Hostname: page-component-cd9895bd7-gvvz8 Total loading time: 0 Render date: 2024-12-24T18:55:18.405Z Has data issue: false hasContentIssue false
  • English
  • Français

Schopfodus, a new conodont genus from the upper Middle Ordovician of eastern North America

Published online by Cambridge University Press:  20 May 2016

Stephen A. Leslie
Stephen A. Leslie*
Affiliation:
Department of Geological Sciences, The Ohio State University, Columbus 43210
Get access Rights & Permissions [Opens in a new window]

Extract

Apparatus-based conodont taxonomy has organized the plethora of generic and specific names of form-based taxonomy into a more biologically and phylogenetically sound taxonomy (Schopf, 1966; Webers, 1966; Bergström and Sweet, 1966; Sweet and Bergström, 1972; Rhodes and Austin, 1981; Sweet, 1981, 1988). In the transition from form-based to apparatus-based taxonomy, some conodonts that are not very common, or that have only one or two element types in their apparatus, have remained in a state of form-based taxonomy limbo. An example of this is Trichonodella? tricurva (Schopf, 1966). This relatively uncommon species was known from only one element type (Schopf, 1966) and has not been used in biostratigraphy. Schopf (1966) questioned the generic assignment of T.? tricurva and noted its distinct morphology. Sweet and Bergström (1972) indicated that the type species of Trichonodella (Branson and Mehl, 1948) is a junior synonym of Plectodina aculeata, or of a closely related Plectodina species. Trichonodella? tricurva does not fit within the apparatus-based generic concept of Plectodina (Sweet, 1981), and it is therefore inappropriate to refer it to Trichonodella or Plectodina. No genus contains a tertiopedate element that is morphologically similar to the holotype of T.? tricurva (Schopf, 1966). Additional material from strata that are in part coeval with the stratum typicum of T.? tricurva supports the idea that T.? tricurva represents a new genus. The new genus Schopfodus is proposed for the conodont elements described by Schopf as T.? tricurva and the associated elements of its apparatus.

Type
Paleontological Notes
Information
Journal of Paleontology , Volume 70 , Issue 1 , January 1996 , pp. 166 - 168
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

Bassler, R. S. 1925. Classification and stratigraphic use of the conodonts. Geological Society of America Bulletin, 36:218–220.Google Scholar
Bergström, S. M. 1981. Superfamily Prioniodontacea Bassler, 1925, p. W120–W137. In Robison, R. A. (ed.), Treatise on Invertebrate Paleontology, Part W, Supplement 2. Geological Society of America and University of Kansas Press, Lawrence.Google Scholar
Bergström, S. M., and Sweet, W. C. 1966. Conodonts from the Lexington Limestone (Middle Ordovician) of Kentucky and its equivalents in Ohio and Indiana. Bulletins of American Paleontology, 50(229):271–441.Google Scholar
Branson, E. B. 1938. Stratigraphy and paleontology of the Lower Mississippian of Missouri. Part I. University of Missouri Studies 13(3):1–208.Google Scholar
Branson, E. B., and Mehl, M. G. 1933. Conodont studies no. 1: Conodonts from the Harding Sandstone of Colorado; Bainbridge (Silurian) of Missouri; Jefferson City (Lower Ordovician) of Missouri. University of Missouri Studies, 8(1):5–72.Google Scholar
Branson, E. B., and Mehl, M. G. 1948. Conodont homonyms and names to replace them. Journal of Paleontology, 22:527–528.Google Scholar
Dzik, J. 1976. Remarks on the evolution of Ordovician conodonts. Acta Palaeontologica Polonica, 21:395–455.Google Scholar
Hass, W. H. 1959. Conodonts from the Chappel Limestone of Texas. United States Geological Survey Professional Paper, 294J:365–400.Google Scholar
Pander, C. H. 1856. Monographie der fossilen Fische des Silurischen Systems der Russisch-Baltischen Gouvernements. Kaiserlichen Akademie der Wissenschaften St. Petersburg, 91 p.Google Scholar
Lindström, M. 1955. Conodonts from the lowermost Ordovician strata of south-central Sweden. Geologiska Föreningens I Stockholm Förhandlingar, 76:517–604 (1954).Google Scholar
Lindström, M. 1971. Lower Ordovician conodonts of Europe, p. 21–61. In Sweet, W. C. and Bergström, S. M. (eds.), Symposium on conodont biostratigraphy, Geological Society of America Memoir, 127.Google Scholar
Rhodes, F. T. H., and Austin, R. L. 1981. Natural assemblages of elements: interpretation and taxonomy, p. W68–W78. In Robison, R. A. (ed.), Treatise on Invertebrate Paleontology Part W, Supplement 2. Geological Society of America and University of Kansas Press, Lawrence.Google Scholar
Schopf, T. J. 1966. Conodonts of the Trenton Group (Ordovician) in New York, southern Ontario, and Quebec. New York State Museum and Science Service Bulletin, 405, 105 p.Google Scholar
Stauffer, C. R. 1935. The conodont fauna of the Decorah Shale (Ordovician). Journal of Paleontology, 9:596–620.Google Scholar
Sweet, W. C. 1981. Macromorphology of elements and apparatuses, p. W5–W20. In Robison, R. A. (ed.), Treatise on Invertebrate Paleontology Part W, Supplement 2. Geological Society of America and University of Kansas Press, Lawrence.Google Scholar
Sweet, W. C. 1988. The Conodonta: Morphology, taxonomy paleoecology and evolutionary history of a long-extinct animal phylum, Oxford University Press, New York, 169 p.Google Scholar
Sweet, W. C. 1991. Genus Polyplacognathus Stauffer, 1935, p. 159–164. In Ziegler, W. (ed.), Catalogue of Conodonts, E. Schweizerbart'sche Verlagsbuchhandlung 5.Google Scholar
Sweet, W. C., and Bergstr, S. M.öm. 1972. Multielement taxonomy and Ordovician conodonts. Geologica et Palaeontologica, SB-1:29–42.Google Scholar
Webers, G. F. 1966. The Middle and Upper Ordovician conodont faunas of Minnesota. Minnesota Geological Survey Special Publication, 4, 123 p.Google Scholar