Key to the Lupinus hieronymi, L. burkartianus and L. austrorientalis Complex
1. Indumentum on stems and petioles with only one layer of erect and straight hairs 2.0–2.5 (–3.0) mm long, becoming golden brownish in herbarium specimens. Banner obovate ................................................................................................ 1. Lupinus hieronymi
- Indumentum on stems and petioles with two layers of hairs: one layer of semi-appressed to appressed hairs (0.9–) 1.3–1.5 (–2.0) mm long becoming yellowish-golden in herbarium specimens and with an undercoat of curly canescent 0.3–0.5 mm long hairs. Banner broadly obovate, orbicular, or wider than long......................................................................................................................2
2. Petiole 9.0–13.0 (–15.0) cm, about (2–) 2½–3 times the length of the leaflets. Stem and petiole indument with semi-appressed 1.3– 1.5 (–2.0) mm long hairs with an undercoat of curly 0.5 mm long hairs not totally covering the surface. Banner broadly obovate, (7.5–) 8.0–10.0 × 7.0– 9.5 mm. Keel angle more than 100º–120º ............................................................... 2. Lupinus burkartianus
- Petiole 5.0–9.0 cm, about 1½–2 times the length of the leaflets. Stem and petiole indumentum with appressed 0.9–1.3 mm long hairs with a dense undercoat of curly 0.3 mm long hairs, hiding the surface. Banner orbicular or wider than long (9–) 11–13 (–14) × 10–11–12(–13) mm. Keel angle 90º–95º ................................................................................................ 3. Lupinas austrorientalis