A genus of only three or four species of small trees and shrubs.  Previously if was included within the genus Sophora. The species of Styphnolobium differ from Sophora in lacking the ability to form symbioses with rhizobia (nitrogen fixing bacteria) on their roots. They also differ from the related genus Calia (mescal beans) in having deciduous leaves and flowers in axillary, not terminal, racemes. The leaves Styphnolobium are pinnate, with 9-21 leaflets, and the flowers in pendulous racemes similar to those of the Black locust.

Styphnolobium: Greek meaning dense, with lobos (pod, capsule).