Format: ORAL

Seon-Hee Kim1, Koji Takayama1, Imai Ryosuke2, Masuda Sachiko3, Shibata Arisa3, Shirasu Ken3, Arnoldo Santos-Guerra4, Seung-Chul Kim5

1. Department of Botany, Graduate School of Science, Kyoto University, Kyoto, Japan, 2. Forest Research and Maintenance Organization, Matsunosato, Tsukuba, Ibaraki, Japan 3. RIKEN Center for Sustainable Resource Science, Yokohama, Kanagawa, Japan 4. Calle Guaidil 16, Tegueste, Tenerife, Canary Islands, Spain 5. Department of Biological Sciences, Sungkyunkwan University, Suwon, Republic of Korea

Numerous unique plant groups have made the Macaronesian Islands an exceptional area for studying evolution and speciation.Of several iconic angiosperm groups, the woody Sonchus alliance, which includes approximately 31 species in the Canaries, Madeira, and Cape Verde, represents one of the best-known examples of adaptive radiations. It has been difficult to unravel rapidly radiated interspecific relationships using conventional molecular markers (e.g., nrDNA ITS and chloroplast noncoding regions) due to the insufficient resolution and support. In order to clarify the biogeographic and evolutionary history of the alliance, we used the complete chloroplast genome and double-digest restriction site-associated DNA sequence (ddRAD-seq) data based on the thorough species coverage and multiple populations per species.The complete plastome sequences of 135 accessions provided well resolved strongly supported phylogenetic relationships but revealed non-monophyly of numerous species and unusual species relationships, suggesting rampant chloroplast polymorphisms. As previously suggested, the early divergence of segregate genera, Sventenia, Chrysoprenanthes, Babcockia, and Lactucosonchus, was supported. With 95 accessions, ddRAD-seq data also provided a fully resolved and highly supported phylogenetic framework for the alliance, while better reflecting species morphological and biogeographic relationships and revealing monophyly in most species. Newly inferred species relationships, timing of lineage divergence, and biogeographic history of the alliance based on the genome-wide nuclear data will be presented.