Abstract Detail

Systematics Section

Plumb, Rachel [1], Sanders, Jeffrey C. [2], Moore, Michael J. [1].

Phylogenetics and phylogeography in a gypsophilic clade: Haploësthes and Sartwellia (Asteraceae: Flaveriinae).

The three genera Flaveria, Haploësthes, and Sartwellia constitute the monophyletic subtribe Flaveriinae, which have a Chihuahuan Desert center of distribution. Many taxa within Flaveriinae are gypsophilic (endemic to gypsum), including most taxa within Sartwellia and Haploësthes. Flaveriinae and other Chihuahuan Desert gypsophilic plant groups are geographically widespread, despite the island-like distribution of gypsum outcrops in the Chihuahuan Desert. Morphological and phylogeographic evidence suggests that these widespread gypsophiles may be relatively old. As a first step toward understanding the phylogeography of gypsophily within Haploësthes and Sartwellia, we reconstructed a comprehensive phylogeny of these genera to address the following questions: 1) Is each genus within Flaveriinae monophyletic? 2) Has gypsophily evolved repeatedly within Haploësthes and Sartwellia, or does a single origin best explain the modern pattern of gypsophily in these genera? 3) Do geographically isolated populations of gypsophilic species within these two genera display evidence of interpopulational sequence divergence, suggesting relative lack of gene flow as might be expected given the geographic isolation of differing gypsum deposits? To address these questions, we reconstructed the phylogeny of Flaveriinae by generating and analyzing DNA sequences for ITS and six chloroplast spacer regions. Preliminary ITS results indicate that Haploësthes and Sartwellia are monophyletic, but that Flaveria is not; the Grand Canyon endemic F. macdougallii is sister to Haploësthes. At least some geographic structure is also evident within both Haploësthes and Sartwellia in the ITS tree.

Broader Impacts:

Related Links:
Michael Moore Research

1 - Oberlin College, Biology Department, 119 Woodland St., Science Center, K123, Oberlin, OH, 44074
2 - Oberlin College, Biology Department, 119 Woodland St., Oberlin, OH, 44074, USA

Keywords:
gypsophilic
phylogeography
Flaveriinae
Chihuahuan Desert.

Presentation Type: Poster:Posters for Sections
Session: P
Location: Hall A/Convention Center
Date: Monday, August 2nd, 2010
Time: 5:30 PM
Number: PSY006
Abstract ID:316