Problematoconites perforata, from Heredia (1999). Scale bar equals 100 μm.

Belongs within: Vertebrata.
Contains: Westergaardodina, Proconodontida, Conodonti.

Conodonts were a major group of basal vertebrates from the Late Cambrian to the Triassic, mostly known from small phosphatised elements that are now interpreted as their teeth or tooth-plates (the only mineralised part of the animals). The life arrangement of these elements is commonly known as the apparatus, and often included a number of different element forms (particularly in some derived subgroups). Because the apparatus usually became dissasociated after death, making it difficult to recognise whether or not elements came from a single individual, many authors have classified conodonts using an artificial form-taxonomy that treats individual elements as separate taxa. Examples of such form taxa include the Belodontidae, established to include denticulated, fang-like elements that might have an enlarged base (Hass 1962).

Conodonts are divisible between Paraconodontida and Euconodonta (the latter divided between Proconodontida and Conodonti); in paraconodonts, the elements are simple conical structures that grew from around the base whereas euconodonts have elements divisible into a basal layer and an upper layer that grew by external accretion around the entire structure (Sweet & Donoghue 2001). These differences have been interpreted as indicating that paraconodonts had only the base of the element surrounded by secretory epithelium, whereas euconodont elements would have been retracted into pockets of epithelium and only exposed when the animal was feeding. Soft-body remains are only known for two species of Conodonti, with both being eel- or lamprey-like animals.

<==Conodonta [Conodontiformes, Conodontophorida, Neurodontiformes]
    |--Problematoconites Müller 1959 DJ71 [Paraconodontida SD01]
    |    `--*P. perforata Müller 1959 DJ71
    `--Euconodonta [Belodellida] SD01
         |--Proconodontida SD01
         `--Conodonti SD01

Conodonta incertae sedis:
  Aspelundia fluegeli (Walliser 1964) WBN02
  Muellerodus cambricus Müller 1959 RNP03
  Westergaardodina DJ71
  Prooneotodus RNP03
    |--P. gallatini Müller 1959 RNP03
    `--P. rotundatus LM05
  Protognathus praedelicatus Lane, Sandberg & Ziegler 1980 WM03
  Jumudontus gananda PBJ03
  Kallidontus nodosus PBJ03
  Stiptognathus borealis PBJ03
  Fahraeusodus marathonensis PBJ03
  Stultodontus costatus PBJ03
  Eucharodus parallellus PBJ03
  Neomultoistodus compressus PBJ03
  Mockina slovakensis W03
  Filodontus Pyle, Barnes & Ji 2003 PBJ03
    `--*F. filosus (Ethington & Clark 1964) [=Scolopodus filosus] PBJ03
  Prosagittodontus RNP03
    |--P. eureka Müller 1959 RNP03
    `--P. minimus Müller & Hinz 1991 RNP03
  Colaptoconus PBJ03
    |--C. multiplicatus PBJ03
    `--C. quadraplicatus PBJ03
  *Bipennatus bipennatus (Bischoff & Ziegler 1957) D02
  Playfordia Glenister & Klapper 1966 [Playfordiidae] D02
    `--P. primitiva (Bischoff & Ziegler 1957) D02
  Paragondolella AFZ04
    |--P. inclinata AFZ04
    `--P. polygnathiformis K79
  Budurovignathus mungoensis AFZ04
  Sagittodontus Rhodes 1953 DJ71
    |--*S. robustus Rhodes 1953 DJ71
    |--S. asymmetricus [=Furnishina asymmetrica] DJ71
    `--S. dahlmani Müller 1959 [incl. S. dunderbergiae Müller 1959] DJ71
  Laterlonchodina simplex CB86
  Illinella Rhodes 1952 H62
    `--*I. typica Rhodes 1952 H62
  Lewistownella Scott 1942 H62
    `--*L. agnewi Scott 1942 H62
  Belodontidae [Belodidae] H62
    |--Belodus Pander 1856 H62
    |    `--*B. gracilis Pander 1856 H62
    |--Microcoelodus Branson & Mehl 1933 H62
    |    `--*M. typus Branson & Mehl 1933 H62
    `--Ptiloconus Sweet 1955 [=Pteroconus Branson & Mehl 1933 non Hinde in Fox 1900] H62
         `--*P. gracilis (Branson & Mehl 1933) [=*Pteroconus gracilis] H62
  Cornuramia Smith 1907 H62
    `--*C. monodonta Smith 1907 H62
  Goniodontus Ethington 1959 H62
    `--*G. superbus Ethington 1959 H62
  Lonchodus Pander 1856 [=Centrodus Pander 1856 nec Giebel 1847 nec M’Coy 1848] H62
    `--*L. simplex (Pander 1856) [=*Centrodus simplex] H62
  Ptilognathus Elias 1956 H62
    `--*P. fayi Elias 1956 H62
  Scotlandia Cossmann 1909 [=Valentia Smith 1907 nec Stål 1856 nec Smith 1901] H62
    `--*S. morrochensis (Smith 1907) [=*Valentia morrochensis] H62
  Trapezognathus Lindström 1954 H62
    `--*T. quadrangulum Lindström 1954 H62
  Caenodontus serrulatus RR79
  Pranognathus tenuis (Aldridge 1972) M02
  Leukorhinion ambonodes LM05
  Macerodus dianae LM05
  Lumidens vitreus Ethington et al. 1986 LM05
  Prionognathus ordovicicus LM05
  Cambropustula kinnekullensis LM05
  Scapulidens primus LM05
  Reutterodus andinus S88
  Windsorgnathus windsorensis S88
  Nicoraella S88
    |--N. germanica S88
    `--N. kockeli S88

*Type species of generic name indicated


[AFZ04] Amati, L., R. M. Feldmann & J.-P. Zonneveld. 2004. A new family of Triassic lobsters (Decapoda: Astacidea) from British Columbia and its phylogenetic context. Journal of Paleontology 78 (1): 150–168.

[CB86] Chen D.-Q. & Bao H. 1986. Lower Permian ostracodes from the Chihsia Formation of Jurong and Longtan, Jiangsu Province. Acta Micropalaeontologica Sinica 3 (2): 107–132.

[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.

[D02] Dzik, J. 2002. Emergence and collapse of the Frasnian conodont and ammonoid communities in the Holy Cross Mountains, Poland. Acta Palaeontologica Polonica 47: 565–650.

[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.

[K79] Kummel, B. 1979. Triassic. In: Robison, R. A., & C. Teichert (eds) Treatise on Invertebrate Paleontology pt A. Introduction. Fossilisation (Taphonomy), Biogeography and Biostratigraphy pp. A351–A389. The Geological Society of America, Inc.: Boulder (Colorado), and The University of Kansas: Lawrence (Kansas).

[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.

[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.

[RNP03] Robson, S. P., G. S. Nowlan & B. R. Pratt. 2003. Middle to Upper Cambrian linguliformean brachiopods from the Deadwood Formation of subsurface Alberta and Saskatchewan, Canada. Journal of Paleontology 77 (2): 201–211.

[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.

[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.

[W03] Wellnhofer, P. 2003. A Late Triassic pterosaur from the Northern Calcareous Alps (Tyrol, Austria). In: Buffetaut, E., & J.-M. Mazin (eds) Evolution and Palaeobiology of Pterosaurs. Geological Society Special Publications 217: 5–22. The Geological Society: London.

[WBN02] Won, M.-Z., R. B. Blodgett & V. Nestor. 2002. Llandoverian (Early Silurian) radiolarians from the Road River Formation of east-central Alaska and the new family Haplotaeniatumidae. Journal of Paleontology 76 (6): 941–964.

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