Format: ORAL

Lisa Pokorny1,3, Jaume Pellicer2,3, Yannick Woudstra3,4, Maarten J. M. Christenhusz3,5, Teresa Garnatje2,6, Luis Palazzesi7, Matthew G. Johnson8, Olivier Maurin3, Elaine Franoso3, Shyamali Roy3, Ilia J. Leitch3, Flix Forest3, William J. Baker3, and Oriane Hidalgo2,3

1 Real Jardín Botánico (RJB-CSIC), Madrid, Spain 2 Institut Botànic de Barcelona (IBB), CSIC-Ajuntament de Barcelona, Barcelona, Spain 3 Royal Botanic Gardens, Kew, Richmond, United Kingdom 4 Natural History Museum of Denmark, Copenhagen, Denmark 5 Curtin University, Perth, Australia 6 Jardí Botànic Marimurtra – Fundació Carl Faust, Blanes, Spain 7 Museo Argentino de Ciencias Naturales, CONICET, Buenos Aires, Argentina 8 Texas Tech University, Lubbock (TX), USA

Reconstructing evolutionary trajectories and transitions that have shaped floral diversity relies heavily on the phylogenetic framework on which traits are modelled. In this study, we focus on the angiosperm order Ranunculales, sister to all other eudicots, to unravel higher-level relationships, especially those tied to evolutionary transitions in flower symmetry within the family Papaveraceae. This family presents an astonishing array of floral diversity, with actinomorphic, disymmetric (two perpendicular axes of symmetry), and zygomorphic flowers. We generated nuclear and plastid datasets using the Angiosperms353 universal probe set for target capture sequencing (of 353 single-copy nuclear ortholog genes), together with publicly available transcriptome and plastome data mined from open access online repositories. We relied on the fossil record of the order Ranunculales to date our phylogenies and to establish a timeline of events. Our phylogenomic workflow shows that nuclear-plastid incongruence accompanies topological uncertainties in Ranunculales. A cocktail of incomplete lineage sorting, post-hybridization introgression, and extinction following rapid speciation most likely explain the observed knots in the topology. These knots coincide with major floral symmetry transitions and thus obscure the order of evolutionary events.