''Abdarainurus'' (meaning "Abdrant Nuru tail" after the holotype locality) is a genus of titanosaur dinosaur from the

Alagteeg Formation The Alagteeg Formation is a geological formation in Mongolia whose strata date back to the Late Cretaceous. Dinosaur remains are among the fossils that have been recovered from the formation.Weishampel et al., 2004, pp.593-600 It predominantly cons ...

in Mongolia. The

type Type may refer to: Science and technology Computing * Typing, producing text via a keyboard, typewriter, etc. * Data type, collection of values used for computations. * File type * TYPE (DOS command), a command to display contents of a file. * Ty ...

and only species is ''A. barsboldi''. Currently seen as an indeterminate titanosaur, it may represent a previously unknown lineage of Asian macronarians. ''Abdarainurus'' is not known from many remains; it is only known from eight front tail vertebrae and a middle tail vertebra and several chevrons.

Discovery and naming

The holotype, PIN 5669/1, was discovered in 1970 in Abdrant Nuru, hence the genus name, during a Joint Soviet–Mongolian Paleontological expedition and was excavated by V. P. Tverdokhlebov of

Saratov State University Saratov Chernyshevsky State University (russian: Саратовский государственный университет имени Н. Г. Чернышевского, СГУ, transcribed as SGU) is a major higher education and research inst ...

. The fossils were left unprepared until at least 2000, when paleontologist Andrei Podlesnow revealed that they probably belonged to a new genus of

sauropod Sauropoda (), whose members are known as sauropods (; from '' sauro-'' + '' -pod'', 'lizard-footed'), is a clade of saurischian ('lizard-hipped') dinosaurs. Sauropods had very long necks, long tails, small heads (relative to the rest of their bo ...

. The species ''Abdarainurus barsboldi'' was named in February 2020.

Paleoecology

''Abdarainurus'' was discovered in the Abdarant Nuru locality of the

(which may be the same unit as the overlying Djadochta Formation) of Mongolia and coexisted with the

ankylosaur Ankylosauria is a group of herbivorous dinosaurs of the order Ornithischia. It includes the great majority of dinosaurs with armor in the form of bony osteoderms, similar to turtles. Ankylosaurs were bulky quadrupeds, with short, powerful limbs. ...

'' Pinacosaurus'' sp., and indeterminate turtles and dinosaurs.

Classification

''Abdarainurus'' was added to the phylogenetic analysis of Mannion and colleagues by Averianov and Lopatin, who ran the matrix under three different conditions. With all characters treated as equally important, ''Abdarainurus'' resolved as a non-titanosaur member of Somphospondyli, in a large polytomy with a variety of taxa. The more labile characters treated as slightly, or significantly, less important, ''Abdarainurus'' was either a basal titanosaur in a clade with '' Andesaurus'' and ''

Huabeisaurus ''Huabeisaurus'' (, meaning " North China lizard") was a genus of dinosaur from the Late Cretaceous ( Cenomanian to Maastrichtian stages, around 99.7–70.6 million years ago). It was a sauropod which lived in what is present-day northern Chin ...

'' or as a member of Aeolosaurinae, respectively. As ''Abdarainurus'' was resolved with the fewest unique features as a basal titanosaur, Averianov and Lopatin suggested that phylogenetic result was the most likely, shown below. Abdarainurus Size Comparison

References

Titanosaurs Late Cretaceous dinosaurs of Asia Fossil taxa described in 2020 {{sauropodomorph-stub