Rolfsmeier, Susan , Ferguson, Carolyn .
Exploring diversity and assessing relationships in the North American Lappula (Boraginaceae).
The genus Lappula includes over 60 species of annual and biennial herbs, many associated with dry habitats in parts of Central Asia. In contrast to the Eurasian species, the western North American taxa have been poorly studied. As many as 26 species were described from North America in the late nineteenth and early twentieth centuries, and thirteen native taxa were recognized by I. M. Johnston in his 1924 revisionary work. Taxonomic uncertainty led to a complicated nomenclature, and morphological and ecological variation have continued to pose challenges for species delimitation. Floristic treatments have tended to treat the western North American taxa as synonymous with, or as varieties of, three species in particular: L. redowskii (Hornem.) Greene (a name properly applied more narrowly to Siberian material), L. squarrosa (Retz.) Dumort. (native to Eurasia and widely introduced in North America and elsewhere), and L. texana (Scheele) Britt. (remaining material with cupulate marginal spines on the mericarps). Herbarium and literature study were conducted in order to investigate the potential for hidden diversity among the North American material and to resolve long-standing nomenclatural questions. Molecular characters from nrITS and the chloroplast regions trnS-trnG and rpl32-trnL were used to infer relationships of North American taxa relative to Eurasian diversity. Results of phylogenetic analyses and an updated taxonomy for North America are presented along with discussion of morphological and geographic patterns. Related, ongoing collaboration with a Russian colleague enhances the broader implications of this research.
Log in to add this item to your schedule
1 - Kansas State University, Herbarium and Division of Biology, Manhattan, KS, 66506-4901
Presentation Type: Oral Paper:Papers for Sections
Location: Delaware C/Hyatt
Date: Wednesday, July 11th, 2012
Time: 4:15 PM