Nankangia

Last updated

Nankangia
Temporal range: Late Cretaceous, 72–66  Ma
Nankangia.png
Lower jaw
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Clade: Dinosauria
Clade: Saurischia
Clade: Theropoda
Superfamily: Caenagnathoidea
Genus: Nankangia
et al., 2013
Type species
Nankangia jiangxiensis
et al., 2013

Nankangia is an extinct genus of caenagnathoid oviraptorosaurian dinosaur known from the Upper 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 but not limited to Corythoraptor , Banji , Ganzhousaurus and Jiangxisaurus . The relatively short dentary and non-downturned mandibular symphysis of Nankangia suggest that it may have been more herbivorous than carnivorous. Its diet consisted of leaves and seeds. [1]

Contents

Discovery

Scapulocoracoids Scapulocoracoids of Nankangia.png
Scapulocoracoids

Nankangia was first described and named by Lü Junchang, Yi Laiping, Zhong Hui and Wei Xuefang in 2013 and the type species is Nankangia jiangxiensis. The generic name honors the Chinese administrative unit Nankang County in Jiangxi Province, and the specific name honors the province where the holotype site in Nankang City is located. [1]

Restoration Nankangia Restoration.jpg
Restoration

Nankangia is known solely from the holotype GMNH F10003, a partial lower jaw and partial postcranial skeleton from a single individual, housed at the Ganzhou Museum of Natural History, Ganzhou City of Jiangxi Province. Postcranial material includes five complete dorsal vertebrae, one and one-half sacral vertebrae, nine complete and two partial caudal vertebrae, both scapulocoracoids, an incomplete furcula, a nearly complete right humerus, the complete right and most of the left ilia, the complete right and most of the left pubic bones, the complete right and a partial left ischia, both femora, the right tibia, and some dorsal ribs. [1]

The holotype was found in 2010 at the town of Longling of Nankang, Ganzhou City, by a local farmer who donated it to the Ganzhou Museum of Natural History. It was collected from the Nanxiong Formation, dating probably to the Maastrichtian stage of the Late Cretaceous. [1]

Description

Vertebral column Nankangia jiangxiensis.png
Vertebral column

Nankangia is distinguished from all other oviraptorosaurians based on a combination of traits, some of which are autapomorphic (i.e. unique). On the ventral surface near the base of the transverse process of the dorsal vertebrae two infradiapophyseal fossae are present. The sacral vertebrae bear slit-like pneumatic fossae. The neural spines of the anterior caudal vertebrae are wider transversely than anteroposteriorly, forming a large posterior fossa with a rugose central area. These vertebrae possess a large fossa on the anterior surface of the base of the transverse process (infraprezygapophyseal fossa) and as well as an infradiapophyseal fossa on the ventral surface of the transverse process. [1]

The femur and tibia of Nankangia are approximately the same length. Its femoral neck extends dorsomedially at about 90° to the shaft. It has relatively small ratio of height to length of ilium (0.36), which is additionally shorter than the femur as seen in Yulong and Khaan . The ilium of Nankangia is uniquely shaped, and among oviraptorosaurians, resembles the ilia of Chirostenotes , Rinchenia , Heyuannia and Shixinggia , and clearly differs from the ilium of Luoyanggia . Due to the lack of well-preserved corresponding elements between the specimens of Nankangia and Wulatelong , from the Wulansuhai Formation of Inner Mongolia, Lü et al. (2013) could not differentiated between them. [1]

Pelvic girdle Pelvic girdle of Nankangia.png
Pelvic girdle

The rostral end of the mandibular symphyseal region is not downturned in Nankangia, as in caenagnathids, Incisivosaurus , Luoyanggia and Ganzhousaurus . Unlike the V-shaped mandibular symphysis of Luoyanggia, Nankangia and other oviraptorosaurs have a U-shaped mandibular symphysis. Although Nankangia and Jiangxisaurus possess similar lower jaws, the medial margin of the humerus is more curved medially in Nankangia than it is in Jiangxisaurus. Based on its phylogenetic position, Nankangia displays five other possible autapomorphies, including an anteriorly projecting acromion, separated anterior and greater trochanters, dorsoventral extension of the pubic peduncle that is deeper than the ischial peduncle, and the lack of a downturned symphyseal portion of the dentary. The latter trait is shared with the coeval Ganzhousaurus and Jiangxisaurus, suggesting a primarily herbivorous diet, whereas Banji and another unnamed oviraptorid from the same formation may have been more carnivorous, as they bear a downturned mandibular symphysis. [1]

