This name is a synonym of Costularia arundinacea (Sol. ex Vahl) Kük..
The record derives from WCSP
(data supplied on 2012-03-23)
which reports it as a synonym (record 234517) with original publication details: Repert. Spec. Nov. Regni Veg. 46: 31 1939.
Full publication details for this name can be found in IPNI: http://ipni.org/urn:lsid:ipni.org:names:303586-1.
This name was in version 1 of The Plant List, record kew-234517, and has not been changed.