Oneotodus simplex, from Ethington & Brand (1981).

Belongs within: Conodonta.
Contains: Prioniodontida, Clavohamulidae, Drepanoistodontidae, Acanthodontidae, Panderodontida, Scolopodus.

The Conodonti are a major group of conodonts including those lineages derived from the Upper Cambrian to Lower Ordovician genus Teridontus, comprising the majority of familiar conodont species (Sweet & Donoghue 2001). Early Conodonti of the families Oneotodontidae and Protopanderodontidae typically had apparatuses composed of albid, non-geniculate coniform elements with finely striated surfaces (Sweet 1988).

Oneotodus is a genus of very early conodonts from the Lower Ordovician. The original life apparatus of Oneotodus has not been fully established, but would have been composed of an undetermined number of simple single-pointed elements differing in curvature and cross-section. Druce & Jones (1971) derived a number of other early conodont genera from Oneotodus; however, most of the species they assigned to Oneotodus were excluded by Ethington & Brand (1981).

<==Conodonti [Juanognathinae, Protopanderodontida]SD01
    |  i. s.: CornuodontidaeAS93
    |           |--Cornuodus Fahråeus 1966AS93
    |           |    `--C. longibasis (Lindström 1955) [=Protopanderodus longibasis]AS93
    |           |--Scalpellodus Dzik 1976AS93
    |           |    `--S. cavus (Webers 1966)AS93
    |           `--Macerodus Fåhraeus & Nowlan 1978AS93
    |               `--M. dianaeLM05
    |         Strachanognathus Rhodes 1955S88 [StrachanognathidaeAS93]
    |           `--*S. parvus Rhodes 1955H62
    |  `--+--ClavohamulidaeSD01
    |     `--+--DrepanoistodontidaeSD01
    |        `--+--AcanthodontidaeSD01
    |           `--PanderodontidaSD01
       |    |--Teridontus Miller 1980SD01, S88 [Teridontidae]
       |    |    `--T. nakamurai (Nogami 1967)AS93
       |    |--Monocostodus Miller 1980AS93, S88
       |    |    `--M. sevierensisLM05
       |    |--Utahconus Miller 1980AS93, S88
       |    |    `--U. utahensisLM05
       |    `--Oneotodus Lindström 1955S88
       |         |  i. s.: *O. simplex (Furnish 1938) [=Distacodus simplex]DJ71
       |         |         O. circularis Mound 1968WSQ86
       |         |         O. costatus Ethington & Brand 1981AS93
       |         |         O. tenuis Müller 1959DJ71
       |         |--O. gallatini Müller 1959DJ71
       |         |--O. terashimai Nogami 1967DJ71
       |         `--+--O. nakamurai Nogami 1967DJ71
       |            `--+--O. erectus Druce & Jones 1971DJ71
       |               |--O. gracilis (Furnish 1938) [=Distacodus gracilis]DJ71
       |               |--O. variabilis Lindström 1954DJ71
       |               `--+--O. bicuspidatus Druce & Jones 1971DJ71
       |                  |--O. datsonensis Druce & Jones 1971DJ71
       |                  `--Strigaconus Druce & Jones 1971DJ71
       |                       `--*S. simplex Druce & Jones 1971 [incl. Hirsutodontus hirsutus]DJ71
            |  i. s.: Pseudooneotodus Drygant 1974S88
            |           |--*P. beckmanni (Bischoff & Sanneman 1958) [=Oneotodus beckmanni]SS05
            |           |--P. bicornisM02
            |           |--P. boreensisMS12
            |           |--P. mitratus (Moskalenko 1973)AS93
            |           |--P. panuarensisMS12
            |           `--P. tricornisMS12
            |         Tropodus Kennedy 1980S88
            |           |--*T. comptusS88
            |           |--T. australisPBJ03
            |           `--T. sweetiPBJ03
            |         Parutahconus Landing in Fortey et al. 1982S88
            |         Anodontus Stouge & Bagnoli 1988AS93
            |         Juanognathus Serpagli 1974AS93 [incl. Aurilobodus An 1983S88]
            |           |--P. jaanussoniS88
            |           `--J. variabilisPBJ03
            |         Parapanderodus Stouge 1984AS93
            |           |--P. asymmetricus (Barnes & Poplawski 1973) (see below for synonymy)S88
            |           `--P. striatusPBJ03 [=Drepanodus striatusS88; incl. Scolopodus gracilis Ethington & Clark 1964S88]
            |         Ulrichodina Furnish 1938AS93
            |           `--*U. prima Furnish 1938H62
            |--Glyptoconus Kennedy 1980S88
            |    `--G. quadriplicatus (Branson & Mehl 1933)S88
            |--Variabiloconus Landing, Barnes & Stevens 1986S88
            |    |--*V. bassleri (Furnish 1938)S88
            |    `--V. transiapeticusAB04
            `--+--+--Scabbardella Orchard 1980S88
               |  |--Staufferella Sweet, Thompson & Satterfield 1975S88
               |  |    `--S. inaligerae McCracken & Barnes 1981AS93
               |  `--Semiacontiodus Miller 1969S88
               |       |--S. cornuformisS88
               |       |--S. lavadamensisLM05
               |       `--S. nogamii Miller 1969AS93
               `--Protopanderodus Lindström 1971S88
                    |--P. elongatusPBJ03
                    |--P. gradatusPBJ03
                    |--P. insculptusS88
                    |--P. leonardiiPBJ03
                    |--P. liripipusS88
                    |--P. rectusPBJ03
                    `--P. varicostatusS88

