XVI International Botanical Congess

The Artemisia ludoviciana-complex is a widely distributed group of herbaceous perennials in western North America from the Aleutians to Jalisco in central Mexico, which includes approximately 18 taxa. Relationships within the group are confused due to continuous variation within the complex, perhaps as a result of hybridization and polyploidy. The external transcribed spacer (ETS) of 18S-26S rDNA was sequenced from representatives of 8 taxa. A phylogeny emphasizing the diploid taxa was produced from the ETS sequences with Artemisia vulgaris L. as the outgroup. This phylogeny will be used with a morphological character based phylogeny and analysis of the polyploid taxa to resolve relationships within the complex and the evolution of polyploidy.