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| Kuru kulla Napoli, Ruebenstahl, Bhullar, Turner & Norell, 2021 DOI: 10.1206/3982.1 |
Abstract
Dromaeosaurid theropods represent a rare but important clade of nonavialan dinosaurs. Their close evolutionary relationship to modern birds has placed them at the center of paleontological research for the last several decades. Herein we describe a new species of dromaeosaurid—Kuru kulla, gen. et sp. nov.—based on a partial skeleton from the Late Cretaceous Khulsan locality (Barun Goyot Formation) of Mongolia. This species is diagnosed by several autapomorphies within Dromaeosauridae, including a sharp groove anterior and ventral to the narial fossa on the premaxilla, a posterolaterally directed hornlet on the posterodorsal process of the lacrimal, a deep surangular bearing two surangular foramina, and anteriorly displaced pleurocoels on the dorsal centra. The taxon is further characterized by a unique combination of characters, including a mediolaterally narrow metatarsal II, serrations on both carinae of the dentary teeth, hyposphenes that are widely separated but joined by a web of bone, and a lacrimal with a poorly developed boss on its lateral surface. Phylogenetic analysis finds Kuru kulla to be the sister taxon of Adasaurus mongoliensis, from the slightly later Nemegt Formation, with which it is united by three synapomorphies: a posterior surangular foramen that is ∼30% the depth of the surangular, absence of a fourth trochanter of the femur, and thoracic centra that are markedly longer than their midpoint widths. The recognition of this taxon has important implications for common assumptions of Mesozoic terrestrial ecosystem structure and adds new data to a recently recognized pattern in dromaeosaurid faunal composition among Late Cretaceous localities in Mongolia and Inner Mongolia (Nei Mongol Autonomous Region, China).
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| Kuru kulla Right dentary of IGM 100/981, showing all fragments in life position, in lateral view. |
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| Tangka depicting Kurukullā from the Hall of Asian Peoples, American Museum of Natural History. |
Dinosauria Owen, 1843
Theropoda Marsh, 1881
Coelurosauria Huene, 1920
Maniraptora Gauthier, 1986
Dromaeosauridae Matthew and Brown, 1922
Kuru kulla, gen. et sp. nov
Etymology: Kurukullā (fig. 1) is a deity venerated in Tibetan Buddhism. Considered peaceful to semiwrathful, she is usually depicted with four arms, holding in one pair of hands a bow and arrow, and in the other pair a hook and noose, all of which are made of flowers. Kurukullā is particularly associated with major life transitions. We emphasize here that the generic name Kuru is not in reference to the cannibalism-borne prion disease of the same name.
SUMMARY:
Kuru kulla is a new species of velociraptorine dromaeosaurid from the Barun Goyot Formation at Khulsan. It is the first velociraptorine to be recognized from a locality and stratum that has previously yielded a different velociraptorine species, in this case, the recently described Shri devi (Turner et al., 2021). As such, it provides important insight into the structure of Late Cretaceous nonavian dinosaur-bearing faunas. Kuru kulla demonstrates that similar, closely related dinosaur species could and did coexist, contrary to general expectations that such species would not tolerate each other due to competitive exclusion (Molnar, 1990). This has ramifications for the taxonomic referral of new fossil material and argues strongly for an apomorphy-based (rather than similarity- and provenance-based) approach to referral.
James G. Napoli, Alexander A. Ruebenstahl, Bhart-Anjan S. Bhullar, Alan H. Turner and Mark A. Norell. 2021. A New Dromaeosaurid (Dinosauria: Coelurosauria) from Khulsan, Central Mongolia. American Museum Novitates. (3982); 1-47. DOI: 10.1206/3982.1
