Format: ORAL

LasC. Zeferino1,2,3, Flavia F. Pezzini2, Kyle G. Dexter3, Gwilym P. Lewis4 ,Ana Paula Fortuna-Perez1

1 Universidade Estadual Paulista “Julio de Mesquita Filho”, São Paulo, Brazil 2 Royal Botanic Garden Edinburgh, Edinburgh, United Kingdom 3 University of Edinburgh, Edinburgh, United Kingdom 4 Royal Botanic Gardens, Kew, United Kingdom

The genus Zornia J.F.Gmel is the second most speciose representative of the Adesmia clade (Leguminosae: Papilionoideae), with ca. 80 species. Zornia is the only genus within the clade with a global distribution, mainly occurring in tropical and subtropical regions of the world. A previous phylogeny for Zornia revealed that most species diverged in Brazil ca. 810 Mya, and suggested a single transoceanic dispersal event from the Americas to the Old World ca. 5 Mya. Here, we augment the previous phylogeny with new sampling from Central America, Asia, Africa and Oceania. We aimed to investigate evolutionary patterns of distribution in Zornia and answer biogeographic questions related to ancestral range estimation and evolutionary transitions between biomes. Our results suggest that Zorniaoriginated in the dry forest in Northeast Brazil. From there, the evolutionary path of the genus continued to the savannas of the Americas, where 40% of the present species occur. Lineages then adapted to the high elevation grassland in South America and Central America. The genus dispersed to the hight elevation grassland in Africa and then to the savannas in India and Australia. Our study shows the transoceanic dispersal occurred in Zornia, as previously it was not clear if this dispersal occurred from America to Africa or Australia first. We also clarify how the evolutionary transitions between biomes occurred in the genus, which is important to understand the dynamics of adaptation particularly to dry environments where Zornia mostly occurs.