This name is a synonym of Achillea pindicola subsp. integrifolia (Halácsy) Franzén.
The record derives from TICA
(data supplied on 2012-02-11)
which reports it as a synonym (record 5BAA98C0-2A8F-4455-B4D7-5F34990A9266) with original publication details: 243 1894.
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 Achillea clavennae in version 1 of The Plant List.