This name is a synonym of Rhynchospora rugosa subsp. americana (Guagl.) Govaerts.
The record derives from WCSP
(data supplied on 2012-03-23)
which reports it as a synonym (record 261578) with original publication details: Darwiniana 22: 272 1979.
Full publication details for this name can be found in IPNI: http://ipni.org/urn:lsid:ipni.org:names:220200-2.
This name was in version 1 of The Plant List, record kew-261578, and has not been changed.