Abstract Detail

Systematics Section/ASPT

Vargas, Oscar M. [1], Simpson, Beryl [2].

Explosive Radiation Phylogeny of the Andean Genus Diplostephium Elucidated by High-throughput Sequencing: Insight into Paramo Plant Evolution and the Discovery of at Least One New genus.

Taxa in which recent explosive radiation has occurred are characterized by having very low molecular divergence and high morphological plasticity. This recency poses a problem for systematic biology because of the amount of sequence data needed in order to assess the molecular phylogeny of these groups. In this study, we employed the use of whole genome high-throughput sequencing to elucidate the phylogeny of the genus Diplostephium and its allies (Compositae). The genus comprises ca. 111 species of small trees and shrubs distributed throughout paramos and mountain habitats of the central and northern Andes, the Sierra Nevada of Santa Marta in Colombia, and the mountains of Costa Rica. By using 2x100 libraries in an Illumina 2500 and targeting a minimum of 8 million reads per sample, we were able to assemble de-novo the complete chloroplast genome, a part of the mitochondrial genome, and a ~9 kb of nrDNA that includes the ETS, ITS, and NTS regions for phylogenetic analysis. Our results showed the utility of using these three datasets obtained by high-throughput sequencing for phylogenetic reconstruction of recently radiated groups. Our topologies suggest that Diplostehium is polyphyletic, necessitating the description of at least one new genus. In addition, our data shows a remarkably high morphological convergence in different lineages following colonization of similar habitats.

Related Links:
First author and project website

1 - The University of Texas at Austin, Integrative Biology and Plant Resources Center, 205 W 24th Street, Austin, TX, 78712, USA
2 - The University of Texas at Austin, Integrative Biology and Plant Resources Center, 205 W 24th Street, Austin, Texas, 78712, USA

Keywords:
paramo
Diplostephium
Astereae
Compositae
Asteraceae
Andes
High-throughput Sequencing
Genome skimming
Explosive radiation
chloroplast genome
nuclear ribosomal DNA
mitochondrial genome.

Presentation Type: Oral Paper:Papers for Sections
Session: 49
Location: Salon 4/The Shaw Conference Centre
Date: Tuesday, July 28th, 2015
Time: 2:45 PM
Number: 49006
Abstract ID:168
Candidate for Awards:George R. Cooley Award