Format: ORAL

Simon Verlynde 1,2*, Gregory M. Plunkett 1 Tariq Stvart 3,4,5

1 Cullman Program for Molecular Systematics, New York Botanical Garden, Bronx, New York 10458-5126, U.S.A. 2 PhD Program in Biology, Graduate Center, City University of New York, 365 5th Ave., New York, NY 10016, U.S.A. 3 Herbarium et Bibliothèque de Botanique africaine, Université Libre de Bruxelles, campus de la Plaine, boulevard du Triomphe, CP 265, B-1050, Brussels, Belgium. 4 Missouri Botanical Garden, Africa & Madagascar Department, 4344 Shaw Blvd., St. Louis, MO 63110, U.S.A. 5 Botanic Garden Meise, Domein van Bouchout, Nieuwelaan 38, B-1860 Meise, Belgium. *corresponding author: sverlynde@nybg.org

Recent attempts to classify Angraecum, the largest genus of Angraecinae (Epidendroideae, Vandae), have fallen short due to a lack of molecular sampling and of molecular characters as well as the paucity of available voucher material. Without a robust natural classification, however, the reconstruction of the evolutionary history of Angraecum is impaired. Using a new multi-locus dataset collected with the Angiosperm353 bait set, augmented by a comprehensive sampling now available through the orchid shade house network of the Missouri Botanical Garden in Madagascar, in parallel to extensive field work conducted on the Mascarene islands and East Africa, we aimed to revise the genus Angraecum, improving its classification and testing phylogenetic hypotheses. Using resulting data from Hyb-Seq, our analyses consistently retrieved a strongly supported clade grouping most Angraecum species from Madagascar and the Western Indian Ocean, but interestingly including species from three other Malagasy genera, Lemurorchis, Oeoniella and Sobennikoffia. Moreover, the resulting phylogenies allowed us to re-circumscribe sections and better understand intersectional relationships. Finally, a group of fifteen species were found to be polyphyletic and were described as a new genus, Vavavoloina.