Abstract Detail

Systematics Section/ASPT

Smith, James [1], Schulte, Lacie [2], Ooi, Maggie Tsing-Yu [2], Jeffries, Shandra [2], Prior, Carly [2], Amaya M., Marisol [3], Clark, John L. [4].

Reclassifying the subgeneric boundaries within Columnea (Gesneriaceae) to reflect evolutionary history.

Genera with large numbers of species pose unique challenges to understanding evolutionary history and the evolution of characters within such taxa. The underlying problem is sampling; all species should be sampled to adequately assess the evolutionary patterns. This is often infeasible for large taxa, and even for moderately large taxa this can be difficult if species are in remote geographic areas or areas that are logistically challenging to reach. In such cases, breaking the taxon into smaller, manageable numbers is a means of making the project tractable. The challenge here is to guarantee that the smaller groups are themselves monophyletic. The genus Columnea (Gesneriaceae) comprises an estimated 250-300 species distributed in the Neotropics with many narrow endemic species. There have been numerous subgeneric classifications proposed over the past 150 years, each relying on different characters to define sections within the genus in attempts to reflect evolutionary history. The present study analyses DNA sequence data from representatives of all previous phylogenetic classifications to test the monophyly of earlier systems. Species have also been selected to represent morphological and geographic variation within the genus. Phylogenetic analyses indicate that no previous classification system defined sections that were exclusively monophyletic. Sections Pentadenia, Columnea, and Collandra most closely correspond to monophyletic groups. Section Stygnanthe comprises two, relatively unrelated monophyletic clades and unsurprisingly, section Ortholoma is split into several clades. A new classification system is proposed that recircumscribes sections based on the phylogenetic analysis using morphological characters that are synapomorphies for each of the clades.

Broader Impacts:

1 - BOISE STATE UNIVERSITY, Biology Department, 1910 UNIVERSITY DRIVE, Boise, ID, 83725-1515, USA
2 - Boise State University, Biological Sciences, 1910 University Drive, Boise, ID, 83725, USA
3 - Universidad Nacional de Colombia, Instituto de Ciencias Naturales, Apartado 7495, Bogota, Colombia
4 - The University of Alabama, Biological Sciences, Box 870345, Tuscaloosa, AL, 35487, USA

Keywords:
Columnea
Gesneriaceae
phylogeny
classification
Neotropics.

Presentation Type: Oral Paper:Papers for Sections
Session: 49
Location: Marlborough A/Riverside Hilton
Date: Wednesday, July 31st, 2013
Time: 2:00 PM
Number: 49003
Abstract ID:137
Candidate for Awards:None