Three species of Coleus (Lamiaceae) from the Guinean Highlands: a new species, a new combination and clarification of Coleus splendidus

Abstract

Species delineation and taxonomic status of three species of Coleus Lour. from the Guinean Highlands, West Africa, are discussed in the context of related taxa. A new species, C. ferricola Phillipson, O.Hooper & A.J.Paton, is found on iron-rich substrates. The related C. splendidus A.Chev. is recognised as a distinct species with C. djalonensis A.Chev. and C. peulhorum A.Chev. var. violacea A.Chev. placed in synonymy. The new combination, Coleus lateriticola (A.Chev.) Phillipson, O.Hooper & A.J.Paton, based on Solenostemon lateriticola A.Chev., but frequently treated at subspecific rank under Plectranthus monostachyus (P.Beauv.) B.J.Pollard, is established. These taxa are described and discussed, and distribution data, illustrations and IUCN Red List assessments are also provided.