This name is a synonym of Carex aquatilis var. dives (Holm) Kük..
The record derives from WCSP
(data supplied on 2012-03-23)
which reports it as a synonym (record 226130) with original publication details: Amer. J. Sci. IV, 17: 312 1904.
Full publication details for this name can be found in IPNI: http://ipni.org/urn:lsid:ipni.org:names:274051-2.
This name was in version 1 of The Plant List, record kew-226130, and has not been changed.