1	Style divided into a thin basal part and a thick upper part		(2)
+	Style uniformly thick, uniformly thin or tapering, not divided into 2 distinct parts		(4)
2 (1)	Style with thickened part (and keel) twisted through more than 360º, (stigma terminal but not penicillate), vexillum mostly without appendages		Phaseolus
+	Style with thickened part twisted through no more than 360º, usually up to 180º		(3)
3 (2)	Thickened part of the style abruptly curved through 90º just above its junction with the tenuous part, narrowed and slightly curved towards the apex, resembling a squarish hook		Macroptilium
+	Thickened part of the style not as above; style with a ribbon-like portion and variously curved, mostly with barbate thick part		Vigna
4 (1)	Style distinctly thickened, conspicuous; vexillum mostly purple, with distinct appendages near the base		Lablab
+	Style not distinctly thickened, often short and inconspicuous; vexillum with 2 long linear lamelliform appendages		Macrotyloma