This name is a synonym of Crotalaria pallidicaulis Harms.
The record derives from Tropicos
(data supplied on 2012-04-18)
which reports it as a synonym (record 13023127) with original publication details: Bothalia 2: 390 1928.
This name record (from Tropicos) was not included in version 1 of The Plant List. It is possible the same name was included from a different data source, to check this you can search for Crotalaria athroophylla in version 1 of The Plant List.