Phylogenetic history of Auroraceratops rugosus (Ceratopsia: Ornithischia) from the Lower Cretaceous of Gansu Province, China

Abstract

Basal neoceratopsians are a relatively diverse group of small- to medium-sized herbivorous dinosaurs from the Early to Late Cretaceous of Asia and North America. Although known for over a century, this group has only relatively recently received intense independent study, tied to the rapid increase in known diversity since 1997. Auroraceratops rugosus is one of these recently discovered species and is one of the best-known basal neoceratopsians, being represented by over 80 specimens, and is also the most completely represented neoceratopsian from the Early Cretaceous. A phylogenetic analysis focusing on non-ceratopsid ceratopsians examines the phylogenetic context of Auroraceratops. The analysis is based on a new matrix of 41 taxa and 257 characters. The results recover an Auroraceratops-Aquilops-ZPAL MgD-I/156 clade within basal Neoceratopsia that is sister to a clade composed of Asiaceratops, Yamaceratops, Mosaiceratops, and the larger clades Leptoceratopsidae and Coronosauria. This phylogeny recovers a monophyletic Coronosauria, Leptoceratopsidae, and Protoceratopsidae. Helioceratops is recovered as sister to the rest of Leptoceratopsidae, Ischioceratops is recovered nested within Leptoceratopsidae, and the enigmatic genus Mosaiceratops is recovered as a basal neoceratopsian, sister to Yamaceratops. Yinlong, and Hualianceratops are recovered in an expanded Chaoyangsauridae, and the genus Psittacosaurus is recovered as the earliest diverging lineage in Ceratopsia. Ajkaceratops, the only European ceratopsian, is robustly recovered as sister to the rest of Ceratopsoidea.

SUPPLEMENTAL DATA—Supplemental materials are available for this article for free at www.tandfonline.com/UJVP

Citation for this article: Morschhauser, E. M., H. You, D. Li, and P. Dodson. 2019. Phylogenetic history of Auroraceratops rugosus (Ceratopsia: Ornithischia) from the Lower Cretaceous of Gansu Province, China; pp. 117–147 in Hailu You, Peter Dodson, and Eric Morschhauser (eds.), Auroraceratops rugosus (Ornithischia, Ceratopsia) from the Early Cretaceous of northwestern Gansu Province, China. Society of Vertebrate Paleontology Memoir 18. Journal of Vertebrate Paleontology 38(Supplement). DOI: 10.1080/02724634.2017.1509866.

ACKNOWLEDGMENTS

We would like to thank the following researchers for generously sharing research photographs of specimens we were unable to visit in person: Y.-N. Lee for Koreaceratops, J. Kirkland and M. Loewen for Diabloceratops, P. Makovicky for Udanoceratops, and K. Tanoue for Chaoyangsaurus. We thank the Willi Hennig Society for supporting the free use of TNT. We would like to thank M. Wilkinson for making TAXEQ3 freely available and M. Bell and G. Lloyd for their clear documentation of Strap. We thank C. Mehling and M. Norell (AMNH), X. Xu (IVPP), J. Horner and J. Scanella (MOR), M. Brett-Surman and C. Ito (USNM), K. Shepard and C. Kennedy (CMN), A. Folie, P. Godefroit, and H. du Potter (IRSNB), S. Maidment, S. Chapman, and P. Barrett (NHMUK), D. Brinkman (YPM), X. Jin (ZMNH), R. McCord (AZMNH), M. Borsuk-Bialyicka and R. Bronowicz (ZPAL), and B. Stirilisky (RTMP) for access to specimens under their care and hospitality during our visits. This work began as a component of a doctoral dissertation in the Department of Earth and Environmental Science at the University of Pennsylvania. We thank H. Pfferkorn and A. Tumarkin-Deratzian for reading an earlier draft of this work. We thank A. Farke and D. Evans for their reviews and R. Irmis for his patient editorial work that improved this contribution. This research was generously funded by a National Geographic Young Explorer’s Grant (8930-11), several Penn Paleobiology Summer Stipend grants (2009–2010), a Jurassic Foundation grant, and a grant from the Evolving Earth Foundation to E.M.M. A portion of this work was completed while E.M.M. was participating in the 2009 National Science Foundation/Ministry of Science and Technology (NSF/MoST) East Asia and Pacific Summer Institutes program (OISE-0913833). This research was also generously funded by grants from the National Science Foundation (1024671) to P.D. and H.Y., the National Natural Science Foundation of China (41072019) and the Hundred Talents Project of the Chinese Academy of Sciences to H.Y., and the Gansu Geological Museum to L.D.