This name is a synonym of Ludwigia palustris (L.) Elliott.
The record derives from Tropicos
(data supplied on 2012-04-18)
which reports it as a synonym (record 23200191) with original publication details: Rhodora 37(437): 176 1935.
Full publication details for this name can be found in IPNI: http://ipni.org/urn:lsid:ipni.org:names:144393-2.
This name was in version 1 of The Plant List, record tro-23200191.