Abstract Detail

Systematics Section/ASPT

Kephart, Susan [1], Theiss, Kathryn E [1], Culley, Theresa [2], Archibald, Jenny [3], Cartieri, Francis [2].

Solving taxonomic puzzles: Insights on delimiting western species of Camassia (Asparagaceae: Agavoideae).

Species undergoing radiation in diverse environments often pose difficult challenges for taxon delimitation. The genus Camassia traditionally encompasses six North American species and multiple subspecies that have ecological and cultural-ethnobotanical importance and are known today as camas, camas lilies, or wild hyacinths. Twelve of the 14 currently recognized taxa occur far west of the Rockies in seasonally wet soils, exhibiting extensive morphological variability as well as geographic and habitat differentiation. Our exploration of genetic, morphological, and ecological data sets is revealing hidden complexity across the genus that poses challenging taxonomic puzzles. Here we aim to address a particular case study involving specific and subspecific delimitation of western populations nested within the floristically diverse region of northern California and southern Oregon. Of interest is the effectiveness and veracity of current taxonomic delimitations of C. howellii, C. leichtlinii, and C. quamash, including the multiple species and subspecies present in California and southwestern Oregon. To inform morphometric, population genetic, and phylogenetic analyses, we collected morphological data from extant populations throughout the region from the same plants and sites sampled for molecular genetic data. We also scored diverse character sets, including ecological data, from large samples of herbarium specimens. Although these western species are distinct from eastern Camassia, extensive field study, analyses of herbarium data, and microsatellite markers revealed not only some unexpected trait differences, but also populations that either represent unusual range extensions or show variability that is likely influenced by hybridization or genetic drift. Several of the populations studied recently in the field are vouchered in monographs and floras; their unusual nature may explain some of the confusion in taxonomic identification that has influenced keys still in use today. As we integrate and extend discovery-based approaches to species delimitation, the new results should provide a more nuanced perspective of species boundaries and how they arise. These insights will also guide the development of new or revised keys that we hope will highlight tractable similarities and differences among both species and subspecies in Camassia.

Broader Impacts:

1 - Willamette University, Biology Department, Salem, OR, 97301, USA
2 - University of Cincinnati, Department of Biological Sciences, 614 Rieveschl Hall, Cincinnati, OH, 45221-0006, USA
3 - University of Kansas, RL McGregor Herbarium & Bridwell Botanical Research Lab, McGregor Herbarium, 2045 Constant Ave, Lawrence, KS, 66047-3729, USA

Keywords:
Agavaceae
Camassia
species delimitation
flora
integrative taxonomy
Asparagaceae.

Presentation Type: Oral Paper:Papers for Sections
Session: 48
Location: Elmwood/Riverside Hilton
Date: Wednesday, July 31st, 2013
Time: 1:45 PM
Number: 48002
Abstract ID:827
Candidate for Awards:None