This name is a synonym of Magnolia ptaritepuiana Steyerm..
The record derives from WCSP
(data supplied on 2012-03-23)
which reports it as a synonym (record 117802) with original publication details: Fieldiana, Bot. 28(1): 234 1951.
Full publication details for this name can be found in IPNI: http://ipni.org/urn:lsid:ipni.org:names:149309-2.
This name was in version 1 of The Plant List, record kew-117802, and has not been changed.