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 406397) with original publication details: Ann. Sci. Observ. 2: 79 1829.
Full publication details for this name can be found in IPNI: http://ipni.org/urn:lsid:ipni.org:names:397097-1.
This name was in version 1 of The Plant List, record kew-406397.