| | 1. Largest stipules 13–15 mm, widely elliptic to obtriangular; largest bracts 9–13 mm |
| R. hallii |
| | 1' Largest stipules 4–10 mm, ± elliptic, linear-lanceolate to -oblanceolate, or triangular; largest bracts 3–7 mm |
| |
| | 2. Calyx in flower 6–8 mm; banner 10–14 mm; fruit 4–7 mm, with an abrupt, small point at tip |
| R. physodes |
| | 2' Calyx in flower 9–10 mm; banner 14–15 mm; fruit 9–13 mm, with widely attached, < 3 mm beak |
| R. rigida
|