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Kunpania is an extinct genus of dicynodont therapsid from the Quanzijie Formation of Xinjiang, China. The type species and only species is K. scopulusa, and it is known only by a single incomplete specimen including parts of the skull and forelimb. Since its initial description in 1978 by palaeontologist Ailing Sun, it has sometimes been considered to be another species of Dicynodon by other researchers, or potentially undiagnostic. However, a redescription in 2021 reaffirmed its distinctiveness, including a uniquely well developed muscle attachment on the humerus. Kunpania is perhaps the oldest known member of the derived dicynodont group Dicynodontoidea, potentially dating to the Middle Permian period during the Capitanian, and so may fill a knowledge gap in the history of dicynodont evolution.
Kunpania was first described in 1978 by palaeontologist Ailing Sun from the type specimen and only known specimen IVPP V4695. The specimen originally only consisted of a partial snout missing the tip, a broken lower jaw and part of the forelimb including the right scapula, coracoid plate and humerus. Additionally, a partial right clavicle and a piece of the left tibia with the same specimen number were later recovered from the Institute of Vertebrate Paleontology and Paleoanthropology collections that matched the preservation style of the holotype, and so likely belong to the same specimen. In 1998 and 2001, palaeontologist Spencer G. Lucas synonymised Kunpania into Dicynodon as a distinct species, D. scopulusa, though he later considered the species to be dubious (a nomen dubium) in 2005.S. G. Lucas (2025). 023108482X, Columbia University Press. 023108482X The species was again considered valid by Jörg Fröbisch in 2009, who again regarded it as a species of Dicynodon. In their 2011 revision of the taxonomy of Dicynodon, palaeontologists Christian Kammerer, Kenneth Angielczyk, and Fröbisch tentatively concluded that 'D.' scopulusa may be a valid taxon, but that its status was ultimately uncertain owing to its incompleteness.
Kunpania was fully redescribed in 2021 by Angielczyk, Jun Liu and Wan Yang, including further preparation of the underside of the skull that revealed additional features. Angielczyk and colleagues concluded that Kunpania was indeed a wholly distinct genus and species of dicynodont based on a unique combination of physical traits and comparisons with other dicynodonts.
The secondary palate on the roof of the mouth, composed of the bones, is unusually smooth in Kunpania, with only a single midline ridge at the back. The crista oseophagea, a bony process of the Pterygoid bone on the roof of the mouth, is unusually robust and blocky, unlike the blade-like structure more typical of bidentalians and more like those of more primitive dicynodonts.
The mandible resembles those of other dicynodonts, with a squared-off beak that is upturned at the tip. The lateral dentary shelf, a site for jaw muscle attachment, is well developed and overhangs the mandibular fenestra. The shelf is unusually thick compared to other Dicynodontoidea, and is angled outwards in a triangular shape from above, more similar to its shape in the unrelated Dicynodontoides (a non-dicynodontoid dicynodont). Just behind the mandibular fenestra, there is an unusual backwards-curving ridge on the angular bone. This ridge sits where the reflected lamina (a bony structure potentially used in hearing) usually attaches in other dicynodonts, however they are usually attached by a vertical ridge, unlike the horizontally curving structure in Kulpania. The reflected lamina may then have been unusually shaped.
The cladogram produced by Angielczyk et al. (2021) is reproduced and simplified below:
Kunpania is diagnosed by the absence of ridges on the palate at the front of the mouth, a robust and block-like crista oseophagea, a prominent and thick lateral dentary shelf on the lower jaw, a small backwards-curving projection of the angular bone, and the large, triangular shaped attachment for the latissimus dorsi on the humerus.
Alternatively, an early to middle Wuchiapingian age would be more consistent with the known record of bidentalian dicynodonts, being a contemporary of early Cryptodontia and still the oldest known dicynodontoid. The latter is also in keeping with its relatively basal phylogenetic position and would fill the ghost lineage between derived dicynodontoids and cryptodonts. This scenario would suggest bidentalians originated before the end-Capitanian extinction but only radiated afterwards, rapidly spreading across Pangaea to Laurasia and Gondwana. A third hypothesis, that Kunpania is mid-late Wuchiapingian in age, would result in no change to the known pattern of bidentalian evolution. It would also require that the age of the upper Quanzijie Formation to be significantly underestimated and drastically shorten the period of time between it and the overlying Guodikeng Formation.
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