This name is a synonym of Aristida laevis (Nees) Kunth.
The record derives from WCSP
(data supplied on 2012-03-23)
which reports it as a synonym (record 394324) with original publication details: Anales Mus. Nac. Buenos Aires 11: 88 1904.
This name was in version 1 of The Plant List, record kew-394324, and has not been changed.