Gobisaurus Temporal range: Early Cretaceous, | |
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Speculative life restoration | |
Scientific classification ![]() | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Clade: | Dinosauria |
Clade: | † Ornithischia |
Clade: | † Thyreophora |
Clade: | † Ankylosauria |
Family: | † Ankylosauridae |
Genus: | † Gobisaurus Vickaryous et al., 2001 |
Species: | †G. domoculus |
Binomial name | |
†Gobisaurus domoculus Vickaryous et al., 2001 | |
Synonyms | |
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Gobisaurus is an extinct genus of herbivorous basal ankylosaurid ankylosaur from the Lower Cretaceous of China ( Nei Mongol Zizhiqu). The genus is monotypic, containing only the species Gobisaurus domoculus. [2]
The Sino-Soviet Expeditions (1959–1960) discovered an ankylosaurian skeleton in the Gobi Desert of Inner Mongolia near Moartu, in the region of the Alashan Desert. The find was largely neglected until fossils were selected for a travelling exhibition touring the globe between 1990 and 1997, in the context of the China-Canada Dinosaur Project. The postcranial skeleton could not be located but the skull was displayed, informally labelled "Gobisaurus", at the time a nomen nudum .
In 2001, Matthew K. Vickaryous, Anthony P. Russell, Philip John Currie and Zhao Xijin named and described the type species Gobisaurus domoculus. The generic name means "Gobi (Desert) lizard," referring to its provenance. The specific name means "hidden from view" in Latin, referring to its being overlooked for three decades. [3]
The holotype, IVPP V12563, was found in a layer of the Miaogou Formation (Maortu locality; originally interpreted as the nearby Ulansuhai Formation). [1] In 2001, an Aptian age was presumed but later studies indicate it dated from the younger Turonian. It consists of a skull and the as yet undescribed postcranial remains. [3]
In 2014, Victoria Arbour concluded that Zhongyuansaurus , the type specimen of which, HGM 41HIII-0002, includes extensive postcranial remains, was a possible junior synonym of Gobisaurus. [4]
Gobisaurus is a large ankylosaurian. The skull measured 46 centimetres (18 in) in length and 45 centimetres (18 in) across. [2]
Gobisaurus domoculus shares many cranial similarities with Shamosaurus scutatus, including a rounded squamosal, short squamosal horns, low supraorbital bosses, large elliptical orbital fenestrae and external nares (oval eye sockets and nostrils), the cross-section of the eye sockets being about a fifth of skull length, a deltoid dorsal profile with a narrow rostrum (a narrow, kite-shaped, snout in top view), quadratojugal protuberances (cheek horns), and caudolaterally directed paroccipital processes (extensions of the rear skull pointing to behind and sideways). But the two taxa may be distinguished by differences in the length of the maxillary tooth row (26,6% instead of 40% of total skull length with Gobisaurus), an unfused basipterygoid-pterygoid process in Gobisaurus, the front of the pterygoid being in e vertical position, the presence on an elongate vomerine premaxillary process in Gobisaurus, and the presence of cranial sculpting in Shamosaurus, but not in Gobisaurus. [3] [2] This latter difference was denied by Arbour who concluded that the degree of sculpting was roughly the same. [4]
The external nostrils had about 23% of skull length. [3]
The HGM 41HIII-0002 specimen preserves a tail club "handle": the vertebrae toward the end of the tail interlock tightly, making the end stiff. However, this specimen does not appear to have a tail club "knob", the bulbous osteoderms seen in derived ankylosaurids. [5]
Gobisaurus was placed in the Ankylosauridae in 2001. [3] Vickaryous et al., 2004 found that a clade formed by Shamosaurus and Gobisaurus is "nested deep within the ankylosaurid lineage as the first successive outgroup to (the subfamily) Ankylosaurinae". [2]
Other analyses find a more basal position as the sister species of Shamosaurus. Concluding that Zhongyuansaurus was a probable junior synonym of Gobisaurus, Arbour considered it unnecessary to use the term Shamosaurinae for the clade including just Shamosaurus and Gobisaurus. [4]
Gobisaurus in a cladogram simplified from Zheng et al. (2018): [6]
In phylogenetic analyses by Xing et al. (2024), Gobisaurus is recovered as a member of Shamosaurinae or as an ankylosaurid less derived than Shamosaurus. Below are two simplified cladograms from that study: [7]
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Nodosauridae is a family of ankylosaurian dinosaurs known from the Late Jurassic to the Late Cretaceous periods in what is now Asia, Europe, North America, and possibly South America. While traditionally regarded as a monophyletic clade as the sister taxon to the Ankylosauridae, some analyses recover it as a paraphyletic grade leading to the ankylosaurids.
Anodontosaurus is an extinct genus of ankylosaurid dinosaurs within the subfamily Ankylosaurinae. It is known from the entire span of the Late Cretaceous Horseshoe Canyon Formation of southern Alberta, Canada, and is also known from the Dinosaur Park Formation. It contains two species, A. lambei and A. inceptus.
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Talarurus is a genus of ankylosaurid dinosaur that lived in Asia during the Late Cretaceous period, about 96 million to 89 million years ago. The first remains of Talarurus were discovered in 1948 and later described by the Russian paleontologist Evgeny Maleev with the type species T. plicatospineus. It is known from multiple yet sparse specimens, making it one of the most well known ankylosaurines, along with Pinacosaurus. Elements from the specimens consists of various bones from the body; five skulls have been discovered and assigned to the genus, although the first two were very fragmented.
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This timeline of ankylosaur research is a chronological listing of events in the history of paleontology focused on the ankylosaurs, quadrupedal herbivorous dinosaurs who were protected by a covering bony plates and spikes and sometimes by a clubbed tail. Although formally trained scientists did not begin documenting ankylosaur fossils until the early 19th century, Native Americans had a long history of contact with these remains, which were generally interpreted through a mythological lens. The Delaware people have stories about smoking the bones of ancient monsters in a magic ritual to have wishes granted and ankylosaur fossils are among the local fossils that may have been used like this. The Native Americans of the modern southwestern United States tell stories about an armored monster named Yeitso that may have been influenced by local ankylosaur fossils. Likewise, ankylosaur remains are among the dinosaur bones found along the Red Deer River of Alberta, Canada where the Piegan people believe that the Grandfather of the Buffalo once lived.