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UBC Theses and Dissertations

A taxonomic revision of the genera Antennaria and Symphyotrichum (Asteraceae) in British Columbia, Canada, with additional perspectives on the role of taxonomy within the biological sciences Fenneman, James Daniel Arnold


Antennaria and Symphyotrichum represent two of the most taxonomically complex genera of the family Asteraceae in North America. Extensive hybridization and polyploidy contribute to many of the taxonomic difficulties encountered within both genera, and in Antennaria these are compounded by the presence of widespread apomixis. This suite of factors has contributed to considerable taxonomic uncertainty in these genera, particularly in the Pacific Northwest where they are both diverse and understudied. This study uses a traditional, specimen-based alpha-taxonomic methodology to investigate the taxonomy of these two genera within the western Canadian province of British Columbia. It uses both a detailed review of existing herbarium collections from within the region of interest, as well as a comprehensive review of existing taxonomic and floristic literature pertaining to these genera, to provide a taxonomic framework that is better representative of these genera in British Columbia. This study provides clarification on a number of unresolved taxonomic and floristic uncertainties, including the incorrect application of nomenclature, poorly defined species limits, incomplete or erroneous morphological circumscriptions, incorrect geographic distributions, and inadequate identification criteria. Several taxa that had not previously been recognized formally in the region, both native and exotic, are documented here and provided a full accounting of their occurrence. It also provides the first comprehensive summary of putative hybrids within these genera in the Pacific Northwest. Dichotomous keys for the identification of taxa within these genera in British Columbia were developed that capture new developments that have resulted from this study. Finally, the importance of taxonomy to the biological sciences is elucidated in the context of this study, and perspectives on the Taxonomic Impediment and the relationship between academia and taxonomy are detailed and discussed.

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