This name is a synonym of Kleinia grantii (Oliv. & Hiern) Hook.f..
The record derives from TICA
(data supplied on 2012-02-11)
which reports it as a synonym (record C92615ED-1E17-4DFB-B4A4-14095273F55D).
This name record (from TICA) was not included in version 1 of The Plant List. It is possible the same name was included from a different data source, to check this you can search for Senecio longipes in version 1 of The Plant List.