Phylogeny

leg bones Nankangia leg bones.png
leg bones

The phylogenetic position of Nankangia was explored by Lü et al. (2013) using the data matrix published with the description of Yulong . The obtained topology was resolved, with the exception of a polytomy between the "Ingeniinae", Oviraptor , and the rest of the Oviraptorinae. Lü et al. (2013) suggested that Nankangia may form a clade with Gigantoraptor and Chirostenotes, and therefore refrained from including the former two taxa in the Oviraptoridae, even though this was not supported by their phylogenetic analysis. [1] However, Oviraptoridae is currently defined as a stem-based taxon that excludes caenagnathids but includes Oviraptor , [2] [3] and an alternative definition was not suggested by Lü et al. (2013). [1] The cladogram below shows the phylogenetic position of Nankangia following this analysis, as the sister taxon to the clade mislabeled as Oviraptoridae. [1]

Oviraptorosauria  

Incisivosaurus

Caudipteryx

Avimimus

Chirostenotes

Gigantoraptor

Nankangia

Oviraptoridae

Yulong

Oviraptor

Rinchenia

Citipati

Citipati sp.

"Ingeniinae"

Khaan

Conchoraptor

Machairasaurus

Ajancingenia

Heyuannia

Nemegtomaia

The phylogenetic analysis of Lü et al. (2017) recovered it as an oviraptorid closely related to Yulong and Nomingia [4] and the phylogenetic analysis of Wei et al. (2022) found it to be the most basal oviraptorid. [5]

See also

Related Research Articles

<span class="mw-page-title-main">Oviraptoridae</span> Extinct family of dinosaurs

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.

<span class="mw-page-title-main">Oviraptorosauria</span> Extinct clade of dinosaurs

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.

<i>Caenagnathus</i> Genus of dinosaur from the Late Cretaceous period

Caenagnathus is a genus of caenagnathid oviraptorosaurian dinosaur from the late Cretaceous period. It is known from partial remains including lower jaws, a tail vertebra, hand bones, and hind limbs, all found in the Dinosaur Park Formation of Alberta, Canada. Caenagnathus measured about 2.5 m (8.2 ft) long and weighed about 96–100 kg (212–220 lb).

<i>Nemegtomaia</i> Extinct genus of dinosaurs

Nemegtomaia is a genus of oviraptorid dinosaur from what is now Mongolia that lived in the Late Cretaceous Period, about 70 million years ago. The first specimen was found in 1996, and became the basis of the new genus and species N. barsboldi in 2004. The original genus name was Nemegtia, but this was changed to Nemegtomaia in 2005, as the former name was preoccupied. The first part of the generic name refers to the Nemegt Basin, where the animal was found, and the second part means "good mother", in reference to the fact that oviraptorids are known to have brooded their eggs. The specific name honours the palaeontologist Rinchen Barsbold. Two more specimens were found in 2007, one of which was found on top of a nest with eggs, but the dinosaur had received its genus name before it was found associated with eggs.

<i>Nanshiungosaurus</i> Extinct genus of reptiles

Nanshiungosaurus is a genus of therizinosaurid that lived in what is now Asia during the Late Cretaceous of South China. The type species, Nanshiungosaurus brevispinus, was first discovered in 1974 and described in 1979 by Dong Zhiming. It is represented by a single specimen preserving most of the cervical and dorsal vertebrae with the pelvis. A supposed and unlikely second species, "Nanshiungosaurus" bohlini, was found in 1992 and described in 1997. It is also represented by vertebrae but this species however, differs in geological age and lacks authentic characteristics compared to the type, making its affinity to the genus unsupported.

<i>Banji</i> Extinct genus of dinosaurs

Banji is an extinct genus of oviraptorid dinosaur that lived approximately 66 million years ago during the later part of the Cretaceous Period in what is now China. It was a small, lightly built, ground-dwelling, bipedal carnivore, that was an estimated 65 cm (2.1 ft) long, as a juvenile.

<i>Gigantoraptor</i> Extinct genus of dinosaurs

Gigantoraptor is a genus of large oviraptorosaur dinosaur that lived in Asia during the Late Cretaceous period. It is known from the Iren Dabasu Formation of Inner Mongolia, where the first remains were found in 2005.

<span class="mw-page-title-main">Caenagnathoidea</span> Extinct superfamily of reptiles

Caenagnathoidea 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 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 Nanxiong Formation is a Late Cretaceous geologic formation in Guangdong Province. Dinosaur remains are among the fossils that have been recovered from the formation.

<i>Macroolithus</i> Oogenus of dinosaur egg

Macroolithus is an oogenus 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.

