This name is a synonym of Handroanthus obscurus (Bureau & K.Schum.) Mattos.
The record derives from iPlants
(data supplied on 2012-03-23)
which reports it as a synonym (record 319089) with original publication details: Mutisia 25: 16 1956.
Full publication details for this name can be found in IPNI: http://ipni.org/urn:lsid:ipni.org:names:248747-2.
This name was in version 1 of The Plant List, record kew-319089, and has not been changed.