This name is a synonym of Haplopappus macrocephalus (Poepp. ex Less.) DC..
The record derives from TICA
(data supplied on 2012-02-11)
which reports it as a synonym (record 1BD3E565-5CB2-43DC-B03E-C5E2B4C6AB54) 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:23723-2.
This name was in version 1 of The Plant List, record gcc-119754, and has not been changed.