troodontid dinosaur that lived during the Late Cretaceous Period in what is now China. The only known specimen was discovered in Xixia County, Henan Province, in central China, and became the holotype of the new genus and species Xixiasaurus henanensis in 2010. The names refer to the areas of discovery, and can be translated as "Henan Xixia lizard". The specimen consists of an almost complete skull, part of the lower jaw, and teeth, as well as a partial right forelimb.
Jianchangnathus is an extinct genus of basal pterosaur from the Middle Jurassic Tiaojishan Formation of northeastern China.
Jianchangosaurus is a genus of therizinosaurian dinosaur that lived approximately 126 million years ago during the early part of the Cretaceous Period from the Yixian Formation in what is now China. The nearly complete juvenile specimen was missing only the distal tail. Jianchangosaurus was a small, lightly built, bipedal, ground-dwelling herbivore, that could grow up to an estimated 2 m (6.6 ft) long and was 1 m (3.3 ft) high at the hips.
This timeline of oviraptorosaur research is a chronological listing of events in the history of paleontology focused on the oviraptorosaurs, a group of beaked, bird-like theropod dinosaurs. The early history of oviraptorosaur paleontology is characterized by taxonomic confusion due to the unusual characteristics of these dinosaurs. When initially described in 1924 Oviraptor itself was thought to be a member of the Ornithomimidae, popularly known as the "ostrich" dinosaurs, because both taxa share toothless beaks. Early caenagnathid oviraptorosaur discoveries like Caenagnathus itself were also incorrectly classified at the time, having been misidentified as birds.
Liaodactylus is a genus of filter-feeding ctenochasmatid pterosaur from the Jurassic of China. The genus contains one species, L. primus, described by Zhou et al. in 2017. As an adaptation to filter-feeding, Liaodactylus had approximately 150 long, comb-like teeth packed closely together. It is both the earliest known ctenochasmatid and the first filter-feeding pterosaur from the Jurassic Yanliao Biota. Later and more specialized ctenochasmatids differ from Liaodactylus in having longer snouts, smaller openings in the skull, and more teeth. Within the Ctenochasmatidae, Liaodactylus was most closely related to the European Ctenochasma.
Beibeilong is a genus of large caenagnathid dinosaurs that lived in China during the Late Cretaceous epoch, about 96 million to 88 million years ago. The genus contains a single species, Beibeilong sinensis. The species was named and described in 2017 through analysis of an embryonic skeleton and partial nest with large eggs that were discovered in the Gaogou Formation of China between 1992 and 1993.
Daliansaurus is a genus of small troodontid theropod dinosaur, measuring approximately 1 metre long, from the Early Cretaceous of China. It contains a single species, D. liaoningensis, named in 2017 by Shen and colleagues from a nearly complete skeleton preserved in three dimensions. Daliansaurus is unusual in possessing an enlarged claw on the fourth digit of the foot, in addition to the "sickle claw" found on the second digit of the feet of most paravians. It also has long metatarsal bones, and apparently possesses bird-like uncinate processes. In the Lujiatun Beds of the Yixian Formation, a volcanically-influenced region with a cold climate, Daliansaurus lived alongside its closest relatives - Sinovenator, Sinusonasus, and Mei, with which it forms the group Sinovenatorinae.
Liaoningvenator is a genus of troodontid theropod dinosaur from the Early Cretaceous of China. It contains a single species, L. curriei, named after paleontologist Phillip J. Currie in 2017 by Shen Cai-Zhi and colleagues from an articulated, nearly complete skeleton, one of the most complete troodontid specimens known. Shen and colleagues found indicative traits that placed Liaoningvenator within the Troodontidae. These traits included its numerous, small, and closely packed teeth, as well as the vertebrae towards the end of its tail having shallow grooves in place of neural spines on their top surfaces.