| Abdarainurus | |
|---|---|
 | |
| Skeletal reconstruction with known material in white | |
Scientific classification | |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Clade: | Dinosauria |
| Clade: | Saurischia |
| Clade: | †Sauropodomorpha |
| Clade: | †Sauropoda |
| Clade: | †Macronaria |
| Clade: | †Titanosauria |
| Genus: | †Abdarainurus Averianov & Lopatin,2020 |
| Type species | |
| †Abdarainurus barsboldi Averianov & Lopatin, 2020 | |
Abdarainurus (meaning "Abdrant Nuru tail" after the holotype locality) is a genus oftitanosaurdinosaur from theAlagteeg Formation inMongolia. Thetype and only species isA. barsboldi. Currently seen as an indeterminate titanosaur, it may represent a previously unknown lineage ofAsianmacronarians.[1]Abdarainurus is not known from many remains; it is only known from eight front tail vertebrae and a middle tail vertebra and severalchevrons.
Theholotype,PIN 5669/1, was discovered in 1970 inAbdrant Nuru, hence the genus name, during a Joint Soviet–Mongolian Paleontological expedition and was excavated by V. P. Tverdokhlebov ofSaratov State University. The fossils were left unprepared until at least 2000, when paleontologist Andrei Podlesnow revealed that they probably belonged to a new genus ofsauropod.[2] The speciesAbdarainurus barsboldi was named in February 2020.[1]
Abdarainurus was discovered in the Abdarant Nuru locality of theAlagteeg Formation (which may be the same unit as the overlyingDjadochta Formation)[3] of Mongolia[1] and coexisted with theankylosaurPinacosaurus 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 ofSomphospondyli, 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 withAndesaurus andHuabeisaurus or as a member ofAeolosaurinae, respectively. AsAbdarainurus 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]
In their 2024 description ofGandititan, Hanet al. recovered it as thesister taxon toAbdarainurus, in a clade of basal titanosaurs also includingAndesaurus andHuabeisaurus, like the original analysis by Averianov & Lopatin (2020), in addition toBaotianmansaurus andDongyangosaurus, which were recovered as part of a slightly more derived clade by Averianov & Lopatin (2020).[1] The results of theirphylogenetic analyses are shown in thecladogram below:[4]
