This name is a synonym of Amaranthus thunbergii Moq..
The record derives from WCSP (in review)
(data supplied on 2012-03-23)
which reports it as a synonym and as an illegitimate name with original publication details: Fl. Cap. ed. 2: 215 1823.
Full publication details for this name can be found in IPNI: http://ipni.org/urn:lsid:ipni.org:names:59386-1.
This name was in version 1 of The Plant List, record kew-2632651, and has not been changed.