A new reptile from the Richards Spur locality, Oklahoma, U.S.A., and patterns of Early Permian parareptile diversification

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 <i>Colobomycter pholeter</i>. 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 <i>Colobomycter</i>. This new material differs from that of <i>C. pholeter</i> in that it possesses at least three more teeth on its maxilla, the enlarged premaxillary and maxillary teeth are more gracile than those in <i>C. pholeter</i>, 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 <i>Colobomycter vaughni</i>, sp. nov. The discovery of <i>C. vaughni</i> 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. http://zoobank.org/urn:lsid:zoobank.org:pub:149450CF-4CB8-4099-B037-7E371A5AB286 SUPPLEMENTAL DATA—Supplemental materials are available for this article for free at www.tandfonline.com/UJVP Citation for this article: MacDougall, M. J., S. P. Modesto, and R. R. Reisz. 2016. A new reptile from the Richards Spur locality, Oklahoma, U.S.A., and patterns of Early Permian parareptile diversification. Journal of Vertebrate Paleontology. DOI: 10.1080/02724634.2016.1179641.下二叠统理查德斯普尔（Richards Spur）产地是目前已知物种最丰富的古生代陆生脊椎动物组合，该产地产出的四足类（tetrapod）多样性中，有相当大的比例由副爬行动物（parareptiles）构成。首个被描述的理查德斯普尔副爬行动物为<i>Colobomycter pholeter</i>。该物种以其膨大的前颌齿与成对膨大的上颌齿为特征，其独特的齿列使其外观与理查德斯普尔产地的其他副爬行动物截然不同。本文记述了产自理查德斯普尔产地中可归入<i>Colobomycter</i>的新颅骨材料。该新材料与<i>C. pholeter</i>的标本存在三点差异：其一，其上颌骨至少多了三颗牙齿；其二，膨大的前颌齿与上颌齿比<i>C. pholeter</i>的更为纤细；其三，泪骨（lacrimal）仅局限于眼眶外缘，并无额外的侧部暴露。本文认为这些差异足以确立独立物种地位，故将该新化石命名为<i>Colobomycter vaughni</i>，sp. nov.（新种）。<i>C. vaughni</i>在理查德斯普尔产地的发现具有重要学术价值，其证实了俄克拉荷马州境内存在另一种兰塔诺蜥超科（Lanthanosuchoidea）演化支成员，使其成为该州发现的第六个该类群物种。俄克拉荷马州境内该演化支的众多类群表明，早二叠世时期，劳拉西亚（Laurasia）西部这片区域曾是小型掠食性兰塔诺蜥超科动物的辐射演化中心。 http://zoobank.org/urn:lsid:zoobank.org:pub:149450CF-4CB8-4099-B037-7E371A5AB286 补充数据：本文可免费获取补充材料，网址为www.tandfonline.com/UJVP 本文引用信息：MacDougall, M. J., S. P. Modesto, R. R. Reisz. 2016. 美国俄克拉荷马州理查德斯普尔产地的新爬行动物与早二叠世副爬行动物的演化模式。《脊椎动物古生物学杂志》。DOI: 10.1080/02724634.2016.1179641.