A molecular phylogenetic study of African members of tribe Hypolytreae (Mapanioideae, Cyperaceae)

Abstract

Abstract Mapanoioideae are one of two subfamilies of Cyperaceae and consist of 186 species. Molecular phylogenetic relationships in subfamily Cyperoideae have recently been studied well, whereas evolutionary relationships in Mapanioideae remain little known. Subfamily Mapanioideae include two tribes. This study focuses on Hypolytreae, which is represented by three genera in Africa (Hypolytrum, Mapania and Principina). In this paper, we present the first molecular phylogenetic study of African Hypolytreae using a Sanger sequencing approach. We aim to (1) test whether Hypolytrum, Mapania and Principina are reciprocally monophyletic; (2) investigate whether the morphologically based sections in Hypolytrum and Mapania represent monophyletic taxa; (3) resolve species delimitation where multiple accessions could be sequenced and (4) explore the relationships of species occurring in West Tropical Africa vs. Central Africa. Our phylogenetic analyses strongly support Mapania and Hypolytrum as separate genera, but Principina is nested in Hypolytrum. This result is consistent with morphological differences. Mapania spp. are obligate rainforest species, but our results show that species from West Tropical Africa and species from Central Africa do not form separate clades. Dispersal between these regions may have happened during interglacial periods when the rainforest was continuous.