Parapanderodus asymmetricus (Barnes & Poplawski 1973) [=Protopanderodus asymmetricus, Juanognathus asymmetricus, Semiacontiodus asymmetricus]S88

*Type species of generic name indicated


[AB04] Albanesi, G. L., & S. M. Bergström. 2004. Conodonts: Lower to Middle Ordovician record. In: Webby, B. D., F. Paris, M. L. Droser & I. G. Percival (eds) The Great Ordovician Biodiversification Event pp. 312–326. Columbia University Press.

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

[DJ71] Druce, E. C., & P. J. Jones. 1971. Cambro-Ordovician conodonts from the Burke River Structural Belt, Queensland. Commonwealth of Australia, Bureau of National Development, Bureau of Mineral Resources, Geology and Geophysics, Bulletin 110: 1–159.

Ethington, R. L., & U. Brand. 1981. Oneotodus simplex (Furnish) and the genus Oneotodus (Conodonta). Journal of Paleontology 55 (1): 239–247.

[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.

[LM05] Lehnert, O., J. F. Miller, S. A. Leslie, J. E. Repetski & R. L. Ethington. 2005. Cambro-Ordovician sea-level fluctuations and sequence boundaries: the missing record and the evolution of new taxa. Special Papers in Palaeontology 73: 117–134.

[M02] Männik, P. 2002. Conodonts in the Silurian of Severnaya Zemlya and Sedov archipelagos (Russia), with special reference to the genus Ozarkodina Branson & Mehl, 1933. Geodiversitas 24 (1): 77–97.

[MS12] Molloy, P. D., & A. J. Simpson. 2012. An analysis of the Ireviken Event in the Boree Creek Formation, New South Wales, Australia. In: Talent, J. A. (ed.) Earth and Life: Global biodiversity, extinction intervals and biogeographic perturbations through time pp. 615–630. Springer.

[PBJ03] Pyle, L. J., C. R. Barnes & Z. Ji. 2003. Conodont fauna and biostratigraphy of the Outram, Skoki, and Owen Creek Formations (Lower to Middle Ordovician), Wilcox Pass, Alberta, Canada. Journal of Paleontology 77 (5): 958–976.

[SS05] Sansom, I. J., & M. P. Smith. 2005. Late Ordovician vertebrates from the Bighorn Mountains of Wyoming, USA. Palaeontology 48 (1): 31–48.

[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.

[WSQ86] Wang C.-Y., Shi C.-G. & Qu G.-S. 1986. Conodonts and ostracodes from the Devonian “Heitai Formation” of Mishan County, Heilongjiang Province. Acta Micropalaeontologica Sinica 3 (2): 205–214.

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