This name is a synonym of Senecio haworthii (Sweet) Sch.Bip..
The record derives from TICA
(data supplied on 2012-02-11)
which reports it as a synonym (record 18B92BDB-AA81-4589-91B7-ED9A6E78E438) with original publication details: Prodr. (DC.) 6: 338 338 1838.
Full publication details for this name can be found in IPNI: http://ipni.org/urn:lsid:ipni.org:names:227390-1.
This name was in version 1 of The Plant List, record gcc-137069, and has not been changed.