This name is a synonym of Rumex crispus subsp. littoreus (Hardy) Akeroyd.
The record derives from WCSP (in review)
(data supplied on 2012-03-23)
which reports it as a synonym with original publication details: Rep. Bot. Exch. Club 1872-1874: 37 1875.
This name was in version 1 of The Plant List, record kew-2869536, and has not been changed.