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The trilobite genus Placoparia from the Ordovician of the Valongo area, North Portugal

Published online by Cambridge University Press:  01 May 2009

M. Romano
Affiliation:
Department of Geology, University of Sheffield, Mappin Street, Sheffield, S1 3JD

Summary

The three species of Placoparia; P. (Placoparia) cambriensis Hicks, P. (Coplacoparia) tournemini (Rouault) and P. (Coplacoparia) borni Hammann have been recognized from the Ordovician of North Portugal. New subspecies of P. (Placoparia) cambriensis have been established on the basis of differences in the pygidium and suggests the presence of two, broadly coeval, populations in western Europe during the Llanvirn. Quantitative analyses have provided information on growth patterns.

Type
Articles
Copyright
Copyright © Cambridge University Press 1976

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