Colobomycter vaughni: a new Lanthanosuchoid Parareptile From Early Permian Oklahoma

A new reptile from the Richards Spur Locality, Oklahoma, USA, and patterns of Early Permian parareptile diversification

Authors:

MacDougall et al

Abstract:

The Lower Permian Richards Spur locality is the most speciose Paleozoic continental vertebrate assemblage currently known, and a significant proportion of the tetrapod diversity found at the locality is made up of parareptiles. The first Richards Spur parareptile to be described was Colobomycter pholeter. It has been characterized by its enlarged premaxillary tooth and paired enlarged maxillary teeth, unique dentition that grants it an appearance quite distinct from other parareptiles at Richards Spur. Here we describe new cranial material from Richards Spur that is referable to Colobomycter. This new material differs from that of C. pholeter in that it possesses at least three more teeth on its maxilla, the enlarged premaxillary and maxillary teeth are more gracile than those in C. pholeter, and the lacrimal is restricted externally to the orbital margin and does not exhibit an extra lateral exposure. We infer that these differences merit specific distinction and assign the new fossil to Colobomycter vaughni, sp. nov. The discovery of C. vaughni at Richards Spur is important, because it reveals the presence of another member of the clade Lanthanosuchoidea in Oklahoma, making it the sixth to be found in the state. The large number of taxa from this clade found in Oklahoma suggests that during the Early Permian, this area of western Laurasia was the center of a radiation of small, predatory lanthanosuchoids.

Delorhynchus cifellii: a new Lanthanosuchoid Parareptile From Sakmarian Permian Oklahoma

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

Authors:

Reisz et al

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.