This name is a synonym of Arundinella hirta .
The record derives from WCSP
(data supplied on )
which reports it as a synonym (record 450705
) with original publication details: Acta Phytotax. Geobot. 57: 71 2006.
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 Arundinella riparia in version 1 of The Plant List.