Conodonta

Apparatus elements of Colaptoconus, from the United States Geological Survey.

Belongs within: Craniata.
Contains: Furnishidae, 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had only the base of the element surrounded by secretory epithelium, whereas euconodont elements would have been retracted into pockets of epithelium and only exposed when the animal was feeding.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 few species of Conodonti, with known examples being eel- or lamprey-like animals.

Fomitchella is a genus of conical fossils known from the Early Cambrian that has been associated by some authors with conodonts (Durham 1978).

The Belodontidae is a form-group of conodonts known from the Ordovician and Silurian periods (with potential representatives in the Devonian) in which the pulp cavity is surmounted by a single, straight or curved, denticulated fang-like cusp whose base may be greatly enlarged (Hass 1962).

<==Conodonta [Conodontiformes, Conodontophorida, Neurodontiformes]
    |--Paraconodontida [Furnishinacea]SD01
    |    |--FurnishidaeW93
    |    `--WestergaardodinaW93
    `--Euconodonta [Belodellida]SD01
         |--ProconodontidaSD01
         `--ConodontiSD01
Conodonta incertae sedis:
  Muellerodus cambricus Müller 1959RNP03
  ProoneotodusRNP03
    |--P. gallatini Müller 1959RNP03
    `--P. rotundatusLM05
  Protognathus praedelicatus Lane, Sandberg & Ziegler 1980WM03
  Jumudontus Cooper 1981AS93
    `--J. ganandaPBJ03
  Kallidontus nodosusPBJ03
  Stiptognathus borealisPBJ03
  Stultodontus costatusPBJ03
  Neomultoistodus compressusPBJ03
  Filodontus Pyle, Barnes & Ji 2003PBJ03
    `--*F. filosus (Ethington & Clark 1964) [=Scolopodus filosus]PBJ03
  ColaptoconusPBJ03
    |--C. bolitesAB04
    |--C. floweriAB04
    |--C. multiplicatusPBJ03
    `--C. quadraplicatusPBJ03
  *Bipennatus bipennatus (Bischoff & Ziegler 1957)D02
  Playfordia Glenister & Klapper 1966 [Playfordiidae]D02
    `--P. primitiva (Bischoff & Ziegler 1957)D02
  ParagondolellaAFZ04
    |--P. inclinataAFZ04
    `--P. polygnathiformisK79
  Budurovignathus mungoensisAFZ04
  Sagittodontus Rhodes 1953DJ71
    |--*S. robustus Rhodes 1953DJ71
    |--S. asymmetricus [=Furnishina asymmetrica]DJ71
    `--S. dahlmani Müller 1959 [incl. S. dunderbergiae Müller 1959]DJ71
  Laterlonchodina simplexCB86
  Illinella Rhodes 1952H62
    `--*I. typica Rhodes 1952H62
  Lewistownella Scott 1942H62
    `--*L. agnewi Scott 1942H62
  Belodontidae [Belodidae]H62
    |--Belodus Pander 1856H62
    |    `--*B. gracilis Pander 1856H62
    |--Microcoelodus Branson & Mehl 1933H62
    |    `--*M. typus Branson & Mehl 1933H62
    `--Ptiloconus Sweet 1955 [=Pteroconus Branson & Mehl 1933 non Hinde in Fox 1900]H62
         `--*P. gracilis (Branson & Mehl 1933) [=*Pteroconus gracilis]H62
  Cornuramia Smith 1907H62
    `--*C. monodonta Smith 1907H62
  Goniodontus Ethington 1959H62
    `--*G. superbus Ethington 1959H62
  Lonchodus Pander 1856 [=Centrodus Pander 1856 nec Giebel 1847 nec M’Coy 1848]H62
    `--*L. simplex (Pander 1856) [=*Centrodus simplex]H62
  Ptilognathus Elias 1956H62
    `--*P. fayi Elias 1956H62
  Scotlandia Cossmann 1909 [=Valentia Smith 1907 nec Stål 1856 nec Smith 1901]H62
    `--*S. morrochensis (Smith 1907) [=*Valentia morrochensis]H62
  Trapezognathus Lindström 1954H62
    |--*T. quadrangulum Lindström 1954H62
    `--T. diprionAB04
  Caenodontus Behnken 1975AS93
    `--C. serrulatus Behnken 1975AS93
  Leukorhinion ambonodesLM05
  Lumidens vitreus Ethington et al. 1986LM05
  Prionognathus ordovicicusLM05
  Cambropustula Müller & Hinz 1990AS93
    `--C. kinnekullensis Müller & Hinz 1990AS93
  Scapulidens primusLM05
  Reutterodus andinusS88
  Windsorgnathus windsorensisS88
  PyrsognathusMS12
    |--P. latusMS12
    `--P. obliquusMS12
  Pseudobelodella siluricaMS12
  Nudibelodina sensitivaMS12
  Silurognathus maximusJT12
  Aldridgeodus minimusJT12
  Cristodus Repetski 1982AS93
  Dischidognathus Ethington & Clark 1982AS93
    `--D. primus Ethington & Clark 1982AS93
  Fungulodus Gagiev 1979 [incl. Mitrellataxis Chauff & Price 1980]AS93
    `--F. coronella (Chauff & Price 1980)AS93
  Eocarniodus Orchard 1980AS93
    `--E. gracilis (Rhodes 1955)AS93
  Lenodus variabilisAB04
  Yangtzeplacognathus crassusAB04
  Polycostatus oneotensisAB04
  Spinodus spinatusAB04
  Taoqupognathus blandusNW04
  Fomitchella Missarzhevsky 1969D78
    |--F. acinaciformis Missarzhevsky 1969WS93
    `--F. infundibuliformis Missarzhevsky 1969WS93

*Type species of generic name indicated

References

[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.

[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.

[D78] Durham, J. W. 1978. The probable metazoan biota of the Precambrian as indicated by the subsequent record. Ann. Rev. Earth Planet Sci. 6: 21–42.

[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.

[JT12] Jeppsson, L., J. A. Talent, R. Mawson, A. Andrew, C. Corradini, A. J. Simpson, J. Wigforss-Lange & H. P. Schönlaub. 2012. Late Ludfordian correlations and the Lau Event. In: Talent, J. A. (ed.) Earth and Life: Global biodiversity, extinction intervals and biogeographic perturbations through time pp. 653–675. Springer.

[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.

[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.

[NW04] Nitecki, M. H., B. D. Webby, N. Spjeldnaes & Zhen Y.-Y. 2004. Receptaculitids and algae. In: Webby, B. D., F. Paris, M. L. Droser & I. G. Percival (eds) The Great Ordovician Biodiversification Event pp. 336–347. Columbia University Press.

[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.

[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.

[W93] Wills, M. A. 1993. Miscellania. In: Benton, M. J. (ed.) The Fossil Record 2 pp. 555–560. Chapman & Hall: London.

[WS93] Wills, M. A., & J. J. Sepkoski Jr. 1993. Problematica. In: Benton, M. J. (ed.) The Fossil Record 2 pp. 543–554. Chapman & Hall: London.

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