This member of the Apocynaceae family was given this name by Nicholas Edward Brown and Otto Stapf in 1908. It is found in Angola, Cameroon, Malawi, Mozambique, Zaïre and Zimbabwe, growing in a well drained but rather rich soil with some water and lots of sun. The caudex can grow to fifteen centimetres in diameter, the entire plant to ten centimetres in height. The flowers are purple. The genera name from Greek rhaphis; 'beet-root' and akme; 'sharpness' possibly referring to the taste of the roots - haven't tried yet. The species name means 'useful' as it can be eaten. *)Accordantly to the latest taxonomic system; APG IV 2016, Asclepiadaceae is now part of the Apocynaceae. A significantly different looking plant by B.T. Wursten, Mozambiqueflora.com, who usually is right.

