This name is a synonym of Achillea santolinoides subsp. wilhelmsii (K.Koch) Greuter.
The record derives from TICA
(data supplied on 2012-02-11)
which reports it as a synonym (record 9E80BEFA-F687-4AD9-AD21-81AAFFD5D951) with original publication details: Linnaea 24 328 1851.
Full publication details for this name can be found in IPNI: http://ipni.org/urn:lsid:ipni.org:names:174355-1.
This name was in version 1 of The Plant List, record gcc-89416.