A new form of a rare Mexican species, selected and named here for its foliage effect. This is potentially a medium to large densely branched shrub, clothed to the ground with darker-green, shinier foliage than is usual, with slimmer, undulate, spiny leaflets. Short, dense racemes of sweetly fragrant vivid-yellow flowers in spring. Hardy. Sun or semi-shade in most soils. Originally collected in southern Mexico at approx' 2200m asl.