Submitted to: International Botanical Congress
Publication Type: Abstract Only
Publication Acceptance Date: April 13, 2011
Publication Date: N/A
Interpretive Summary: The Cocoseae, a tribe of the palm family contains a number of palms with significant economic importance, including the coconut and oil palm. Using seven single copy genes, we previously inferred a well resolved genealogy its subtribe Attaleinae. In that study, we showed that the genus Syagrus is the most closely related group to the coconut. We now extend our sequence analysis across the entire tribe, and discuss the relationships revealed and how they impact the current classification of the palm family.
Technical Abstract: The Cocoseae is one of 13 tribes of Arecaceae subfam. Arecoideae, and contains a number of palms with significant economic importance, including the monotypic and pantropical Cocos nucifera, the coconut, and African oil palm (Elaeis guineensis). Using seven single copy WRKY transcription factor genes, we previously inferred a well resolved phylogeny and chronology of the subtribe Attaleinae. In that study, we resolved a monophyletic relict African clade as sister to the American genera, including Cocos. We determined that Lytocaryum is best treated as part of Syagrus, resolved Syagrus sensu lato as sister to Cocos, and presented a novel clade uniting Parajubaea with Butia and Jubaea that is also supported by leaf anatomical data. Branch nodes were congruent with major paleogeographic events. We now extend our sequence analysis across the entire tribe, with Roystonea and Reinhardtia as outgroups. Three subtribes, Attaleinae, Bactridinae and Elaeidinae are consistantly resolved with strong support. The monotypic Amazonian Barcella is sister to Elaeis. The genus Hexopetion is well supported as distinct from Astrocaryum. The inclusion of Gastrococos in Acrocomia is also supported. Two methods of species tree generation will be compared: gene tree parsimony with DupTree, and Bayesian approximation with BEST. A scenario for the overall biogeograpic and evolutionary history of the tribe will be presented.