This name is a synonym of Haplopappus hookerianus (Torr. & A.Gray) A.Gray.
The record derives from TICA
(data supplied on 2012-02-11)
which reports it as a synonym (record 739745DC-65EA-46B9-8AB4-23DC4480C178) with original publication details: Revis. Gen. Pl. 1 318 1891.
Full publication details for this name can be found in IPNI: http://ipni.org/urn:lsid:ipni.org:names:23553-2.
This name was in version 1 of The Plant List, record gcc-19401, and has not been changed.