Khulsanurus is known from a holotype containing partial vertebral series of the neck and tail, scapulocoracoids, a right humerus, a possible left humerus, and a left pubis. Distinguishing autapomorphies of this specimen include pleurocoel-, carotid process-, and epipophysis-less cervical vertebrae, prominent infrapostzygapophyseal fossa of the caudal vertebrae which also bear anteriorly pointing prezygapophyses.[1]
Classification
Averianov & Lopatin (2021) placed Khulsanurus in a polytomy with Albinykus, Ceratonykus, Linhenykus, Parvicursor, Xixianykus, Qiupanykus, Nemegtonykus, PIN 5838/1 (=Ondogurvel) and a clade containing Shuvuuia and Mononykus in a strict consensus tree using unweighted characters. However, Averianov & Lopatin (2021) also recovered it in a polytomy with only Albinykus, Xixianykus, PIN 5838/1 (=Ondogurvel), Mononykus and Shuvuuia in a consensus tree using implied weighting.[1] Averianov & Sues (2022) conducted a phylogenetic analysis using implied weighting which recovered it in a similar position but with inclusion of a clade containing Linhenykus, Ceratonykus and Parvicuror and the exclusion of Qiupanykus and Nemegtonykus, while a 50% majority rule tree from the same analysis placed it within a polytomy with two clades.[2]
A phylogenetic analysis conducted by Averianov & Sues (2022) is reproduced below.[2]
^ abcAverianov AO, Lopatin AV (2022). "The second taxon of alvarezsaurid theropod dinosaurs from the Late Cretaceous Khulsan locality in Gobi Desert, Mongolia". Historical Biology: An International Journal of Paleobiology. 34 (11): 2125–2136. doi:10.1080/08912963.2021.2000976. S2CID244421277.
^ abAverianov AO, Sues HD (2022). "New material and diagnosis of a new taxon of alvarezsaurid (Dinosauria, Theropoda) from the Upper Cretaceous Bissekty Formation of Uzbekistan". Journal of Vertebrate Paleontology. 41 (5): e2036174. doi:10.1080/02724634.2021.2036174. S2CID247391327.
^Carpenter, K., Hayashi, S., Kobayashi, Y., Maryańska, T., Barsbold, R., Sato, K., and Obata, I., 2011, "Saichania chulsanensis (Ornithischia, Ankylosauridae) from the Upper Cretaceous of Mongolia", Palaeontographica, Abteilung A, 294(1-3): 1-61
^Penkalski, P.; Tumanova, T. (2017). "The cranial morphology and taxonomic status of Tarchia (Dinosauria: Ankylosauridae) from the Upper Cretaceous of Mongolia". Cretaceous Research. 70: 117−127. Bibcode:2017CrRes..70..117P. doi:10.1016/j.cretres.2016.10.004.
^Kurzanov, S. M. (1990). "A new Late Cretaceous protoceratopsid genus from Mongolia". Paleontological Journal. 24: 85−91.