This name is a synonym of Stipagrostis uniplumis (Licht.) De Winter.
The record derives from WCSP
(data supplied on 2012-03-23)
which reports it as a synonym (record 465280) with original publication details: Mém. Acad. Sci. Inst. France 62: 7 1935.
This name record (from WCSP) 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 Aristida pogonoptila in version 1 of The Plant List.