This name is a synonym of Adenostemma caffrum var. longifolium (Chiov.) S.A.L.Sm..
The record derives from TICA
(data supplied on 2012-02-11)
which reports it as a synonym (record 452710E5-1F17-4C4A-8F29-C72522610443) with original publication details: 62 1935.
Full publication details for this name can be found in IPNI: http://ipni.org/urn:lsid:ipni.org:names:77066313-1.
This name was in version 1 of The Plant List, record gcc-65490, and has not been changed.