Format: ORAL

Lovisa Thiln1, Olivier Lachenaud2,3, Sylvain Razafimandimbison4, Catarina Rydin1,5

1 Stockholm University, Stockholm, Sweden 2 Meise Botanic Garden, Meise, Belgium 3 Herbarium et Bibliothèque de Botanique Africaine, Université Libre de Bruxelles (ULB), Brussels, Belgium 4 Swedish Museum of Natural History, Stockholm, Sweden 5 Bergius Foundation, Stockholm, Sweden

Hymenocoleus is a small genus in the coffee family (Rubiaceae). It belongs to the pantropical tribe Palicoureeae of the subfamily Rubioideae, and the species of the genus are herbs or undershrubs restricted to rainforests in tropical Africa. Infrageneric relationships in Hymenocoleus have received limited attention since its description and phylogenetic relationships have never been investigated, but the genus has undergone a recent taxonomic revision, recognising 19 species. Several species are newly described and some are rare and as far as known endemic to narrow geographic ranges. Here we present the first phylogeny of Hymenocoleus, inferred using a phylogenomics approach. We used the Angiosperms353 probe set to capture hundreds of low-copy nuclear genes and inferred a species tree using coalescent-based methods. The result is a fully resolved, highly supported species-level phylogeny of Hymenocoleus. Data produced using the Angiosperms353 probe set here showed capable of resolving relationships in the genus, including some infraspecific relationships. Moreover, the topology proved robust to different analytical approaches, and use of different data partitions and filtering schemes. Hymenocoleus libericus is sister to the remaining species, however, incomplete lineage sorting is affecting the deepest splits in the genus and it is possible that cytonuclear discordance will be detected in future studies, for this node as well as a few others. It is further interesting to note that there is morphological support for several clades in the species tree.