|Meve, U; Liede-Schumann, S: Taxonomy of the Andean genus Pentacyphus (Apocynaceae: Asclepiadeae–Pentacyphinae), Plant Systematics and Evolution, 301, 997-1004 (2015)|
Taxonomy of the northern Andean genera Pentacyphus and Tetraphysa is re-evaluated by morphological and molecular analyzes. Pentacyphus, while having priority against its synonym Tetraphysa, consists of three species: P. andinus, P. lehmannii, and P. camargoi, based on Sarcostemma camargoi, a species from Colombia and Ecuador which is transferred to Pentacyphus here. Moreover, T. tamana is reduced to subspecific rank under P. lehmannii, and an additional subspecies with exceptionally large flowers and corona lobes is newly described as P. lehmannii subsp. elongatus. P. boliviensis, a synonym of P. andinus, is lectotypified.