This name is a synonym of Helictochloa versicolor subsp. praetutiana (Arcang.) Romero Zarco.
The record derives from Tropicos
(data supplied on 2012-04-18)
which reports it as a synonym (record 25560011) with original publication details: Comp. Fl. Ital. 777 1882.
This name record (from Tropicos) was not included in version 1 of The Plant List. It is possible the same name was included from a different data source, to check this you can search for Avena scheuchzerii in version 1 of The Plant List.