This name is a synonym of Mimulus floribundus var. membranaceus (A. Nelson) A.L. Grant.
The record derives from Tropicos
(data supplied on 2012-04-18)
which reports it as a synonym (record 50102144) with original publication details: Bot. Gaz. 34(1): 30–31 1902.
Full publication details for this name can be found in IPNI: http://ipni.org/urn:lsid:ipni.org:names:162287-2.
This name was in version 1 of The Plant List, record tro-50102144, and has not been changed.