This name is a synonym of Rumex pseudonatronatus (Borbás) Murb..
The record derives from WCSP (in review)
(data supplied on 2012-03-23)
which reports it as a synonym with original publication details: Értek. Term. Köréb. Magyar Tud. Akad. 11(18): 21 1881.
Full publication details for this name can be found in IPNI: http://ipni.org/urn:lsid:ipni.org:names:60434379-2.
This name was in version 1 of The Plant List, record kew-2429963, and has not been changed.