Hostname: page-component-cd9895bd7-gbm5v Total loading time: 0 Render date: 2024-12-26T04:56:36.208Z Has data issue: false hasContentIssue false

Internal structure of Cambrian Conodonts

Published online by Cambridge University Press:  20 May 2016

K. J. Müller
Affiliation:
Paläontologisches Institut der Universität Bonn, Nussallee 8, D-53115 Bonn
I. Hinz-Schallreuter
Affiliation:
Naturhistorisches Forschungsinstitut, Museum für Naturkunde, Institut für Paläontologie, Invalidenstraße 43, D-10115 Berlin

Abstract

Based on material of the Upper Cambrian of Sweden the internal structure of proto-, para- and euconodonts has been investigated. The protoconodontids Gapparodus and Gumella show some special development of the median unit of the skeletal tissue. In Gapparodus, long, parallel-running lamellae suggest a continuous growth, even of previously secreted lamellae, until their eventual outcropping. In Gumella the fibrous median layer decreases considerably during growth until its complete reduction, which coincides with the disappearance of the posterior wall. Paraconodonts also produced several specialities in their mode of growth. Elements with lateral processes such as Proacodus and Serratocambria developed by allometric growth. The lamellae are much more widely spaced in the process than in the main cusp to attain the required length of the former. In Serratocambria additional lamellae are inserted in the process. Thin sections of tricuspidate westergaardodinids reveal paraconodontid growth with lamellar remains in the tip of the median denticle, which are isolated from the growth lines in the lateral denticles. Based on this observation a hypothetical growth model explains the lamellar development as a result of stress and strain. The Ordovician euconodontid Chosonodina clearly shows white matter and is thus unrelated, but homeomorphic to Westergaardodina. Cambropustula from the lower Upper Cambrian is the oldest euconodont yet but it lacks white matter. The latter was an evolutionary novelty, which progressively developed in the euconodont line.

The systematic position of conodonts is briefly discussed; the studied material cannot contribute to the hypothesis of neural crest derived skeletal tissue.

