Heyuannia ("from Heyuan") is a genus of oviraptorid dinosaur that lived during the Late Cretaceous Period in China. It was the first oviraptorid found in that country; most others were found in neighbouring Mongolia. Two species are known: H. huangi, named by Lü Junchang in 2002; and H. yanshini, originally named as a separate genus Ingenia by Rinchen Barsbold in 1981 (and renamed to Ajancingenia in 2013 due to the preoccupation of Ingenia).
|Skeletal reconstruction of H. huangi|
The type species, Heyuannia huangi, was named and described by Lü Junchang in 2002. The generic name refers to the city of Heyuan. The specific name honours Huang Dong, the director of the Heyuan Museum. The holotype, HYMV1-1, was discovered in Guangdong near Huangsha in layers of the Dalangshan Formation. It consists of a partial skeleton, including the skull. Six further skeletons were assigned as paratypes or referred to the species. Multiple other fossils have been found, including one which may retain possible reproductive organs. Thousands of eggs have also been uncovered at the site, some of them belonging to the genus and likely laid by Heyuannia.
H. yanshini was first described and named by Rinchen Barsbold in 1981, as a new genus and species Ingenia yanshini. The name "Ingenia" derives from the Ingen Khoboor Depression of Bayankhongor Province, Mongolia, from whence it was collected, while the specific name yanshini was chosen in honour of academician Aleksandr Leonidovich Yanshin (1911–1999), who was adviser and mentor to Rinchen Barsbold during his time at the Paleontological Institute in St. Petersburg, Russia.
The generic name Ingenia was preoccupied by the generic name of Ingenia mirabilis (Gerlach, 1957), a tripyloidid nematode. Thus, an alternative generic name, Ajancingenia, was proposed by Jesse Easter in 2013. The replacement generic name is derived also from ajanc (аянч; a traveler in Mongolian), as a Western allusion to sticking one's thumb out for hitchhiking, in reference to the first manual ungual of Ajancingenia which is twice as large as the second.
Heyuannia is a medium-sized oviraptorid. Gregory S. Paul in 2010 estimated its length at 1.5 metres, the weight at twenty kilograms. Its toothless skull is relatively short with a steep snout. It had very short arms and digits, and its first digit was reduced.
Heyuannia was assigned by Lü to the Oviraptoridae in 2002. Its exact placement within this group is uncertain. Later analyses either resulted in a position in the Oviraptorinae or the Ingeniinae. According to Lü the morphology of the shoulder girdle of Heyuannia supports the hypothesis that oviraptosaurians were secondarily flightless birds.
Preservation of the pigments biliverdin and protoporphyrin in eggshells belonging to Heyuannia indicate that they were blue-green in color. This coloration allowed for both camouflage and sexual signalling, also seen in American robins and ratites. The arrangement of the eggshells suggests a partially open nest arrangement for Heyuannia, and also indicates that it engaged in increased parental care.
The Barun Goyot Formation (West Goyot Formation) is a geological formation dating to the Late Cretaceous Period. It is located within and is widely represented in the Gobi Desert Basin, in the Ömnögovi Province of Mongolia.Caenagnathoidea
Caenagnathoidea ("recent jaw forms") is a group of advanced oviraptorosaurian dinosaurs from the Cretaceous Period of what are now Asia and North America. They are distinct for their characteristically short, beaked, parrot-like skulls, often with 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 (along with all maniraptoran dinosaurs) is close to the ancestry of birds. The most complete specimens have been found in Asia, representing members of the sub-group Oviraptorinae. Notable but fragmentary remains are also known from North America, almost all of which belong to the subgroup Elmisaurinae.The earliest definitive caenangnathoid is Microvenator celer, which dates to the late Aptian age of the early Cretaceous period, though the slightly earlier Caudipteryx from the lower Yixian Formation of China, may also be a member of this group.Citipati
Citipati (pronounced [ˈtʃiːt̪ɪpət̪i] in Hindi, meaning 'funeral pyre lord') is a genus of oviraptorid theropod dinosaur from the Late Cretaceous Period of what is now Mongolia (specifically, the Djadokhta Formation of Ukhaa Tolgod, in the Gobi Desert). It is one of the best-known oviraptorids, thanks to a number of well-preserved skeletons, including several specimens found in brooding positions atop nests of eggs. These nesting specimens have helped to solidify the link between non-avian dinosaurs and birds.
