A re-evaluation of sphenacodontid synapsid material from the Lower Permian fissure fills near Richards Spur, Oklahoma

52 1 January 219 227 10.1111/j.1475-4983.2008.00837.x

EVANS, D. C., MADDIN, H. C., REISZ, R. R. 2009. A re-evaluation of sphenacodontid synapsid material from the Lower Permian fissure fills near Richards Spur, Oklahoma. Palaeontology, 52, 1, 219–227.

David C. Evans, Hillary C. Maddin and Robert R. Reisz Early Permian terrestrial vertebrate faunal assemblages of Laurasia are dominated by large ophiacodontid, sphenacodontid, and edaphosaurid synapsids. This pattern contrasts with the fauna recovered from the Early Permian fissure fill deposits near Richards Spur, Oklahoma, where derived nontherapsid synapsids are rare. The fragmentary remains of Thrausmosaurus serratidens constitute the only published report of Sphenacodontidae from this locality. Here, we re-evaluate T. serratidens in light of new information on the faunal assemblage of this locality. We confirm that the type material of T. serratidens cannot be assigned to Sphenacodontidae and conclude that it pertains to an indeterminate varanopid. We also describe new material, including a partial maxilla, several isolated jaw fragments with teeth, an isolated precaniniform tooth and a posterior cervical vertebra that represents unequivocal sphenacodontid remains from the Richards Spur assemblage. This material is the first definitive record of a eupelycosaurian synapsid other than a varanopid from this important locality. Faunal similarities between Richards Spur and the Bromacker Quarry, Germany, may be reflective of upland terrestrial communities during the Early Permian.
  • ANDERSON, J. S. and REISZ, R. R. 2003. A new microsaur (Tetrapoda: Lepospondyli) from the Lower Permian of Richards Spur (Fort Sill), Oklahoma. Canadian Journal of Earth Sciences, 40, 499–505.
  • BERMAN, D. S., REISZ, R. R., BOLT, J. R. and SCOTT, D. 1995. The cranial anatomy and relationships of the synapsid Varanosaurus (Eupelycosauria: Ophiacodontidae) from the Early Permian of Texas and Oklahoma. Annals of Carnegie Museum, 64, 99–133.
  • BERMAN, D. S., REISZ, R. R., SCOTT, D., HENRICI, A. C., SUMIDA, S. S. and MARTENS, T. 2000. Early Permian bipedal reptile. Science, 290, 969–972.
  • BERMAN, D. S., REISZ, R. R., MARTENS, T. and HENRICI, A. C. 2001. A new species of Dimetrodon (Synapsida: Sphenacodontidae) from the Lower Permian of Germany records the first occurrence of the genus outside of North America. Canadian Journal of Earth Sciences, 38, 803–812.
  • BERMAN, D. S., HENRICI, A. C., SUMIDA, S. S. and MARTENS, T. 2004. New materials of Dimetrodon teutonis (Synapsida: Sphenacodontidae) from the Lower Permian of Germany. Annals of Carnegie Museum, 73, 108–116.
  • BOLT, J. R. 1980. New tetrapods with bicuspid teeth from the Fort Sill locality (Lower Permian, Oklahoma). Neues Jahrbuch für Geologie und Palontologie, Monatshefte, 8, 449–459.
  • CARROLL, R. L. 1968. A ?diapsid (Reptilia) parietal from the lower Permian of Oklahoma. Postilla, 117, 1–7.
  • CURRIE, P. J. 1977. A new haptodontine sphenacodont (Reptilia: Pelycosauria) from the Upper Pennsylvanian of North America. Journal of Paleontology, 51, 927–942.
  • CURRIE, P. J., RIGBY, J. K. Jr and SLOAN, R. E. 1990. Theropod teeth from the Judith River Formation of southern Alberta, Canada. 107–125. In CARPENTER, K. and CURRIE, P. J. (eds). Dinosaur systematics: perspectives and approaches. Cambridge University Press, Cambridge, 318 pp.
  • EBERTH, D. A. 1985. The skull of Sphenacodon ferocior, and comparison with other sphenacodontines (Reptilia: Pelycosauria). New Mexico Bureau of Mines and Mineral Resources Circular, 190, 5–39.
  • EBERTH, D. A., BERMAN, D. S., SUMIDA, S. S. and HOPF, H. 2000. Lower Permian terrestrial paleoenvironments and vertebrate paleoecology of the Tambach Basin (Thuringia, central Germany): the upland holy grail. Palaios, 15, 293–313.
  • FIORILLO, A. R. and CURRIE, P. J. 1994. Theropod teeth from the Judith River Formation (Upper Cretaceous) of south-central Montana. Journal of Vertebrate Paleontology, 14, 74–80.
  • FIORILLO, A. R. and GANGLOFF, R. A. 2000. Theropod teeth from the Prince Creek Formation (Cretaceous) of Northern Alaska, with speculations on Arctic dinosaur paleoecology. Journal of Vertebrate Paleontology, 20, 675–682.
  • FOX, R. C. 1962. Two new pelycosaurs from the Lower Permian of Oklahoma. University of Kansas Museum of Natural History Publications, 12, 297–307.
