1 | Corolla lobes in bud strongly twisted to the left, 1.8-9.5 times as long as wide |
1' | Corolla lobes in bud not strongly twisted, 0.9-1.8 times as long as wide |
2 | Leaves minutely punctate beneath |
2' | Leaves not minutely punctate beneath |
3 | Inflorescence mostly axillary, shorter than subtending leaves, often minutely puberulent |
3' | Inflorescence terminal panicles, usually longer than subtending leaves, glabrous |
4 | Corolla tube ≥ 5 mm long, lobes > 6 mm long; 7-11 strong pairs of secondary veins |
4' | Corolla tube < 5 mm long, lobes ≤ 5 mm long; 7-23 pairs of secondary veins, if ≤ 13 then only weakly distinct from tertiary venation |
5 | Inflorescence 1-3.7 cm long; disk 0.6-0.8 times as long as ovary; tube densely pubescent inside |
5' | Inflorescence 3.9-13.2 cm long; disk 0.3-0.6 times as long as ovary; tube glabrous or sparsely pubescent only at top inside |
6 | Inflorescence minutely puberulent, mostly axillary |
6' | Inflorescence glabrous, axillary or terminal |
7 | Inflorescence mostly axillary, if terminal not forming large panicles |
7' | Inflorescence terminal, sometimes also axillary, forming panicles |
8 | Leaves thickly coriaceous; petiole (1.5-)2-5.2 cm long; corolla lobes 1.7-2.9 mm long |
8' | Leaves coriaceous to subcoriaceous; petiole 0.5-2.1 cm long; corolla lobes 2.7-8.5 mm long |
9 | Inflorescence robust; leaves mostly narrow elliptic |
9' | Inflorescence delicate; leaves broad elliptic, oblong or obovate |
10 | Bracteoles on flower pedicels |
10' | Bracteoles at base of flower pedicels |
11 | Inflorescence delicate; anthers 1-1.3 by 0.3-0.4 mm. — Peninsular Thailand to Malesia |
11' | Inflorescence robust; anthers 1.1-4 by 0.4-0.8 mm. — Japan and China to Indochina and the Philippines |
12 | Corolla tube 4.7-8 mm long; leaf apex rounded to apiculate |
12' | Corolla tube 1.2-4.1(-4.7) mm long; leaf apex acuminate, very rarely to apiculate |
13 | Leaves glaucous beneath, secondary veins thin and not prominent |
13' | Leaves not glaucous beneath, secondary veins prominent or not |
14 | Corolla tube > 5 mm long; leaves 8-14 cm long |
14' | Corolla tube < 2 mm long; leaves 2.6-10.7 cm long |
15 | Inflorescence < 2 cm long; pedicels ≤ 1.2 mm long |
15' | Inflorescence > 3 cm long; pedicels ≥ 2 mm long |
16 | Leaf secondary veins arcuate ascending. — Ceram, Ambon |
16' | Leaf secondary veins ± straight, almost perpendicular to midrib. — Peninsular Malaysia, Borneo |