Gnathodus

Belongs within: Spathognathodontidae.

Gnathodus is a genus of conodonts known from the Lower Carboniferous. Members of the genus bore conspicuously asymmetric Pa elements with nodes on the upper surface commonly forming a parapet (Sweet 1988).

Characters (from Sweet 1988): Pa elements conspicuously asymmetric; anterior end of cup on concave (“inner”) side of element invariably joining blade well anterior to anterior end of cup on convex (“outer”) side; nodes on upper surface of inner cup segment commonly joining to form distinctive ridge- or comblike parapet; outer cup commonly more broadly expanded than inner one.

<==Gnathodus Pander 1856S88 [incl. Dryphenotus Cooper 1939H62, Westfalicus Schmidt in Moore & Sylvester-Bradley 1957M62]
    |--G. cuneiformisS88
    `--+--G. delicatusS88
       `--+--G. typicus Cooper 1939S88, WM03
          `--+--G. punctatusS88
             `--+--G. semiglaberS88
                `--+--G. pseudosemiglaberS88
                   `--G. texanusS88
Gnathodus incertae sedis:
  *G. mosquensis Pander 1856M62
  G. austini Belka 1985S88
  G. bilineatus Roundy 1926AS93
  G. girtyiS88
    |--G. g. girtyiR79
    `--G. g. simplexR79
  G. integer Schmidt 1934 [=*Westfalicus integer]M62
  G. praebilineatus Belka 1985S88
  G. pustulosusH62
  G. scotiaensisS88
  G. simplicatusS88
  G. subblineatusS88
  G. symmutatusS88

*Type species of generic name indicated

References

[AS93] Aldridge, R. J., & M. P. Smith. 1993. Conodonta. In: Benton, M. J. (ed.) The Fossil Record 2 pp. 563–572. Chapman & Hall: London.

[H62] Hass, W. H. 1962. Conodonts. In: Moore, R. C. (ed.) Treatise on Invertebrate Paleontology pt W. Miscellanea: Conodonts, Conoidal Shells of Uncertain Affinities, Worms, Trace Fossils and Problematica pp. W3–W69. Geological Society of America, and University of Kansas Press.

[M62] Müller, K. J. 1962. Supplement to systematics of conodonts. In: Moore, R. C. (ed.) Treatise on Invertebrate Paleontology pt W. Miscellanea: Conodonts, Conoidal Shells of Uncertain Affinities, Worms, Trace Fossils and Problematica pp. W246–W249. Geological Society of America, and University of Kansas Press.

[R79] Ross, C. A. 1979. Carboniferous. In: Robison, R. A., & C. Teichert (eds) Treatise on Invertebrate Paleontology pt A. Introduction. Fossilisation (Taphonomy), Biogeography and Biostratigraphy pp. A254–A290. The Geological Society of America, Inc.: Boulder (Colorado), and The University of Kansas: Lawrence (Kansas).

[S88] Sweet, W. C. 1988. The Conodonta: Morphology, taxonomy, paleoecology, and evolutionary history of a long extinct animal phylum. Clarendon Press: Oxford.

[WM03] Webster, G. D., C. G. Maples, R. Mawson & M. Dastanpour. 2003. A cladid-dominated Early Mississippian crinoid and conodont fauna from Kerman Province, Iran and revision of the glossocrinids and rhenocrinids. Journal of Paleontology 77 (Suppl. 3): 1–35.