Taxonomic treatment of Memecylon L. section Felixiocylon R.D.Stone (Melastomataceae), with descriptions of four new species from Cameroon, Gabon, and Equatorial Guinea (Bioko)

Jacques-Félix (1979) informally recognized the Memecylon normandii Jacq.-Fél. group with three species (M. normandii, M. macrodendron Gilg ex Engl., M. oubanguianum Jacq.-Fél.) from the forests of West and Central Africa. More recently this group has been formally treated as M. section Felixiocylon R.D.Stone. In this paper, four new species are described and illustrated for this section: M. korupense R.D.Stone, sp. nov. (South-West Region, Cameroon), M. fugax R.D.Stone, sp. nov. (South Region, Cameroon), M. alipes R.D.Stone, sp. nov. (Woleu-Ntem Province, Gabon & South Region, Cameroon), and M. biokoense R.D.Stone, sp. nov. (Bioko Sur Province, Equatorial Guinea). A lectotype is designated for M. macrodendron. New country-records are reported or confirmed for M. normandii (Nigeria), M. oubanguianum (Gabon, Congo-Kinshasa), and M. macrodendron (Gabon, Congo-Brazzaville). A key to the species of M. section Felixiocylon is provided, together with an assessment of conservation status for each species according to the criteria of the IUCN.