This name is a synonym of Echinopsis backebergii Werderm..
The record derives from Tropicos
(data supplied on 2012-04-18)
which reports it as a synonym (record 50321366) with original publication details: Kakteen And. Sukk. 17: 76 1966.
Full publication details for this name can be found in IPNI: http://ipni.org/urn:lsid:ipni.org:names:142739-2.
This name was in version 1 of The Plant List, record tro-50321366.