This name is a synonym of Humularia kassneri var. vanderystii (De Wild.) P.A. Duvign..
The record derives from Tropicos
(data supplied on 2012-04-18)
which reports it as a synonym (record 13060688) with original publication details: Pl. Bequaert. 4(1): 58 1926.
This name was in version 1 of The Plant List, record tro-13060688, and has not been changed.