This name is a synonym of Calystegia silvatica (Kit.) Griseb..
The record derives from Tropicos
(data supplied on 2012-04-18)
which reports it as a synonym (record 8502194) with original publication details: Syst. Veg. 4: 183 1819.
Full publication details for this name can be found in IPNI: http://ipni.org/urn:lsid:ipni.org:names:265709-1.
This name was in version 1 of The Plant List, record tro-8502194.