This name is a synonym of Centaurea stoebe L..
The record derives from TICA
(data supplied on 2012-02-11)
which reports it as a synonym (record 952ED343-C870-4875-BEAA-8AA5894E7719).
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 rhenana in version 1 of The Plant List.