Abstract
Memecylon sect. Buxifolia R.D. Stone (Melastomataceae, Olisbeoideae) is a group of forest shrubs and small understory trees distributed from tropical East Africa (Kenya and Tanzania) to eastern South Africa and with a disjunct occurrence in Madagascar. Previous authors had recognized three species of this section as occurring in Mozambique, i.e., M. natalense Markgr., M. torrei A. Fern. & R. Fern. and M. insulare A. Fern. & R. Fern. Here we describe four new species of M. sect. Buxifolia from Mozambique and adjacent parts of Malawi and Tanzania: Memecylon incisilobum R.D. Stone & I.G. Mona, M. nubigenum R.D. Stone & I.G. Mona, M. rovumense R.D. Stone & I.G. Mona and M. aenigmaticum R.D. Stone. In accordance with previous molecular results, M. incisilobum and M. nubigenum are semi-cryptic species that had been confused with M. natalense (considered here to be a South African endemic). Memecylon rovumense and M. aenigmaticum had also been confused with M. natalense, but their conspicuously verrucose-wrinkled fruits indicate a closer affinity with M. torrei. We assess the conservation status of each new species according to the IUCN Categories and Criteria, and provide an identification key to the seven species of Memecylon currently recognized in the flora of Mozambique.