This name is a synonym of Ammannia robusta Heer & Regel.
The record derives from WCSP (in review)
(data supplied on 2012-03-23)
which reports it as a synonym with original publication details: Sci. Stud. Montana Coll. Agric., Bot. 1: 87 1905.
Full publication details for this name can be found in IPNI: http://ipni.org/urn:lsid:ipni.org:names:11323-2.
This name was in version 1 of The Plant List, record kew-2633641, and has not been changed.