Parvicursor

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Parvicursor
Temporal range:
Late Cretaceous, 72  Ma
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Parvicursor.jpg
A reconstruction of Parvicursor sitting on a nest
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Clade: Dinosauria
Clade: Saurischia
Clade: Theropoda
Family: Alvarezsauridae
Subfamily: Parvicursorinae
Genus: Parvicursor
Karhu & Rautian, 1996
Species:
P. remotus
Binomial name
Parvicursor remotus
Karhu & Rautian, 1996
Synonyms

Parvicursor (meaning "small runner") is a genus of tiny maniraptoran dinosaur with long slender legs for fast running. [3]

Contents

Discovery and naming

The holotype PIN no. 4487/25, mostly consisting of vertebrae, the pelvis and the right hindlimb, was discovered in 1992 and described in 1996. [4] It was discovered in Barun Goyot Formation of Khulsan, Mongolia, dated at approximately 72 million years old. [1]

Description

At only about 39 centimetres (15 in; 1.28 ft) from snout to end of tail, and 162 g (5.7 oz) in weight, it was initially seen as one of the smallest non-avian dinosaurs known from an adult specimen. [5] However, in 2022 its holotype was concluded to represent a juvenile individual. [1]

Size of P. remotus (green) compared to other small alvarezsaurids Alvarezsaurid scale martyniuk.png
Size of P. remotus (green) compared to other small alvarezsaurids

Like other members of the family Alvarezsauridae, the forelimbs of Parvicursor were short and stubby, with hands all but completely reduced to a single large claw, possibly useful for opening tough termite mounds or other types of digging. It is unlikely that the claw could have served much for defense, as it was short and not adapted for flexible movements it is more likely it would do as the animal's name implies: cursor means runner.

Close relatives include Shuvuuia and Mononykus , and together with these it is classified in the alvarezsaurid subfamily Parvicursorinae.

Taxonomy

There may be a second, yet-unnamed, species of Parvicursor. Two specimens of tiny alvarezsaurids were described by Suzuki et al. in 2002. These authors considered the specimens to be juvenile Shuvuuia , which lived in the same formation. [6] However, a study by Nick Longrich and Phil Currie in 2009 suggested that several characters of the skeleton, including fused wrist and pelvic bones, indicated that these specimens were in fact adults of a tiny alvarezsaurid species. A phylogenetic analysis found that they grouped together with Parvicursor, and the authors provisionally referred them to Parvicursor sp. pending further study. [7]

It has been suggested that Linhenykus and Ceratonykus may be junior synonyms of Parvicursor. [2] [1]

Phylogeny

Parvicursor in a cladogram after Fowler et al. (2020): [8]

Alvarezsauroidea

Related Research Articles

<i>Shuvuuia</i> Extinct family of bird-like dinosaurs

Shuvuuia is a genus of bird-like theropod dinosaur from the late Cretaceous period of Mongolia. It is a member of the family Alvarezsauridae, small coelurosaurian dinosaurs which are characterized by short but powerful forelimbs specialized for digging. The type species is Shuvuuia deserti, or "desert bird". The name Shuvuuia is derived from the Mongolian word shuvuu (шувуу) meaning "bird".

<span class="mw-page-title-main">Alvarezsauridae</span> Family of extinct long-legged dinosaurs

Alvarezsauridae is a family of small, long-legged dinosaurs. Although originally thought to represent the earliest known flightless birds, they are now thought to be an early diverging branch of maniraptoran theropods. Alvarezsaurids were highly specialized. They had tiny but stout forelimbs, with compact, bird-like hands. Their skeletons suggest that they had massive breast and arm muscles, possibly adapted for digging or tearing. They had long, tube-shaped snouts filled with tiny teeth. They have been interpreted as myrmecophagous, adapted to prey on colonial insects such as termites, with the short arms acting as effective digging instruments to break into nests.

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

Dromiceiomimus is a genus of ornithomimid theropod from the Late Cretaceous of Alberta, Canada. The type species, D. brevitertius, is considered a synonym of Ornithomimus edmontonicus by some authors, while others consider it a distinct and valid taxon. It was a small ornithomimid that weighed about 135 kilograms (298 lb).

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

Avimimus, meaning "bird mimic", is a genus of oviraptorosaurian theropod dinosaur, named for its bird-like characteristics, that lived in the late Cretaceous in what is now Mongolia, around 85 to 70 million years ago.

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

Mononykus is a genus of alvarezsaurid dinosaur that lived during the Late Cretaceous in what is now Asia on the Nemegt Formation, about 70 million years ago.

