This name is a synonym of Sinapidendron rupestre Lowe.
The record derives from Tropicos
(data supplied on 2012-04-18)
which reports it as a synonym (record 100360806) with original publication details: Sommerfeltia 17: 8. 1993.
Full publication details for this name can be found in IPNI: http://ipni.org/urn:lsid:ipni.org:names:972494-1.
This name was in version 1 of The Plant List, record tro-100360806, and has not been changed.