The outline of the platform in Pa elements of conodont genera such as Palmatolepis is commonly one of the most heavily weighted taxonomic characters. But a taxonomy based only on visual discrimination of Pa elements of Frasnian species of Palmatolepis has resulted in widespread misidentification. Although their Pa elements can be confused, Palmatolepis subrecta, Palmatolepis hassi, and related species from the Frasnian of the Montagne Noire and Iowa can be separated consistently by use of features displayed by other elements of the apparatus, especially the Pb and M elements. To determine if significant differences exist among the Pa elements of these multielement species, digitized outlines of the Pa elements were analyzed using an orientation function similar to the tangent-angle function of F. L. Bookstein. A multielement classification based on the Pb and M elements was tested by a discriminant analysis of the outlines of the Pa elements. The results show that there is close agreement between the two procedures and that systematic differences exist among the Pa elements of groupings based on the Pb and M elements. Unquestionably, quantification of the outlines of platform conodonts will substantially improve taxonomic methods, with consequent enhancement of biostratigraphy.

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