This name is a synonym of Cymopterus hallii (A.Gray) B.L.Turner.
The record derives from Tropicos
(data supplied on 2012-04-18)
which reports it as a synonym (record 50233793) with original publication details: Proc. Amer. Acad. Arts 8: 288 1870.
Full publication details for this name can be found in IPNI: http://ipni.org/urn:lsid:ipni.org:names:327205-2.
This name was in version 1 of The Plant List, record tro-50233793, and has not been changed.