Format: ORAL

Seraina E. Rodewald1, David-Paul Klein2, Ronen Shtein3, Gideon F. Smith4, Rokiman Letsara5, Gudrun Kadereit1

1 Ludwig-Maximilians-Universität München, Germany 2 Humboldt University zu Berlin, Berlin, Germany 3 Tel Aviv University, Tel Aviv, Israel 4 Department of Botany, Nelson Mandela University, Gqeberha, South Africa 5 Parc Botanique et Zoologique de Tsimbazaza & École supérieur Polytechnique d'Antananarivo, Antananarivo, Madagascar seraina.rodewald@lmu.de

Kalanchoe (Crassulaceae) is a diverse genus native to Madagascar and Africa, and to a lesser extent, the Arabian Peninsula and tropical southeast Asia. The genus is known as a model system for CAM photosynthesis and vegetative reproduction as well as for its horticultural value, invasive potential and use in traditional medicine. Surprisingly, however, Kalanchoe lacks a reliable phylogenetic framework. To address this issue, we inferred a phylogeny based on ddRADseq data representing 70% of the taxa recognised in the genus. We recovered four major clades, broadly corresponding to the current subgeneric classification, with exceptions. The recently reinstated subgenus Calophygia resolves as sister to the rest of the genus, and the predominantly mainland-African subgenus Kalanchoe forms a strongly supported monophyletic clade. However, the relationship among the remaining two clades containing species from subgenera Bryophyllum, Kitchingia and Pubescentes, receives less support. A Malagasy origin of the genus is confirmed, from where the African continent was colonised only once, with two subsequent dispersals each to the Arabian Peninsula and tropical southeast Asia. The production of bulbils on the leaf margin was found to be an apomorphy within the subgenus Bryophyllum while propagules on the inflorescence can occasionally be found in all four major clades.