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Morphometric patterns in Middle Triassic Neogondolella mombergensis (Conodonta), Fossil Hill, Nevada

Published online by Cambridge University Press:  19 May 2016

Scott M. Ritter*
Affiliation:
School of Geology, Oklahoma State University, Stillwater 74078

Abstract

The Fossil Hill Member of the Prida Formation (Fossil Hill, Nevada) yields one of the most continuous records of Middle Triassic conodont evolution currently known. Because of different taxonomic viewpoints, this record has been alternately interpreted to represent either morphological stasis or gradual, biostratigraphically significant morphogenesis. Univariate and multivariate morphometric analysis of 18 successive Neogondolella Pa element populations suggests that the majority of specimens at Fossil Hill (including N. constricta emend. sensu Nicora and Kovacs, 1984) belong to a single, morphologically diverse species, Neogondolella mombergensis (Tatge). Time series of individual character means from 18 stratigraphic horizons in the Fossil Hill display nondirectional morphologic trends for which a random walk model cannot be rejected. Time series of transformed multivariate means constitute biologs that may prove useful in regional correlation.

Type
Research Article
Copyright
Copyright © The Paleontological Society 

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