This name is a synonym of Carex atrofusca subsp. minor (Boott) T.Koyama.
The record derives from WCSP
(data supplied on 2012-03-23)
which reports it as a synonym (record 224775) with original publication details: Pflanzenr. IV, 20(38): 554 1909.
This name was in version 1 of The Plant List, record kew-224775.