A taxonomic revision of Petopentia (Apocynaceae: Periplocoideae)

AbstractThe generic name Petopentia Bullock is reinstated. Two species are recognized, namely Petopentia natalensis (Schltr.) Bullock, first described in 1894, and Petopentia undulata, a new species. Both species are found in the subtropical eastern region of South Africa, P. natalensis being associated with moist forest and P. undulata with drier lowveld savanna.Both species are climbers with root tubers, glabrous plant parts, glossy patently veined leaves with petioles and abaxial surfaces purple, pale yellow to pale green corollas with inverted tubes and purple pollinator guides.A taxonomic revision of the genus is presented which includes complete nomenclature and typification, generic and species descriptions, a key to the species and notes on geographic distribution and ecology