Synoptic revision of Kolobopetalum and Rhigiocarya (Menispermaceae) with the description of a new Kolobopetalum species from Gabon, and a new specific combination in Rhigiocarya from West Africa

Background and aims – In the framework of the Menispermaceae treatment for the Flore du Gabon, the closely related genera Kolobopetalum and Rhigiocarya are synoptically revised.Material and methods – Standard practices of herbarium taxonomy have been applied to study the relevant herbarium material from B, BM, BR, BRLU, HBG, K, L, P, U, and WAG. The relevant collecting data are stored in the Botany Section of the Naturalis Biodiversity Center, Leiden, The Netherlands.Key results – The distinction between the genera Kolobopetalum and Rhigiocarya is further investigated and improved. As a result, Kolobopetalum leonense is transferred to Rhigiocarya. The Gabonese collections of Kolobopetalum contained a new species named K. synsepalum, which is described and illustrated. Rhigiocarya nervosa is resurrected as a distinct species. The distribution of all species is mapped. Illustrations are provided to facilitate the use of the key for the two genera and their species.