Liede, S. & Nicholas, A. (1992) A Revision of the Genus Pentarrhinum E. Meyer (Asclepiadaceae) Kew Bulletin 47(3) 475-490
| Species | FZ divisions | Content | 
| abyssinicum Decne. subsp. abyssinicum | MS | Description, Image | 
| insipidum E. Mey. | MS (other?) | Description, Image |