Type
Research Article
Copyright
Copyright © The Paleontological Society 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Abaimova, G. P. 1978. Pozdnekembrijskie konodonti zentral'noga Kazkhstana. (Late Cambrian conodonts of central Kazakhstan) Paleontologicheskij Zhurnal, 1978:7787.Google Scholar
Aldridge, R. J., Briggs, D. E. G., Clarkson, E. N. K., and Smith, M. P. 1986. The affinities of conodonts—new evidence from the Carboniferous of Edinburgh, Scotland. Lethaia, 19:279291.Google Scholar
Aldridge, R. J., Briggs, D. E. G., Clarkson, E. N. K., and Smith, M. P., Smith, M. P., Clarkson, E. N. K., and Clark, N. D. L. 1993. The anatomy of conodonts. Philosophical Transactions of the Royal Society of London, Series B, 340:405421.Google Scholar
Aldridge, R. J., Briggs, D. E. G., Clarkson, E. N. K., and Theron, J. N. 1993. Conodonts with preserved soft tissue from a new Ordovician Konservat-Lagerstätte. Journal of Micropalaeontology, 12:113117.Google Scholar
Taixiang, An, Fangf, Zhang, Weida, Xiang, Yougin, Zhang, Wenhao, Xu, Huijuan, Zhang, Debiao, Jiang, Changsheng, Yang, Liandi, Lin, Zhantang, Cui, and Xinchang, Yang. 1983. The conodonts of north China and the adjacent regions. Science Press, Beijing, 223 p. (in Chinese)Google Scholar
Andres, D. 1988. Struktur, apparate und phylogenie primitiver conodonten. Palaeontographica A, 200(4-6), 105.Google Scholar
Barnes, C. R., Rexroad, C. B., and Miller, J. F. 1973. Lower Paleozoic conodont provincialism. Geological Society of America Special Paper, 141:157190.Google Scholar
Barnes, C. R., Rexroad, C. B., and Miller, J. F., Sass, D. B., and Poplawski, M. L. S. 1973. Conodont ulstrastructure: the family Panderodontidae. Life Science Contributions of the Royal Ontario Museum, 90, 36 p.Google Scholar
Bengtson, S. 1976. The structure of some Middle Cambrian conodonts, and the early evolution of conodont structure and function. Lethaia, 9:185206.Google Scholar
Bengtson, S. 1983. The early history of the Conodonta. Fossils and Strata, 15:519.CrossRefGoogle Scholar
Branson, E. B., and Mehl, M. G. 1944. Conodonts, p. 235246. In Shimer, H.W. and Shrock, R.R. (eds.), Index Fossils Oof North America. John Wiley and Sons, New York.Google Scholar
Briggs, D. E. G., Clarkson, E. N. K., and Aldridge, R. J. 1983. The conodont animal. Lethaia, 16:114.CrossRefGoogle Scholar
Briggs, D. E. G., Clarkson, E. N. K., and Aldridge, R. J., Aldridge, R. J., and Smith, M. P. 1987. Conodonts are not aplacophoran molluscs. Lethaia, 20:381382.Google Scholar
Min-Juan, Chen, Jian-Hua, Zhang, and Qing, Yu. 1986. Cambrian-Ordovician conodonts from the Jiangnan region. Acta Micropalaeontologica Sinica, 3:361372.Google Scholar
Dzik, J. 1986. Chordate affinities of the conodonts, p. 241254. In Hoffman, A. and Nitecki, M.H. (eds.), Problematic Fossil Taxa. Oxford University Press, New York, Clarendon Press, Oxford.Google Scholar
Hinz, I. 1992. Oberkambrische Conodonten aus Schweden. Archiv für Geschiebekunde 1:241270.Google Scholar
Jeppson, L. 1979. Conodont element function, Lethaia, 12:153171.Google Scholar
Kemp, A., and Nicoll, R. 1993. A histochemical analysis of biological residues in conodont elements. International Geological Correlation Programme 328 Palaeozoic Microvertebrates-SDS: Gross Symposium Abstracts, Göttingen.Google Scholar
Kemp, A., and Nicoll, R. 1995. Protochordate affinities of conodonts. Courier Forschungsinstitut Senckenberg, 182:235245.Google Scholar
Kemp, A., and Nicoll, R. 1996. Defining the hard tissue histology of euconodont elements. Sixth North American Paleontological Convention, Abstracts of Papers, Special Publication 8:205, Washington.CrossRefGoogle Scholar
Krejsa, R. J., Bringas, P. Jr., and Slavkin, H. C. 1990a. The cyclostome Model: an interpretation of conodont element structure and function based on cyclostome tooth morphology, function and life history. Courier Forschungsinstitut Senckenberg, 118:473492.Google Scholar
Krejsa, R. J., Bringas, P. Jr., and Slavkin, H. C. 1990b. A neontological interpretation of conodont elements based on agnathan cyclostome tooth structure, function, and development. Lethaia, 23:359378.CrossRefGoogle Scholar
Landing, E. 1977. “Prooneotodus” tenuis (Müller, 1959) apparatuses from the Taconic allochthon, eastern New York. Journal of Paleontology, 51:1073.Google Scholar
Lindström, M. 1970. A suprageneric taxonomy of the conodonts. Lethaia, 3:427445.Google Scholar
Miller, J. F. 1969. Conodont fauna of the Notch Peak Limestone (Cambro-Ordovician), House Range, Utah. Journal of Paleontology, 43:413439.Google Scholar
Miller, J. F. 1976. An evolutionary transition between paracondonts and conodontophorids from the Wilberns Formation (Upper Franconian) of Central Texas. Geological Society of America, Abstracts with Programs, 8:498.Google Scholar
Miller, J. F. 1980. Taxonomic revisions of some Upper Cambrian and Lower Ordovician conodonts with comments on their evolution. University of Kansas Paleontological Contributions Paper, 99, 30 p.Google Scholar
