Molecular phylogenetics, historical biogeography and character evolution in Dyckia (Bromeliaceae, Pitcairnioideae)

Dyckia is a xeromorphic bromeliad genus with 168 species distributed throughout south-eastern South America, with the centre of diversity in Brazil. Previous phylogenetic studies based on sequence data revealed, in general, poor resolution among species. To improve our understanding of infrageneric relationships, here we present a molecular phylogenetic analysis of Dyckia based on amplified fragment length polymorphism (AFLP) markers. We also discuss the evolution of floral characters and their implications for the life-history of the genus. Dyckia proved to be well supported as a monophyletic group, although showing a poor resolution in the backbone of the tree. In accordance with previous data, our results suggest that hybridization and introgression have played a significant role in the evolution of the genus. However, the AFLP data showed stronger support for terminal nodes. The results provided deeper insights into the infrageneric relationships, the correlation between species groups, morphological aspects and geographical distribution. Additionally, the character reconstruction corroborates the geographical association found, in which a pattern could generally be observed for species stated as early diverging. Analysing the genus at a population level and taxonomic revision are crucial to understanding the evolutionary dynamics of the clade. (C) 2016 The Linnean Society of London, Botanical Journal of the Linnean Society, 2016