Abstract Detail

Systematics Section

Smith, James F. [1], Clark, John L. [2], Amaya M., Marisol [3].

A preliminary new classification system for the species of Columnea.

Columnea is the largest genus in terms of number of species in the New World Gesneriaceae.  Classification of Columnea as one genus or as separate genera has been controversial. Wiehler  recognized a classification system based on vegetative, fruit, and  floral characters and opted to divide Columnea into four genera: Columnea, Trichantha, Dalbergaria,  and Pentadenia.  He added a fifth genus to the complex by describing two species in the genus Bucinellina.  This classification was not widely accepted and Wiehler's genera were considered sections within the genus Columnea.  Pentadenia was split into two sections: Pentadenia with robust herbs and large ventricose corollas, and Stygnanthe with creeping herbaceous plants and narrow corollas. Bucinellina was never formally placed, but was considered close to the species of section Ortholoma (Wiehler's Trichantha).  Molecular work since 1994 that sampled more than a single species of Columnea has always resolved the genus as monophyletic.  Unfortunately, sporadic and uneven sampling, as well as limited data prevented a good test of the classification system within the genus. We propose a preliminary classification system that recognizes seven sections.  This modified classification is based on a sampling of 35 species and sequences of ITS and six rapidly evolving chloroplast regions.  The clades that represent the new sections are all strongly supported based on parsimony and Bayesian analyses.  Sections Columnea and Collandra are largely unchanged, consisting of the species Wiehler named as genera (Columnea and Dalbergaria).  Sections Pentadenia and Ortholoma are split into two sections each and some of the species of Ortholoma are likely to be moved to Stygnanthe. Bucinellina paramicola nests within one of the Ortholoma sections based on our molecular data.

Broader Impacts:

1 - Boise State University, Department of Biological Sciences, 1910 University Drive, Boise, Idaho, 83725-1515
2 - University of Alabama, Department of Biological Sciences, Box 870345, Tuscaloosa, AL, 35487, USA
3 - Universidad Nacional de Colombia, Instituto de Ciencias Naturales, Bogota, Colombia

Keywords:
Columnea
Gesneriaceae
South America
phylogeny.

Presentation Type: Oral Paper:Papers for Sections
Session: 50
Location: 555A/Convention Center
Date: Wednesday, August 4th, 2010
Time: 10:00 AM
Number: 50008
Abstract ID:641