This name is a synonym of Plantago triandra subsp. masoniae (Cheeseman) Sykes.
The record derives from Tropicos
(data supplied on 2012-04-18)
which reports it as a synonym (record 50258220) with original publication details: Trans. & Proc. New Zealand Inst. 53: 424 1921.
Full publication details for this name can be found in IPNI: http://ipni.org/urn:lsid:ipni.org:names:685400-1.
This name was in version 1 of The Plant List, record tro-50258220.