The type species, Citipati osmolskae, was described in 2001. A second, as yet unnamed species may also exist. Citipati is often confused with the similar Oviraptor.Conchoraptor
Conchoraptor (meaning "conch plunderer") is a genus of oviraptorid dinosaur from the late Cretaceous Period of what is now Asia.Corythoraptor
Corythoraptor (meaning "crested raptor") is a genus of crested oviraptorid theropod dinosaur from the Nanxiong Formation of China. It is known from one species, C. jacobsi, named after palaeontologist Louis L. Jacobs. Including it, there are seven oviraptorids known from the Nanxiong Formation, showing a high level of diversity in the area, and that the different taxa may have occupied different ecological niches.Dalangshan Formation
The Dalangshan Formation (simplified Chinese: 大塱山组; traditional Chinese: 大塱山組; pinyin: Dàlǎngshān Zǔ) is a geological formation in the Sanshui District of Guangdong Province, China, the strata of which date back to the Late Cretaceous period.
Dinosaur remains are among the fossils that have been recovered from the formation.Huanansaurus
Huanansaurus is an extinct genus of oviraptorid dinosaur that lived approximately 72 million years ago, between the Campanian and Maastrichtian, during the latter part of the Cretaceous period in what is now China, in the Nanxiong Formation.Jiangxisaurus
Jiangxisaurus is an extinct genus of oviraptorid theropod dinosaur from Late Cretaceous of China.
It was similar to Heyuannia, but with more strongly curved anterior claws and a thinner, frailer mandible.
This find is paleontologically significant because it contributes to current knowledge about the paleogeographical distribution of oviraptorids in southern China.Khaan
Khaan (; Mongol [χaːŋ] 'lord') was an oviraptorid dinosaur that was found in the Djadochta Formation of Mongolia and lived in the Late Cretaceous Period (Campanian), 75 million years ago.List of dinosaur genera
This list of dinosaurs is a comprehensive listing of all genera that have ever been included in the superorder Dinosauria, excluding class Aves (birds, both living and those known only from fossils) and purely vernacular terms.
The list includes all commonly accepted genera, but also genera that are now considered invalid, doubtful (nomen dubium), or were not formally published (nomen nudum), as well as junior synonyms of more established names, and genera that are no longer considered dinosaurs. Many listed names have been reclassified as everything from birds to crocodilians to petrified wood. The list contains 1559 names, of which approximately 1192 are considered either valid dinosaur genera or nomina dubia.Lü Junchang
Lü Junchang (Chinese: 吕君昌; 1965 – 9 October 2018) was a Chinese palaeontologist and professor at the Institute of Geology, Chinese Academy of Geological Sciences. An expert on Mesozoic reptiles, he described and named many dinosaur and pterosaur taxa including Tongtianlong, Qianzhousaurus, Heyuannia, Gannansaurus, Yunnanosaurus youngi, and Darwinopterus.Machairasaurus
Machairasaurus is a genus of oviraptorid dinosaur which was found in the Bayan Mandahu Formation, China dating to the late Cretaceous period.During the Sino-Canadian expeditions of 1988 and 1990 some skeletons of unknown oviraptorosaurians were discovered by Philip J. Currie in Inner Mongolia. Based on two of these a new genus was named and described by Nicholas R. Longrich, Currie and Dong Zhiming in 2010 with as type species Machairasaurus leptonychus. The generic name is derived from Greek μάχαιρα (makhaira), "short scimitar". The specific name is derived from Greek λεπτός (leptos), "slender", and ὄνυξ (onyx), "claw". The species name as a whole refers to the sabre-like claws of the hand.The holotype, IVPP V15979, was found in layers of the Bayan Mandahu dating from the late Campanian. It mainly consists of a left frontlimb, including the lower end of the lower arm, two carpal bones and a complete hand. Also some fragmentary foot elements were present. The other find is the paratype, IVPP V15980, consisting of a very fragmentary skeleton including tail vertebrae, chevrons, ribs, phalanges of the hands, fragments of the second and fourth metatarsals and pedal phalanges.Five oviraptorid specimens associated with a nest, the female having been found brooding near the eggs, may belong to Machairasaurus.Machairasaurus was a small bipedal theropod. The describers established a single autapomorphy, unique derived trait: the hand claws are very elongated and blade-like in side view, with a length four times that of the joint height. The long claws would be proof that basal oviraptorids used their hands to pull down branches; the more curved claws of more derived forms would have served to dig up roots.Machairasaurus was in 2010 assigned to the Oviraptoridae, more precisely to the Ingeniinae. It formed a smaller clade with "Ingenia" yanshini, Heyuannia huangi, Conchoraptor gracilis, and Nemegtomaia barsboldi.Macroolithus
Macroolithus is an oogenus (fossil-egg genus) of dinosaur egg belonging to the oofamily Elongatoolithidae. The type oospecies, M. rugustus, was originally described under the now-defunct oogenus name Oolithes. Three other oospecies are known: M. yaotunensis, M. mutabilis, and M. lashuyuanensis. They are relatively large, elongated eggs with a two-layered eggshell. Their nests consist of large, concentric rings of paired eggs. There is evidence of blue-green pigmentation in its shell, which may have helped camouflage the nests.
