This name is a synonym of Sparganium × oligocarpon Ångstr..
The record derives from WCSP
(data supplied on 2012-03-26)
which reports it as a synonym (record 266102) with original publication details: Syn. Mitteleur. Fl. 1: 292 1897.
This name was in version 1 of The Plant List, record kew-266102, and has not been changed.