This name is a synonym of Diphasiastrum alpinum var. planiramulosum (Takeda) Li & J.Z. Wang.
The record derives from Tropicos
(data supplied on 2012-04-18)
which reports it as a synonym (record 50276307) with original publication details: Bot. Mag. (Tokyo) 23: 229 1909.
This name was in version 1 of The Plant List, record tro-50276307, and has not been changed.