| 1 | Low shrub; leaves suborbicular, 0.8-1.2 cm wide, 3-veined; inflorescence a dense panicle, 1-3 cm long |
| 1' | Slender herb; leaves linear to narrowly elliptic, 0.03-0.3 cm wide, venation hardly visible; inflorescence a loose repeatedly branched dichasium, up to 10 cm long |
| 2 | Flowers homostylous, corolla tube cylindrical often slightly narrowed in upper part, anthers connective not prolonged above thecae |
| 2' | Flowers heterostylous, corolla tube infundibuliform, anthers connective prolonged above thecae |
