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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
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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 

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