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

Patagonykus is a genus of theropod dinosaur from the Upper Cretaceous of Argentina. This alvarezsauroid was discovered in exposures of the Portezuelo Formation (Turonian-Coniacian) of the Rio Neuquén Subgroup in the Neuquén Basin, Neuquen Province of Patagonia, Argentina. The holotype consists of an incomplete but well-preserved skeleton, lacking a skull, but including many vertebrae, the coracoids, a partial forelimb, pelvic girdle, and hindlimbs. Patagonykus has been classed with the Alvarezsauridae, a family which includes such taxa as the Mongolian Mononykus and the Argentinian Alvarezsaurus. In 2010 Gregory S. Paul estimated its length at 1 meter and its weight at 3.5 kg.

<span class="mw-page-title-main">Barun Goyot Formation</span> Geological formation in Mongolia

The Barun 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.

<span class="mw-page-title-main">Djadochta Formation</span> Geologic formation in Mongolia

The Djadochta Formation is a highly fossiliferous geological formation situated in Central Asia, Gobi Desert, dating from the Late Cretaceous period, about 75 million to 71 million years ago. The type locality is the Bayn Dzak locality, famously known as the Flaming Cliffs. Reptile and mammal remains are among the fossils recovered from the formation.

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

Albertonykus is an alvarezsaurid dinosaur from the Maastrichtian-age rocks of the Horseshoe Canyon Formation of Alberta, Canada. It is known from forelimb and hindlimb remains from multiple individuals. All but two of the specimens come from a bonebed dominated by Albertosaurus, located at the top of Unit 4 of the Horseshoe Canyon Formation, dating to ~68.5 million years ago.

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

Ceratonykus is a monospecific genus of alvarezsaurid dinosaur from Mongolia that lived during the Late Cretaceous in what is now the Barun Goyot Formation. The type and only species, Ceratonykus oculatus, is known from a fragmentary skeleton, including an incomplete skull, of an adult individual. It was named and described in 2009 by Vladimir Alifanov and Rinchen Barsbold. Its describers questioned the traditional placement of alvarezsaurs in Theropoda, instead suggesting they were ornithischians, but this has not been accepted since. Ceratonykus has an estimated length of 75 centimetres and weight of 760 grams. It has been considered as a possible junior synonym of Parvicursor.

<i>Kol ghuva</i> Extinct species of dinosaur

Kol is an extinct genus of coelurosaurian theropod dinosaur from the Late Cretaceous of Mongolia. The type and only species is Kol ghuva. The type specimen was excavated from the Ukhaa Tolgod locality of the Djadochta Formation, dating to about 75 million years ago. It is believed to have been about twice the size of the contemporaneous Shuvuuia. However, unlike Shuvuuia, which is known from many well preserved specimens, and although Ukhaa Tolgod has been thoroughly explored, Kol is known only from one complete foot, suggesting that it must have been relatively rare in that ecosystem.

<span class="mw-page-title-main">Alvarezsauroidea</span> Extinct superfamily of dinosaurs

Alvarezsauroidea is a group of small maniraptoran dinosaurs. Alvarezsauroidea, Alvarezsauridae, and Alvarezsauria are named for the historian Gregorio Álvarez, not the more familiar physicist Luis Alvarez, or his son geologist Walter Alvarez who jointly proposed that the Cretaceous–Paleogene extinction event was caused by an impact event. The group was first formally proposed by Choiniere and colleagues in 2010, to contain the family Alvarezsauridae and non-alvarezsaurid alvarezsauroids, such as Haplocheirus, which is the basalmost of the Alvarezsauroidea. The discovery of Haplocheirus extended the stratigraphic evidence for the group Alvarezsauroidea about 63 million years further in the past. The division of Alvarezsauroidea into the Alvarezsauridae and the non-alvarezsaurid alvarezsauroids is based on differences in their morphology, especially in their hand morphology.

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

Linhenykus is an extinct genus of alvarezsaurid theropod dinosaur from the Late Cretaceous of Inner Mongolia, China. It is the most basal known member of the Parvicursorinae. The genus gets its name from Linhe, a city near the site where the fossil was first found and Greek nykus, "claw". The specific name is derived from Greek monos, "single", and daktylos, "finger", a reference to the fact that it is the only known non-avian dinosaur to have had but a single digit.

<i>Bonapartenykus</i> A large alvarezsauroid dinosaur

Bonapartenykus is a monospecific genus of alvarezsauroid dinosaur from Argentina that lived during the Late Cretaceous (Campanian-Maastrichtian) in what is now the upper Allen Formation of the Río Negro Province. The type and only species, Bonapartenykus ultimus, is known from a nearly articulated but partial skeleton that was found in close association to two incomplete eggs and several clusters of eggshells belonging to the oogenus Arriagadoolithus. Bonapartenykus was named in 2012 by Federico L. Agnolin, Jaime E. Powell, Fernando E. Novas and Martin Kundrát. Bonapartenykus has an estimated length of 2.5 m (8.2 ft) and weight of 72 kg (159 lb), making it the largest member of the clade Alvarezsauroidea.

