This name is a synonym of Plantago barbata subsp. monanthos Rahn.
The record derives from Tropicos
(data supplied on 2012-04-18)
which reports it as a synonym (record 25200282) with original publication details: Bot. Jahrb. Syst. 50(Suppl.): 64 1914.
Full publication details for this name can be found in IPNI: http://ipni.org/urn:lsid:ipni.org:names:201229-2.
This name was in version 1 of The Plant List, record tro-25200282, and has not been changed.