Abstract Detail

Systematics

Everett, Amanda [1], Simpson, Michael [1].

The Phylogeny of Pogogyne (Lamiaceae): An Evolutionary Analysis Comparing Two Next Generation Sequencing Methodologies.

Pogogyne is a small genus (eight described species) of annuals in the mint family (Lamiaceae). The etymology of the name ‘Pogogyne’ derives from Greek roots, and means “bearded woman”. Indeed, these intoxicatingly pungent little herbs all have a style that is lined with trichomes. Pogogyne species are specialists within ephemerally wet habitats, such as vernal pools or seasonally wet meadows, and are distributed throughout such habitats within the California Floristic Province. The genus is a monophyletic lineage estimated to have diverged roughly 0.9 to 1.9 mya. Phylogenetic research places Pogogyne sister to Acanthomintha and Monardella within sub-tribe Menthineae, subfamily Nepetoideae. Our understanding of the relationships within Pogogyne has been previously obscured by the limited availability of markers with adequate phylogenetic signal. In the only phylogenetic study of this genus 30 nodes are recovered, although about half are strongly supported. As Next Generation Sequencing becomes more commonly used, sequence alignments are reaching sizes that were previously inconceivable. As a result, many recalcitrant phylogenies are being revisited with new data and bioinformatics. Here, using sequence data obtained with ddRADseq, the phylogeny of Pogogyne is revisited using Maximum Likelihood and Bayesian Inference. The resulting tree is compared with trees produced using the same phylogenetic methods applied to genome skimming data. Both data types yield trees with the majority of nodes having high support. The trees derived from plastome and cistron genome skimming data conflict, however, while the concatenated ddRADseq supermatrix produces a single tree with better support values than the preliminary genome skimming analysis. Phylogenetic results from the ddRADseq dataset are then used to infer biogeographical patterns and to re-evaluate divergence times. Multiple new, geographically restricted taxa are uncovered by this analysis. Findings will also contribute to the understanding of evolution and biodiversity in the vernal pool habitat, which is in critical decline.

1 - San Diego State University, Biology, 5500 Campanile Drive, San Diego, CA, 92182, USA

Keywords:
ddRADseq
genome skimming
Pogogyne
plant systematics.

Presentation Type: Oral Paper
Session: 21, Cooley Awards I
Location: 201/Savannah International Trade and Convention Center
Date: Tuesday, August 2nd, 2016
Time: 10:45 AM
Number: 21011
Abstract ID:449
Candidate for Awards:George R. Cooley Award