| 1 | Leaf blade base rounded to cordate; sepal colleters present; corolla throat glabrous or with few hairs |
| 1' | Leaf blade base cuneate to obtuse, or rarely rounded; sepal colleters absent; corolla throat densely villous |
| 2 | 9-14 pairs of secondary veins but always with at least some leaves on the plant with > 9 pairs of secondary veins; never with tuft of hairs in secondary vein axils with midrib unless all of blade beneath pubescent; ovary densely to sparsely puberulent |
| 2' | 5-9(-11) pairs of secondary veins; often with tuft of hairs in secondary vein axils with midrib or all of blade beneath pubescent; ovary glabrous |
