Format: ORAL

Cynthia Sothers1, Ghillean T. Prance2

C.A. Sothers¹, Royal Botanic Gardens, Kew, Richmond, UK; c.sothers@kew.org G.T. Prance², Royal Botanic Gardens, Kew, Richmond, UK.

Over the last years molecular phylogenetics has played a major role in the changing taxonomic landscape of the Chrysobalanaceae. The well-established morphological classification based on four tribes was upturned and genera previously thought to be closely related were found to be distantly related. Analyses using plastomes and more recently nuclear genomes show congruent results as well as incongruences across analyses. We aim to investigate these results and propose hypotheses on the evolutionary relationships of the well-supported clades and discuss putative reasons for the incongruence of some genera. Chrysobalanaceae has a pantropical distribution and comprises 540 species in 27 genera. The Neotropics harbours the greatest number of taxa, represented by over 400 species in 16 genera. Africa is represented by ca. 50 species in seven genera and Australasia ca. 60 species in ten genera. The megadiversity of the family in the lowland neotropics is discussed. It is among the top ten most abundant families in terra firme forests of the Amazon region. The flowers of all genera share one distinct and stable character, the gynobasic style, and diversity in floral morphology among genera centres on the position of the ovary on the receptacle (basal, apical, midway on wall of receptacle), number of ovary locules (1- or 2-locular), and presence/absence of petals. Parinari and Maranthes are the only two pantropical genera in the family and display distinct morphological adaptations for germination, a character lacking in the neotropical genera. The Neotropical-Australasian clade is the most enigmatic of the family, from a morphological and biogeographical viewpoint, and relationships among genera are still unclear. The clade is comprised of four species-poor genera, two Australasian and two neotropical genera.