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Probable microvertebrates, vertebrate-like fossils, and weird things from the Wisconsin Ordovician

Published online by Cambridge University Press:  20 May 2016

David L. Clark ,
John K. Sorenson ,
Andrea N. Ladd  and
James R. Freiheit
David L. Clark
Affiliation:
Department of Geology and Geophysics, University of Wisconsin, Madison 53706,
John K. Sorenson
Affiliation:
Department of Geology and Geophysics, University of Wisconsin, Madison 53706,
Andrea N. Ladd
Affiliation:
Department of Geology and Geophysics, University of Wisconsin, Madison 53706,
James R. Freiheit
Affiliation:
Department of Geology and Geophysics, University of Wisconsin, Madison 53706,
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Abstract

Phosphatic microfossils including probable microvertebrates occur in the Early and Middle Ordovician rocks of Wisconsin. The eight types described here include the probable ostracoderm Anatolepis, and six unidentified but possible vertebrate fragments as well as the palaeoscolecid worm Milaculum. These fossils are rare, but at two localities several specimens per kg were recovered over significant stratigraphic intervals. The high concentration of certain fossils in the lower part of the Galena Group suggests that there is stratigraphic value in their description. Identification of similar material or of articulated assemblages of these fossils may eventually lead to identification of biologic affinities.

Type
Research Article
Information
Journal of Paleontology , Volume 73 , Issue 6 , November 1999 , pp. 1201 - 1209
Copyright
Copyright © The Paleontological Society 

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