<i>Yulong mini</i> Extinct species of dinosaur

Yulong is an extinct genus of derived oviraptorid theropod dinosaur known from the Late Cretaceous Qiupa Formation of Henan Province, central China. It contains a single species, Yulong mini. It is known from many juvenile specimens that represent some of the smallest known oviraptorids and also a single subadult specimen.

<i>Ganzhousaurus</i> Extinct genus of dinosaurs

Ganzhousaurus is an extinct genus of oviraptorid dinosaur known from the Late Cretaceous Nanxiong Formation of Nankang County, Ganzhou City of Jiangxi Province, southern China. It was found in a Maastrichtian deposit and contains a single species, Ganzhousaurus nankangensis. It is distinguished by a combination of primitive and derived features.

<i>Jiangxisaurus</i> Extinct genus of dinosaurs

Jiangxisaurus is an extinct genus of oviraptorid theropod dinosaur from the Late Cretaceous Nanxiong Formation of southern 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. It was most likely a herbivorous animal along with its close relatives Nankangia and Ganzhousaurus.

<i>Qianzhousaurus</i> Extinct genus of dinosaurs

Qianzhousaurus is a genus of tyrannosaurid dinosaur that lived in Asia during the Maastrichtian age of the Late Cretaceous period. There is currently only one species named, the type species Qianzhousaurus sinensis, which is a member of the tribe Alioramini and most closely related to Alioramus, the only other known alioramin.

<span class="mw-page-title-main">Timeline of oviraptorosaur research</span>

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.

<i>Huanansaurus</i> Extinct genus of dinosaurs

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.

<i>Tongtianlong</i> Extinct genus of dinosaurs

Tongtianlong 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.

<i>Beibeilong</i> Caenagnathid dinosaur genus from the Late Cretaceous

Beibeilong is a genus of large caenagnathid dinosaurs that lived in Asia 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.

<i>Corythoraptor</i> Extinct genus of dinosaurs

Corythoraptor is a genus of oviraptorid dinosaur from the late Maastrichtian Nanxiong Formation of South China. It contains one species, C. jacobsi, known from a single well-preserved skeleton, and named after paleontologist Louis L. Jacobs. It bears a tall crest similar to that of the modern cassowary, and possibly had a similar functionality of display and resonance to detect lower-frequency sounds.

<i>Gobiraptor</i> Extinct genus of dinosaurs

Gobiraptor is a genus of oviraptorid maniraptoran dinosaur from the Maastrichtian-age Nemegt Formation of Mongolia. The type and only species is Gobiraptor minutus, known from a single incomplete specimen—the holotype MPC-D 102/111. It has been found not to be closely related to the other oviraptorids it shared its environment with.

References

  1. 1 2 3 4 5 6 7 8 9 10 Lü, J.; Yi, L.; Zhong, H.; Wei, X. (2013). Dodson, Peter (ed.). "A New Oviraptorosaur (Dinosauria: Oviraptorosauria) from the Late Cretaceous of Southern China and Its Paleoecological Implications". PLOS ONE. 8 (11): e80557. Bibcode:2013PLoSO...880557L. doi: 10.1371/journal.pone.0080557 . PMC   3842309 . PMID   24312233.
  2. Mortimer, Michael: The Theropod Database: Oviraptoridae. Retrieved 2013-NOV-29.
  3. Lü, J.; Currie, P. J.; Xu, L.; Zhang, X.; Pu, H.; Jia, S. (2013). "Chicken-sized oviraptorid dinosaurs from central China and their ontogenetic implications". Naturwissenschaften. 100 (2): 165–175. Bibcode:2013NW....100..165L. doi:10.1007/s00114-012-1007-0. PMID   23314810. S2CID   206871470.
  4. Lü, J.; Li, G; Kundrát, M.; Lee, Y.; Zhenyuan, S.; Yoshitsugu, K.; Caizhi, S.; Fangfang, T.; Hanfeng, L (2017). "High diversity of the Ganzhou Oviraptorid Fauna increased by a new "cassowary-like" crested species". Scientific Reports. 7 (1): 6393. Bibcode:2017NatSR...7.6393L. doi:10.1038/s41598-017-05016-6. PMC   5532250 . PMID   28751667.
  5. Wei, Xuefang; Kundrát, Martin; Xu, Li; Ma, Waisum; Wu, Yan; Chang, Huali; Zhang, Jiming; Zhou, Xuanyu (2022). "A new subadult specimen of oviraptorid Yulong mini (Theropoda: Oviraptorosauria) from the Upper Cretaceous Qiupa Formation of Luanchuan, central China". Cretaceous Research. 138: 105261. Bibcode:2022CrRes.13805261W. doi:10.1016/j.cretres.2022.105261. ISSN   0195-6671. S2CID   248977151.