Systematics/Phytogeography / Taxonomie/ Section
Ghebretinsae, Amanuel , Graham, Shirley A. , Barber, Janet C. .
Molecular phylogenetics of Cuphea: evolution of floral morphology, chromosome number, seed and pollen characters and habit.
Cuphea (Lythraceae) comprises ca. 270 species distributed from the southern US to eastern Argentina. The genus is of growing economic importance because the seeds produce highly diversified oils that are rich in a variety of medium-chain fatty acids, which find worldwide use in industrial feed-stocks, and especially in the detergent and cosmetics industries. Sequences from the internal transcribed spacer (ITS) of the nrDNA and two cpDNA regions (trnL-trnF spacer and trnL intron) were used to reconstruct phylogenetic relationships among 80 species of Cuphea and closely related genera. Our results show that Pleurophora is strongly supported as a sister genus to Cuphea. The data also support the subdivision of Cuphea into two major lineages. Three of the 13 sections recognized in existing classifications (Heteranthus, Trispermum and Pseudocircaea) are supported as monophyletic, but all are nested within the large Euandra/ Brachyandra/ Melvilla clade. Our analyses also indicate that Cuphea originated in South America and subsequently dispersed into the Caribbean and North America. There were three or more independent introductions into North America, and at least three introductions into the Greater Antilles. The evolution of characters such as annual versus perennial habit, seed size, specialization in floral morphology, tricolporate and diporate pollen grains, and chromosome number will be discussed within the phylogenetic framework.
Log in to add this item to your schedule
1 - Saint Louis University, Department of Biology, 3507 Laclede Avenue, St Louis, Missouri, 63103-2010, USA
2 - Missouri Botanical Garden, P.O. Box 299, St. Louis, Missouri, 63166-0299, USA
Presentation Type: Poster:Posters for Sections
Location: Ball Room & Party Room/SUB
Date: Monday, July 28th, 2008
Time: 12:30 PM