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 252641) with original publication details: J. Linn. Soc., Bot. 42: 180 1914.
Full publication details for this name can be found in IPNI: http://ipni.org/urn:lsid:ipni.org:names:310310-1.
This name was in version 1 of The Plant List, record kew-252641, and has not been changed.