Reconstructed apparatus of Idiognathodus, viewed above centre, from Purnell & O’Donoghue (1997).

Belongs within: Spathognathodontidae.

The Idiognathodontidae are a family of conodonts known from the Upper Carboniferous and Permian, characterised by carminiscaphate platform (Pa) elements whose upper surfaces typically bear three longitudinal rows of nodes or denticles. Where the entire apparatus is known, it is seximembrate and includes an alate Sa element with a denticulate posterior process (Sweet 1988).

The earliest known idiognathodontid is Declinognathodus noduliferus in which the Pa elements have the carina curving laterally to join the outer marginal denticle row a short distance behind the end of the blade (Sweet 1988).

<==Idiognathodontidae [Idiognathinae, Idiognathodontinae]
    |--+--Idiognathoides Harris & Hollingsworth 1933S88 [incl. Polygnathodella Harlton 1933H62]
    |  |    |--*I. sinuata Harris & Hollingsworth 1933H62
    |  |    |--I. convexusS88
    |  |    |--I. fossatusS88
    |  |    |--I. macerS88
    |  |    |--I. marginodosusS88
    |  |    |--I. ouachitensisS88
    |  |    |--I. sulcatusS88
    |  |    `--I. tuberculatusS88
    |  `--Neognathodus Dunn 1970S88
    |       |--N. anodosusS88
    |       |--N. atokensisS88
    |       |--N. bassleriS88
    |       |--N. bothropsS88
    |       |--N. colombienseS88
    |       |--N. dilatusS88
    |       |--N. medadultimusS88
    |       |--N. medexultimusS88
    |       |--N. metanodosusS88
    |       |--N. roundyiS88
    |       `--N. symmetricusS88
    `--+--Declinognathodus Dunn 1966S88
       |    |--D. lateralisS88
       |    `--D. noduliferus (Ellison & Graves 1941)HM04
       `--+--Streptognathodus Stauffer & Plummer 1932S88
          |    |--*S. excelsus Stauffer & Plummer 1932H62
          |    |--S. alekseeviS88
          |    |--S. barskoviS88
          |    |--S. bellus Chernyk & Ritter 1997CL02
          |    |--S. cancellosusS88
          |    |--S. eccentricusS88
          |    |--S. elegantulusS88
          |    |--S. elongatus Gunnell 1933AS93
          |    |--S. expansusS88
          |    |--S. gracilisS88
          |    |--S. oppletusS88
          |    |--S. ruzhenceviS88
          |    |--S. simulatorS88
          |    |--S. suberectusS88
          |    `--S. wabaunsensisS88
          `--Idiognathodus Gunnell 1931S88 (see below for synonymy)
               |--*I. claviformis Gunnell 1931H62
               |--I. arendtiS88
               |--I. bachmatricusS88
               |--I. claviformisS88
               |--I. delicatusS88
               |--I. ellisoniRR79
               |--I. humerusT85
               |--I. klapperiS88
               |--I. lobulatusS88
               |--I. magnificusS88
               |--I. obliquusS88
               |--I. robustusS88
               |--I. sagittalisS88
               |--I. sinuosusS88
               |--I. tersusS88
               |--I. toretzianusS88
               |--I. trigonolobatusS88
               `--*Scottella’ typica Rhodes 1952 [=*Scottognathus typica]H62

Idiognathodus Gunnell 1931S88 [incl. Scottella Rhodes 1952 non Enderlein 1910H62, Scottognathus Rhodes 1953SD01, H62]

*Type species of generic name indicated


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

[CL02] Caridroit, M., A. Lamerandt, J.-M. Dégardin, A. F. de Dios & D. Vachard. 2002. Discovery of radiolaria and conodonts in the Carboniferous–Permian of San Salvador (Puebla, Mexico); biostratigraphic implications. Comptes Rendus Palevol 1: 205–211.

[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.

[HM04] Hoare, R. D., & G. K. Merrill. 2004. A Pennsylvanian (Morrowan) ostracode fauna from Texas. Journal of Paleontology 78 (1): 185–204.

[RR79] Ross, C. A., & J. R. P. Ross. 1979. Permian. In: Robison, R. A., & C. Teichert (eds) Treatise on Invertebrate Paleontology pt A. Introduction. Fossilisation (Taphonomy), Biogeography and Biostratigraphy pp. A291–A350. 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.

[SD01] Sweet, W. C., & P. C. J. Donoghue. 2001. Conodonts: past, present, future. Journal of Paleontology 75 (6): 1174–1184.

[T85] Thayer, D. W. 1985. New Pennsylvanian lepospondyl amphibians from the Swisshelm Mountains, Arizona. Journal of Paleontology 59 (3): 684–700.

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