This name is a synonym of Carex atrata subsp. longistolonifera (Kük.) S.Yun Liang.
The record derives from WCSP
(data supplied on 2012-03-23)
which reports it as a synonym (record 224750) with original publication details: Pflanzenr. IV, 20(38): 400 1909.
This name was in version 1 of The Plant List, record kew-224750.