This name is a synonym of Plantago australis subsp. sodiroana (Pilg.) Rahn.
The record derives from Tropicos
(data supplied on 2012-04-18)
which reports it as a synonym (record 25200512) with original publication details: Pflanzenr. 269: 236 1937.
Full publication details for this name can be found in IPNI: http://ipni.org/urn:lsid:ipni.org:names:201378-2.
This name was in version 1 of The Plant List, record tro-25200512.