Click the number at the start of a key lead to highlight both that lead and its corresponding lead. Click again to show only the two highlighted leads. Click a third time to return to the full key with the selected leads still highlighted.
1 Fresh plants not aromatic when bruised; corolla predominantly white (in some species slightly pink or marked with yellow), 2-10 mm long; stem and leaves pubescent or glabrous.
..2 Leaves glabrous; leaf margins entire, finely and obscurely serrulate, or obviously crenate.
....3 Leaf blades typically with 5+ equally prominent nerves from the blade base; leaf margins obviously crenate; stems pubescent; pedicels 10-12 mm long
....3 Leaf blades with only the midvein readily apparent (any other veins distinctly fainter); leaf margins entire or finely and obscurely serrulate; stems glabrous; pedicels 5-30 mm long