Miller, J. F. 1981. Systematic descriptions, p. W111W115. In Robison, R. A. (ed.), Treatise on Invertebrate Paleontology, Part W, Miscellanea, Supplement 2. Geological Society of America and University of Kansas Press, Lawrence.Google Scholar
Miller, J. F. 1984. Cambrian and earliest Ordovician conodont evolution, biofacies and provincialism. Geological Society of America Special Paper, 196:4368.Google Scholar
Missarzhevsky, V. V. 1973. Konodontoobraznye organizmy iz ptranichnykh sloev kembriya i deoekembriya Sibirkoj platformy i Kazakhstana. Trudy Instituti Geologii i Geofiziki Sibirskoe Otdelnie, 49:5357.Google Scholar
Müller, K. J. 1959. Kambrische Conodonten. Zeitschrift der Deutschen Geologischen Gesellschaft, 111:434485.CrossRefGoogle Scholar
Müller, K. J. 1962. Supplements to systematics of conodonts, p. W246W249. In Moore, R.C. (ed.), Treatise on Invertebrate Paleontology, Part W, Miscellanea. Geological Society of America and University of Kansas Press, Lawrence.Google Scholar
Müller, K. J. 1964. Conodonten aus dem unteren Ordovizium von Südkorea. Neues Jahrbuch für Geologie und Paläontologie, Abhandlungen, 119:93102.Google Scholar
Müller, K. J. 1981. Internal structure, p. W20W41. In Robison, R.A. (ed.), Paleontology, Part W, Miscellanea. Geological Society of America and University of Kansas Press, Lawrence.Google Scholar
Müller, K. J., and Nogami, Y. 1971. über den Feinbau der Conodonten. Memoirs of the Faculty of Science, Kyoto University, Series of Geology and Mineralogy, 38:187.Google Scholar
Müller, K. J., and Nogami, Y. 1972a. Growth and function of conodonts. Abstracts 24th International Geological Congress, Montreal, Section 7:2027.Google Scholar
Müller, K. J., and Nogami, Y. 1972b. Entöken und Bohrspuren bei den Conodontophorida. Paläontologische Zeitschrift, 46:6896.CrossRefGoogle Scholar
Müller, K. J., and Nogami., Y., and Hinz, I. 1991. Upper Cambrian conodonts from Sweden. Fossils and Strata, 28, 153 p.Google Scholar
Pander, C. H. 1856. Monographie der fossilen Fische des silurischen Systems der russisch- baltischen Gouvernements. Akademie der Wissenschaften St. Petersburg, 191.Google Scholar
Pierce, R. W. and Langenheim, R. L. 1970. Surface patterns on selected Mississippian conodonts. Geological Society of America, Bulletin 81:32253236.CrossRefGoogle Scholar
Purnell, M. A. 1995. Microwear on conodont elements and macrophagy in the first vertebrates. Nature, 374:798800.Google Scholar
Purnell, M. A., and von Bitter, P. H. 1992. Blade-shaped conodont elements functioned as cutting teeth. Nature, 359:629631.Google Scholar
Rohon, J. V., and von Zittel, K. A. 1887. über Conodonten. Sitzungsbericht der Mathematisch Naturwissenschaftlichen Klasse der Bayerischen Akademie der Wissenschaften München, 16:108136.Google Scholar
Sansom, I. J., Smith, M. P., Armstrong, H. A., and Smith, M. M. 1992. Presence of the earliest vertebrate hard tissues in conodonts. Science, 256:13081311.Google Scholar
Sansom, I. J., Smith, M. P., Armstrong, H. A., and Smith, M. M., and Smith, M. M. 1994. Dentine in conodonts. Nature, 368:591.CrossRefGoogle Scholar
Sansom, I. J., Smith, M. P., Armstrong, H. A., Smith, M. P., and Smith, M. M. 1996. The histology of Cambro-Ordovician Vvertebrates. Sixth North American Paleontological Convention, Abstracts of Papers, Special Publication 8:339, Washington.Google Scholar
Sweet, W. C. 1988. The Conodonta: Morphology, Taxonomy, Paleoecology, and Evolutionary History of a Long-Extinct Animal Phylum. Clarendon Press, Oxford, 212 p.Google Scholar
Szaniawski, H. 1980. Conodonts from the Tremadocian chalcedony beds, Holy Cross Mountains, Poland. Acta Palaeontologica Polonica, 25:101121.Google Scholar
Szaniawski, H. 1982. Chaetognath grasping spines recognized among Cambrian protoconodonts. Journal of Paleontology, 56:806810.Google Scholar
Szaniawski, H. 1983. Structure of protoconodont elements. Fossils and Strata, 15:2127.Google Scholar
Szaniawski, H. 1987. Preliminary structural comparison of protoconodont and euconodont elements, p. 3547. In ALDRIDGE, R.J. (ed.), Paleobiology of Conodonts. Ellis Horwood, Chichester.Google Scholar
Szaniawski, H., and Bengtson, S. 1988. Formation of the first euconodont elements. Courier Forschungsinstitut Senckenberg, 102:256257.Google Scholar
Szaniawski, H., and Bengtson, S. 1993. Origin of euconodont elements. Journal of Paleontology, 67:640654.Google Scholar
Tillier, S., and Cuif, J.-P. 1986. Léanimal-conodonte est-il un Mollusque Aplacophore? Compte Rendu Académie des Sciènces, Paris, 303, 11:627632.Google Scholar
Tipnis, R. S., and Chatterton, B. D. E. 1979. An occurrence of the apparatus Of “Prooneotodus” (Conodontophorida) from the Road River Formation, Northwest Territories. Current Research, Part B, Geological Survey of Canada Paper 79-1B:259262.Google Scholar
von Bitter, P., David, K., and Ferris, G. 1996. Fossil bacteria on faecal conodont assemblages from the Upper Carboniferous of England, Scotland, and the United States. Sixth International Conodont Symposium (ECOS VI), Abstracts:62. Warszawa.Google Scholar