Abstract Detail

Systematics

Stoughton, Thomas [1].

Evolution and Systematics of Claytonia lanceolata sensu lato (Montiaceae).

Tuberous perennial spring beauties, genus Claytonia L. (Montiaceae), grow in both North America and Eastern Asia. At least in western North America, these captivating geophytes are exceptionally variable (cyto)genetically, edaphologically, and morphologically. Claytonia lanceolata Pursh was considered the most enigmatic of the North America perennial species by some early taxonomists. Overall diversity is not well understood in the genus, owing at least in part to the ubiquity of polypoidy, putatively stemming from repeated bouts of secondary contact, hybridization, and introgression during Pleistocene pluvial oscillations. Claytonia recently underwent significant taxonomic review, resulting in a useful monograph that provides extremely helpful summary information about Claytonia, but lumps significant variation among other western North American species into the single taxon, C. lanceolata (with numerous synonyms). In the current study, a thorough review of C. lanceolata sensu lato is conducted, including extensive field, molecular, morphological, and edaphological investigations, to bolster our understanding of species boundaries for enhanced taxonomic circumscription. Analyses include: (1) phylogeny estimation using Sanger and Next Generation Sequencing data (ddRAD, genome skim), (2) morphometric analyses, including elliptical fourier analysis of leaf shape, and (3) soil chemistry assays to determine degrees of niche differentiation among closely related taxa. I described two new species, just a small fraction of the lineage diversity in California. Claytonia lanceolata var. peirsonii Munz & Johnston is included in a new combination for a primarily southern California species group comprising four subspecific taxa, three of which are new to science. Finally, Claytonia obovata Rydberg is segregated from C. lanceolata in California, resurrected but with an enriched understanding of its evolution. Information about inter- and intra-specific relationships, in combination with our understanding of the geologic history of western North America, is used in this study to reflect on how plant species and their geographic ranges change over time.

1 - Claremont Graduate University, 1500 N. College Avenue, Claremont, CA, 91711, USA

Keywords:
Rare Plants
reticulate evolution
Genetic diversity
genome skimming
phylogenomics
polyploidy
ddRADseq
diversification
biodiversity
California
Caryophyllales
edaphic endemism
endemic/rare
hybridization
morphology
Montiaceae
new species
Next generation sequencing
ordination
species boundaries
Species complex
species tree
Systematics
taxonomy
variation.

Presentation Type: Oral Paper
Session: 21, Cooley Awards I
Location: 201/Savannah International Trade and Convention Center
Date: Tuesday, August 2nd, 2016
Time: 11:00 AM
Number: 21012
Abstract ID:509
Candidate for Awards:George R. Cooley Award