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

Trierarchuncus is a monotypic genus of alvarezsaurid theropod which includes a single species, Trierarchuncus prairiensis, which is known from fossils found in deposits of the Hell Creek Formation in Montana. It is the youngest known alvarezsaurid and one of the last non-avian dinosaurs, going extinct during the Cretaceous–Paleogene extinction event, which occurred approximately 66 million years ago.

Khulsanurus is an extinct genus of alvarezsaurid theropod dinosaur from the Late Cretaceous Barungoyot Formation of the Khulsan Locality in the Gobi Desert region of Mongolia. The type and only species is Khulsanurus magnificus.

<i>Ondogurvel</i> Genus of alvarezsaurid dinosaur

Ondogurvel is a genus of alvarezsaurid dinosaur from the Late Cretaceous (Campanian) Barun Goyot Formation in southern Mongolia. The type and only species is O. alifanovi, known from a partial skeleton consisting of fragments of two last dorsal vertebrae, three anterior sacral vertebrae, right ilium, left and right pubis and ischium, articulated right tibia, fibula, metatarsals II and IV, and phalanges IV-1 and IV-2, right carpometacarpus, left and right manual phalanx II-1, right femur, left pedal phalanx II-1, and fragments of unidentified phalanges.

<i>Natovenator</i> Genus of dromaeosaurid dinosaurs from the Late Cretaceous

Natovenator is a genus of halszkaraptorine dromaeosaurid dinosaur from the Late Cretaceous Barun Goyot Formation of Mongolia. The genus is known from a single species, N. polydontus. Natovenator is crucial to the understanding of halszkaraptorines due to it providing more support for the semi-aquatic lifestyle that has been proposed for this clade. This discovery is important as the semi-aquatic lifestyles of halszkaraptorines was contested in early 2022.

<i>Jaculinykus</i> Genus of alvarezsaurid dinosaurs

Jaculinykus is an extinct genus of alvarezsaurid theropod dinosaur from the Late Cretaceous Baruungoyot Formation of Mongolia. The genus contains a single species, J. yaruui, known from a nearly complete articulated skeleton including bones of the skull. Jaculinykus is notable for its unique hand, which has a hypertrophied first digit and greatly reduced second digit, which is intermediate between the tridactyl hand of Shuvuuia and monodactyl hand of Linhenykus.

References

  1. 1 2 3 4 Averianov AO, Lopatin AV (2022). "A re-appraisal of Parvicursor remotus from the Late Cretaceous of Mongolia: implications for the phylogeny and taxonomy of alvarezsaurid theropod dinosaurs". Journal of Systematic Palaeontology. 19 (16): 1097–1128. doi:10.1080/14772019.2021.2013965. S2CID   247222017.
  2. 1 2 Dyke, G. J.; Naish, D. (2011). "What about European alvarezsauroids?". Proceedings of the National Academy of Sciences. 108 (22): E147. Bibcode:2011PNAS..108E.147D. doi: 10.1073/pnas.1101602108 . PMC   3107280 . PMID   21540333.
  3. Parvicursor from Palaeos (technical)
  4. Karhu, A.A. and Rautian, A.S. (1996). "A new family of Maniraptora (Dinosauria: Saurischia) from the Late Cretaceous of Mongolia". Paleontological JournalRussian Academy of Sciences 30(5): 583-592.
  5. Which was the smallest dinosaur? Archived 2011-07-06 at the Wayback Machine Royal Tyrrell Museum. Last accessed 2008-05-23.
  6. Suzuki, S.; Chiappe, L.M.; Dyke, G.J.; Watabe, M.; Barsbold, R.; Tsogtbaatar, K. (2002). "A new specimen of Shuvuuia deserti Chiappe, et al. 1998 from the Mongolian Late Cretaceous with a discussion of the relationships of alvarezsaurids to other theropod dinosaurs". Contributions in Science, Natural History Museum of Los Angeles County. 494: 1–18.
  7. Longrich, Nicholas R.; Currie, Philip J. (2009). "Albertonykus borealis, a new alvarezsaur (Dinosauria: Theropoda) from the Early Maastrichtian of Alberta, Canada: Implications for the systematics and ecology of the Alvarezsauridae". Cretaceous Research. 30 (1): 239–252. doi:10.1016/j.cretres.2008.07.005.
  8. Denver W. Fowler; John P. Wilson; Elizabeth A. Freedman Fowler; Christopher R. Noto; Daniel Anduza; John R. Horner (2020). "Trierarchuncus prairiensis gen. et sp. nov., the last alvarezsaurid: Hell Creek Formation (uppermost Maastrichtian), Montana". Cretaceous Research. 116: Article 104560. doi: 10.1016/j.cretres.2020.104560 . S2CID   225630913.