This name is a synonym of Phragmites australis subsp. altissimus (Benth.) Clayton.
The record derives from WCSP
(data supplied on 2012-03-23)
which reports it as a synonym (record 433926) with original publication details: Cas. Nár. Mus., Odd. Prír. 150: 140 1982.
Full publication details for this name can be found in IPNI: http://ipni.org/urn:lsid:ipni.org:names:921274-1.
This name was in version 1 of The Plant List, record kew-433926.