A new species of the parareptile genus Delorhynchus, based on articulated skeletal remains from Richards Spur, Lower Permian of Oklahoma

ABSTRACT

Description of a new species of the parareptile genus Delorhynchus is based on a well-preserved partial subadult skeleton, an isolated adult skull, and disarticulated elements recently collected from the Lower Permian Richards Spur locality of Oklahoma, U.S.A. Delorhynchus cifellii, sp. nov., is distinguished from Delorhynchus priscus by the lack of an accessory articulating anterodorsal flange of the maxilla. The hypodigm of Delorhynchus cifellii reveals that Delorhynchus is distinguished from other parareptiles by cranial dermal sculpture consisting of a system of low, smooth tuberosities and a pattern of diffuse shallow, circular dimples. In a phylogenetic analysis of parareptiles, Delorhynchus cifellii is positioned as the sister species of Lanthanosuchoidea. Recognition of Delorhynchus cifellii, sp. nov., and its phylogenetic position among parareptiles highlights the significance of the Richards Spur locality in our understanding of the early evolutionary history of reptiles.

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

ACKNOWLEDGMENTS

We thank R. Cifelli, J. Larsen, and W. J. May for specimen loans and hosting our visits to the OMNH, and D. Scott for photography and for the specimen illustrations. R.R.R. is supported by a Discovery Grant from the Natural Sciences and Engineering Research Council (NSERC) of Canada. S.P.M. is supported by a New Opportunities Fund Award from the Canadian Foundation for Innovation, and by a grant from the Nova Scotia Research and Innovation Trust.

Handling editor: Bruce Rubidge