This name is a synonym of Sparganium angustifolium Michx..
The record derives from WCSP
(data supplied on 2012-03-26)
which reports it as a synonym (record 266005) with original publication details: Nat. Pfl.-Fam. Typhac. 27 1845.
Full publication details for this name can be found in IPNI: http://ipni.org/urn:lsid:ipni.org:names:836742-1.
This name was in version 1 of The Plant List, record kew-266005.