This name is a synonym of Arrhenatherum longifolium (Thore) Dulac.
The record derives from WCSP
(data supplied on 2012-03-23)
which reports it as a synonym and as an illegitimate name (record 398039) with original publication details: Bot. Gall. ed. 2, 1: 514 1828.
This name was in version 1 of The Plant List, record kew-398039.