This name is a synonym of Carex sylvatica subsp. latifrons (V.I.Krecz.) Ö.Nilsson.
The record derives from WCSP
(data supplied on 2012-03-23)
which reports it as a synonym (record 231393) with original publication details: Allg. Bot. Z. Syst. 7: 31 1901.
This name was in version 1 of The Plant List, record kew-231393, and has not been changed.