Batyrosaurus Temporal range: Late Cretaceous, | |
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Reconstruction of Batyrosaurus | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Clade: | Dinosauria |
Clade: | † Ornithischia |
Clade: | † Neornithischia |
Clade: | † Ornithopoda |
Superfamily: | † Hadrosauroidea |
Genus: | † Batyrosaurus Godefroit et al., 2012 |
Type species | |
†Batyrosaurus rozhdestvenskyi Godefroit et al., 2012 |
Batyrosaurus is an extinct genus of herbivorous basal hadrosauroid dinosaur known from the Late Cretaceous Bostobe Formation (Santonian to Campanian stage) of central Kazakhstan. It contains a single species, Batyrosaurus rozhdestvenskyi. It is possible that Batyrosaurus represents the same taxon as the doubtful Arstanosaurus akkurganensis as both were found from the same formation. [1]
The type species Batyrosaurus rozhdestvenskyi was in 2012 named and described by Pascal Godefroit, François Escuillié, Yuri Bolotsky and Pascaline Lauters. The generic name is derived from the Batyr , the Kazakh hero warriors. The specific name honours Anatoly Konstantinovich Rozhdestvensky. [1]
The holotype, AEHM 4/1, was found near Akkurgan in a layer of the Bostobinskaya Formation dating from the Santonian-Campanian, about eighty-four millions year old. It consists of a partial skeleton, including a partial skull, the lower jaws, sixty individual teeth, the sterna, the right humerus, the left radius, metacarpals and phalanges. The authors considered Arstanosaurus akkurganensis a nomen dubium and did not refer its material. [1]
Batyrosaurus is a medium-sized hadrosauroid of about five to six metres length. Several autapomorphies, unique derived traits, were established. The parietal bones at their rear form bony flaps that overlap the supraoccipital but do not touch the sides of the paraoccipitals and are themselves overlapped by the squamosals. The frontal bones are elongated, about 70% longer than wide. The outer side of the front branch of the jugal shows a deep horizontal trough below the suture with the lacrimal. The joint surface of the surangular is pierced by a foramen. [1]
Among the material found was an about four centimetres long thumb claw. A cast was made of the braincase, showing fine arterial impressions on its inner surface, indicating it was almost completely filled by brain tissue. [1]
A cladistic analysis showed that Batyrosaurus had a basal position in the Hadrosauroidea, above Altirhinus but below Probactrosaurus in the evolutionary tree. As Tethyshadros in their analysis was a hadrosaurid, the authors considered Batyrosaurus to be the youngest known non-hadrosaurid hadrosauroid. This was seen as an indication that not only hadrosauroids but also hadrosaurids originally developed in Asia and only later migrated to North-America. [1]
Claosaurus is a genus of hadrosauroid dinosaur that lived during the Late Cretaceous Period (Santonian-Campanian).
Aralosaurus was a genus of hadrosaurid dinosaur that lived during the Late Cretaceous in what is now Kazakhstan. It is known only by a posterior half of a skull and some post-cranial bones found in the Bostobe Formation in rocks dated from the Upper Santonian-Lower Campanian boundary, at about 83.6 Ma. Only one species is known, Aralosaurus tuberiferus, described by Anatoly Konstantinovich Rozhdestvensky in 1968. The genus name means Aral Sea lizard, because it was found to the northeast of the Aral Sea. The specific epithet tuberiferus means bearing a tuber because the posterior part of the nasal bone rises sharply in front of the orbits like an outgrowth. Aralosaurus was originally reconstituted with a nasal arch similar to that of North American Kritosaurus. For many years, Aralosaurus was thus placed in the clade of the Hadrosaurinae. This classification was invalidated in 2004, following the re-examination of the skull of the animal which allowed to identify in Aralosaurus many typical characters of Lambeosaurinae. In particular, this study revealed that Aralosaurus had a hollow bony structure located far in front of the orbits, which communicated with the respiratory tract. This structure being broken at its base, its shape and size remains undetermined. More recently, Aralosaurus has been identified as the most basal Lambeosaurinae, and placed with its close relative Canardia from the upper Maastrichtian of France in the new clade of Aralosaurini.
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Amurosaurus is a genus of lambeosaurine hadrosaurid dinosaur found in the latest Cretaceous period of eastern Asia. Fossil bones of adults are rare, but an adult would most likely have been at least 6 metres (20 ft) long. According to Gregory S. Paul, it was about 8 metres (26 ft) long and weighed about 3,000 kilograms (6,600 lb).
Arstanosaurus is a genus of hadrosauroid dinosaur from the Santonian-Campanian-age Upper Cretaceous Bostobe Formation, Kazakhstan. It has had a confusing history, being considered both a hadrosaurid and a ceratopsid, or both at the same time (chimeric).
Charonosaurus is a genus of dinosaur whose fossils were discovered by Godefroit, Zan & Jin in 2000, on the south bank of the Amur River, dividing China from Russia. It is monotypic, consisting of the species C. jiayinensis.
Nipponosaurus is a lambeosaurine hadrosaur from sediments of the Yezo Group, in Sinegorsk on the island of Sakhalin, which was part of Japan at the time of the species' classification. The type and only species is N. sachalinensis, known only from a single juvenile specimen discovered in 1934 and named in 1936, by Takumi Nagao, with further material of the same individual found in 1937. Since then, the taxon has been largely ignored, and its validity has been doubted, with synonymy with other Asian hadrosaurs or status as a nomen dubium being suggested. Redescriptions from 2004 and 2017, however, have supported recognition as a distinct species. Dating the only specimen has been difficult, but based on associated mollusc taxa, the species likely lived sometime in the upper Santonian or lower Campanian, around 80 million years ago.
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Wulagasaurus is a genus of saurolophine hadrosaurid dinosaur from the Late Cretaceous of Heilongjiang, China.
Sahaliyania is a genus of lambeosaurine hadrosaurid dinosaur from the Late Cretaceous of Heilongjiang, China.
The Bostobe Formation is a geological formation in Qaraghandy & Qyzylorda, Kazakhastan whose strata date back to the Late Cretaceous.
The Udurchukan Formation is a geological formation located in Amur Region, Far East Russia. Based on palynomorphs such as Wodehouseia spinata, the Udurchukan is considered of Maastrichtian age of the Late Cretaceous, during the Cretaceous Period.
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Samrukia is a genus of large Cretaceous pterosaurs known only from a single lower jaw discovered in Kazakhstan. The holotype and only known specimen was collected from the Santonian-Campanian age Bostobynskaya Formation in Kyzylorda District. It was described by Darren Naish, Gareth Dyke, Andrea Cau, François Escuillié, and Pascal Godefroit in 2012, and the type species is named Samrukia nessovi. The species is named after Lev Nessov, a paleontologist, and the genus is named after Samruk, a magical bird of Kazakh folklore.
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