Macroolithus eggs have been found containing oviraptorid dinosaur embryos resembling Heyuannia. Multiple other associations between oviraptorid and elongatoolithids (including other eggs containing embryos, parents brooding on nests, and a pair of shelled Macroolithus-like eggs preserved within an oviraptorid's pelvis) confirm that the parent of Macroolithus was an oviraptorid.
It is found in Upper Cretaceous formations of central and eastern Asia; fossils have been found in Mongolia, Kazakhstan and China. In the Nanxiong formation in Southern China, Macroolithus fossils range up to and possibly over the Cretaceous-Tertiary boundary, which is traditionally assumed to mark the extinction of the non-avian dinosaurs. Some paleontologists have interpreted the record of dinosaur eggs at this formation as supporting a gradual extinction event, rather than a sudden cataclysmic event. However, other paleontologists believe that these interpretations are merely based on artifacts of erosion and redeposition in the early Paleogene.Nankangia
Nankangia is an extinct genus of caenagnathoid oviraptorosaurian dinosaur known from the Late Cretaceous Nanxiong Formation of Nankang County, Ganzhou City of Jiangxi Province, southeastern China. It contains a single species, Nankangia jiangxiensis. N. jiangxiensis coexisted with at least four other caenagnathoids, including an unnamed oviraptorid, Banji long, Ganzhousaurus nankangensis and Jiangxisaurus ganzhouensis. The relatively short dentary and non-downturned mandibular symphysis of Nankangia suggest that it may have been more herbivorous than carnivorous.Oviraptor
Oviraptor is a genus of small Mongolian theropod dinosaurs, first discovered by technician George Olsen in an expedition led by Roy Chapman Andrews, and first described by Henry Fairfield Osborn, in 1924. Its name is Latin for 'egg taker' or "egg seizer", referring to the fact that the first fossil specimen was discovered atop a pile of what were thought to be Protoceratops eggs, and the specific name philoceratops means "lover of ceratopsians", also given as a result of this find. In his 1924 paper, Osborn explained that the name was given due to the close proximity of the skull of Oviraptor to the nest (it was separated from the eggs by only 4 inches or 10 centimetres of sand). However, Osborn also suggested that the name Oviraptor "may entirely mislead us as to its feeding habits and belie its character". In the 1990s, the discovery of nesting oviraptorids like Citipati proved that Osborn was correct in his caution regarding the name. These finds showed that the eggs in question probably belonged to Oviraptor itself, and that the specimen was actually brooding its eggs, when it died at the nest.
Oviraptor lived in the late Cretaceous period, during the late Campanian stage about 75 million years ago; only one definitive specimen is known (with associated eggs), from the Djadokhta Formation of Mongolia, though a possible second specimen (also with eggs) comes from the northeast region of Inner Mongolia, China, in an area called Bayan Mandahu.Oviraptoridae
Oviraptoridae is a group of bird-like, herbivorous and omnivorous maniraptoran dinosaurs. Oviraptorids are characterized by their toothless, parrot-like beaks and, in some cases, elaborate crests. They were generally small, measuring between one and two metres long in most cases, though some possible oviraptorids were enormous. Oviraptorids are currently known only from the Late Cretaceous of Asia, with the most well-known species and complete specimens found only in the Gobi Desert of Mongolia and northwestern China.Shixinggia
Shixinggia is a genus of oviraptorosaurian dinosaur from the Late Cretaceous period of Shixing County, Guangdong, China. While no skull was recovered, the specimen (BVP-112) is known from a fair amount of post-cranial material that shows it was a fairly derived oviraptorosaur (slightly more advanced than Nomingia), of superfamily Caenagnathoidea. Lü et al. (2003, 2005) describe it as an oviraptorid, but it could possibly be a caenagnathid . Along with the more advanced Heyuannia, Shixinggia is one of the few oviraptorosaurs known from China.Tongtianlong
Tongtianlong (meaning "Tongtianyan dragon") is a genus of oviraptorid theropod dinosaurs that lived in the late Maastrichtian epoch of the late Cretaceous period. It contains one species, T. limosus.Wulatelong
Wulatelong is an extinct genus of basal oviraptorid dinosaur known from the Late Cretaceous Wulansuhai Formation (Campanian stage) of Bayan Mandahu, Linhe District of Inner Mongolia, northern China. It contains a single species, Wulatelong gobiensis.