This name is a synonym of Euphorbia nutans Lag..
The record derives from WCSP
(data supplied on 2012-03-23)
which reports it as a synonym (record 80218) with original publication details: Rep. U.S. Mex. Bound. 2(1): 188 1858.
Full publication details for this name can be found in IPNI: http://ipni.org/urn:lsid:ipni.org:names:101672-2.
This name was in version 1 of The Plant List, record kew-80218, and has not been changed.