This name is a synonym of Euphorbia trialata (Huft) V.W.Steinm..
The record derives from WCSP
(data supplied on 2012-03-23)
which reports it as a synonym (record 273763) with original publication details: Contr. Univ. Michigan Herb. 20: 199 1995.
Full publication details for this name can be found in IPNI: http://ipni.org/urn:lsid:ipni.org:names:303821-2.
This name was in version 1 of The Plant List, record kew-273763, and has not been changed.