Abdarainurus

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. The fossils were left unprepared until at least 2000, when paleontologist Andrei Podlesnow revealed that they probably belonged to a new genus of sauropod.[2] The species Abdarainurus barsboldi was named in February 2020.[1]

Abdarainurus was discovered in the Abdarant Nuru locality of the Alagteeg Formation (which may be the same unit as the overlying Djadochta Formation)[3] of Mongolia[1] and coexisted with the ankylosaur Pinacosaurus sp., and indeterminate turtles and dinosaurs.

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 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.[1]

Hypothetical reconstruction/size comparison of Abdarainurus with human for reference