This name is a synonym of Centaurea aspera subsp. gentilii (Braun-Blanq. & Maire) Dobignard.
The record derives from TICA
(data supplied on 2012-02-11)
which reports it as a synonym (record BEF0B607-7DEE-4453-BF44-011157520F85).
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 Centaurea gentilii in version 1 of The Plant List.