This name is a synonym of Bromus hordeaceus subsp. thominei (Hardouin) Maire.
The record derives from WCSP
(data supplied on 2012-03-23)
which reports it as a synonym (record 401180) with original publication details: Syn. Deut. Schweiz. Fl. ed. 3, 3: 2784 1907.
This name was in version 1 of The Plant List, record kew-401180.