  • KEMP, T. S. 1982. Mammal-like reptiles and the origin of mammals. Academic Press, London, 363 pp.
  • KISSEL, R. A., DILKES, D. W. and REISZ, R. R. 2002. Captorhinus magnus, a new captorhinid (Amniota: Eureptilia) from the Lower Permian of Oklahoma, with new evidence on the homology of the astragalus. Canadian Journal of Earth Sciences, 39, 1363–1372.
  • LAURIN, M. 1993. Anatomy and relationships of Haptodus garnettensis, a Pennsylvanian synapsid from Kansas. Journal of Vertebrate Paleontology, 13, 200–229.
  • MADDIN, H. C., EVANS, D. C. and REISZ, R. R. 2006. An Early Permian varanodontine varanopid (Synapsida: Eupelycosauria) from the Richards Spur locality, Oklahoma. Journal of Vertebrate Paleontology, 26, 957–966.
  • MAY, W. J. and CIFELLI, R. L. 1998. Baeotherates fortsillensis, a new captorhinid reptile from the Fort Sill fissures, Lower Permian of Oklahoma. Oklahoma Geology Notes, 58, 128–137.
  • MODESTO, S. P. 1996. A basal captorhinid reptile from the Fort Sill fissures, Lower Permian of Oklahoma. Oklahoma Geology Notes, 56, 4–14.
  • MODESTO, S. P. 1998. New information on the skull of the Early Permian reptile Captorhinus aguti. PaleoBios, 18, 21–35.
  • MODESTO, S. P. 1999. Colobomycter pholeter from the Lower Permian of Oklahoma: a parareptile, not a protorothyridid. Journal of Vertebrate Paleontology, 19, 466–472.
  • MODESTO, S. P., SIDOR, C. A., RUBIDGE, B. S. and WELMAN, J. 2001. A second varanopseid skull from the Upper Permian of South Africa: implications for Late Permian ‘pelycosaur’ evolution. Lethaia, 34, 249–259.
  • MÜLLER, J., BERMAN, D. S., HENRICI, A. C., MARTENS, T. and SUMIDA, S. S. 2006. The basal reptile Thuringothyris mahlendorffae (Amniota: Eureptilia) from the Lower Permian of Germany. Journal of Paleontology, 80, 726–739.
  • OSBORN, H. F. 1903. On the primary division of the Reptilia into two sub-classes, Synapsida and Diapsida. Science, 17, 275–276.
  • REISZ, R. R. 1980. A protorothyridid captorinomorph reptile from the Lower Permian of Oklahoma. Royal Ontario Museum Life Sciences Contributions, 121, 1–16.
  • REISZ, R. R. 1986. Pelycosauria. In WELLNHOFER, P. (ed.). Handbuch der Palaoherpetologie, Teil 17A. Gustav Fischer Verlag, Stuttgart, 102 pp.
  • REISZ, R. R. 1997. The origin and early evolutionary history of amniotes. Trends in Ecology and Evolution, 12, 218–222.
  • REISZ, R. R. 2005. Oromycter, a new caseid from the Lower Permian of Oklahoma. Journal of Vertebrate Paleontology, 25, 905–910.
  • REISZ, R. R. and BERMAN, D. S. 2001. The skull of Mesenosaurus romeri, a small varanopseid (Synapsida: Eupelycosauria) from the Upper Permian of the Mesen River Basin, Northern Russia. Annals of Carnegie Museum, 70, 113–132.
  • REISZ, R. R. and SUTHERLAND, T. 2001. A diadectid (Tetrapoda: Diamectomorpha) from the Lower Permian fissure fills of the Dolese Quarry, near Richards Spur, Oklahoma. Annals of Carnegie Museum, 70, 133–142.
  • REISZ, R. R. and LAURIN, M. 2004. A reevaluation of the enigmatic Permian synapsid Watongia and of its stratigraphic significance. Canadian Journal of Earth Sciences, 41, 377–386.
  • REISZ, R. R. and MODESTO, S. P. 2007. Heleosaurus scholtzi from the Permian of South Africa: a varanopid synapsid, not a diapsid reptile. Journal of Vertebrate Paleontology, 70, 734–739.
  • REISZ, R. R., BERMAN, D. S. and SCOTT, D. 1992. The cranial anatomy and relationships of Secodontosaurus, an unusual mammal-like reptile (Synapsida: Sphenacodontidae) from the Early Permian of Texas. Zoological Journal of the Linnean Society, 104, 127–184.
  • REISZ, R. R., WILSON, H. and SCOTT, D. 1997. Varanopseid synapsid skeletal elements from Richards Spur, a Lower Permian fissure fill located near Fort Sill, Oklahoma. Oklahoma Geology Notes, 57, 160–170.
  • REISZ, R. R., BARKAS, V. and SCOTT, D. 2002. A new Early Permian bolosaurid from the Richards Spur Dolese Brothers Quarry, near Fort Sill, Oklahoma. Journal of Vertebrate Paleontology, 22, 23–28.
  • ROMER, A. S. and PRICE, L. I. 1940. Review of the Pelycosauria. Geological Society of America, Special Papers, 28, 1–538.
  • SULLIVAN, C. and REISZ, R. R. 1999. First record of Seymouria (Vertebrata: Seymouriamorpha) from Early Permian fissure fills at Richards Spur, Oklahoma. Canadian Journal of Earth Sciences, 36, 1257–1266.
  • WILLISTON, S. W. 1912. Primitive reptiles. Journal of Morphology, 23, 637–666.
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