Plectranthus cylindraceus Hochst. ex Benth.

POWO follows these authorities in synonymising this name:

• Darbyshire, I., Kordofani, M., Farag, I., Candiga, R. & Pickering, H. (eds.) (2015). The Plants of Sudan and South Sudan: 1-400. Kew publishing, Royal Botanic Gardens, Kew. [Cited as Plectranthus montanus.]
• Hedberg, I., Friis, I. & Persson, E. (2009). Flora of Ethiopia and Eritrea 1: 1-305. The National Herbarium, Addis Ababa University, Ethiopia & The Department of Systematic Botany, Upps. [Cited as Plectranthus montanus.]
• Mosti, S., Raffaelli, M. & Tardelli, M. (2012). Contributions to the flora of central-southern Dhofar (Sultanate of Oman). Webbia; Raccolta de Scritti Botanici 67: 65-91. [Cited as Plectranthus montanus.]
• Thulin, M. (ed.) (2006). Flora of Somalia 3: 1-626. The Royal Botanic Gardens, Kew. [Cited as Plectranthus montanus.]
• van Jaarsveld, E. (2006). The Southern African Plectranthus and the art of turning shade to glade: 1-176. Ferwood Press, Simon's Town, South Africa. [Cited as Plectranthus montanus.]

This name was accepted following an alternative taxonomy by these authorities:

• Calane da Silva, M., Izdine, S. & Amuse, A.B. (2004). A Preliminary Checklist of the Vascular Plants of Mozambique: 1-184. SABONET, Pretoria. [Cited as Plectranthus cylindraceus.]
• Govaerts, R. (2003). World Checklist of Selected Plant Families Database in ACCESS: 1-216203. The Board of Trustees of the Royal Botanic Gardens, Kew. [Cited as Plectranthus cylindraceus.]
• Hedberg, I., Kelbessa, E., Edwards, S., Demissew, S. & Persson, E. (eds.) (2006). Flora of Ethiopia and Eritrea 5: 1-690. The National Herbarium, Addis Ababa University, Ethiopia & The Department of Systematic Botany, Upps. [Cited as Plectranthus cylindraceus.]
• Rahman, M.A. & al. (2002). Notes on succulent plant species of Saudi Arabia. Bangladesh Journal of Plant Taxonomy 9(1): 25-40. [Cited as Plectranthus cylindraceus.]