| 1 |
Inflorescences 2- or 3-branched |
|
(2) |
| + |
Inflorescences usually not branched |
|
(4) |
| |
|
|
|
| 2 (1) |
Leaf blade 3-7 × 1.5-3.5 cm; inflorescences less than 5 × 3 cm; plants less than 50 cm tall. |
|
3 P. hainanensis |
| + |
Leaf blade 8.5-16 × 4.7-10.5 cm; inflorescences 8-10 × ca. 4 cm or ca. 4 × 4 cm; plants 30-100 cm tall |
|
(3) |
| |
|
|
|
| 3 (2) |
Leaf blade abaxially densely white bullate, margin entire; branchlets puberulous. |
|
1 P. erecta |
| + |
Leaf blade abaxially puberulous and sparsely strigose, margin inconspicuously denticulate; branchlets densely puberulous and with sparse glandular trichomes. |
|
2 P. cymigera |
| |
|
|
|
| 4 (1) |
Peduncle 4-24 cm |
|
(5) |
| + |
Peduncle less than 4 cm |
|
(9) |
| |
|
|
|
| 5 (4) |
Leaf blade adaxially usually with a line of whitish yellow spots between secondary veins. |
|
19 P. scorpiothyrsoides |
| + |
Leaf blade adaxially without whitish yellow spots between secondary veins |
|
(6) |
| |
|
|
|
| 6 (5) |
Fertile stamens 4 plus 4 staminodes or staminodes lacking |
|
(7) |
| + |
Fertile stamens 8, equal or subequal in length |
|
(8) |
| |
|
|
|
| 7 (6) |
Stamens 4, staminodes absent; calyx furfuraceous puberulous; leaf blades elliptic, ovate, or rarely suborbicular, both surfaces furfuraceous puberulous. |
|
20 P. tetrandra |
| + |
Fertile stamens 4 plus 4 staminodes; calyx furfuraceous and with sparse glandular trichomes; leaf blades elliptic to suborbicular, rarely obovate, adaxially sparsely short setose. |
|
21 P. elattandra |
| |
|
|
|
| 8 (6) |
Petiole hirsute or tomentose; leaf blades strigose; stamens subequal in length. |
|
22 P. cavaleriei |
| + |
Petiole puberulous, glabrescent; leaf blades puberulous; stamens equal in length. |
|
23 P. asarifolia |
| |
|
|
|
| 9 (4) |
Leaf blade base cordate to shallowly cordate or if rounded or obtuse then branchlets puberulous |
|
(10) |
| + |
Leaf blade base cuneate to obtuse or if rounded-subcordate then branchlets appressed setose or hirsute |
|
(15) |
| |
|
|
|
| 10 (9) |
Hypanthium with glandular trichomes or glandular puberulous |
|
(11) |
| + |
Hypanthium setose or puberulous and villous |
|
(12) |
| |
|
|
|
| 11 (10) |
Flower 3-merous; calyx only with glandular trichomes; anther connective decurrent into a short non-tuberculate spur. |
|
13 P. ternata |
| + |
Flower 4-merous; calyx puberulous and with glandular trichomes; anther connective decurrent into a short tuberculate spur. |
|
14 P. velutina |
| |
|
|
|
| 12 (10) |
Hypanthium puberulous; calyx lobes shorter than 1 mm. |
|
15 P. gracilis |
| + |
Hypanthium setose or puberulous and villous; calyx lobes greater than 1 mm |
|
(13) |
| |
|
|
|
| 13 (12) |
Leaf blade 11-23 × 7-13 cm, abaxially densely furfuraceous and puberulous, adaxially densely furfuraceous and sparsely strigose. |
|
16 P. longiradiosa |
| + |
Leaf blade 3.5-7.5 × 1.5-4 cm, abaxially densely pustulate or only puberulous on veins, adaxially puberulous and strigose |
|
(14) |
| |
|
|
|
| 14 (13) |
Leaves with 2 secondary veins on each side of midvein. |
|
17 P. longearistata |
| + |
Leaves with 3 secondary veins on each side of midvein. |
|
18 P. latisepala |
| |
|
|
|
| 15 (9) |
Branchlets glabrous or puberulous and with sparse glandular trichomes |
|
(16) |
| + |
Branchlets densely setose, villous, or retrorse setose |
|
(19) |
| |
|
|
|
| 16 (15) |
Peduncle 2.5-6 cm. |
|
11 P. oligotricha |
| + |
Peduncle less than 1 cm or nearly absent |
|
(17) |
| |
|
|
|
| 17 (16) |
Leaf blades 10-17(-20) × 3-7(-8) cm, both surfaces densely bullate. |
|
4 P. setotheca |
| + |
Leaf blades 5-10(-12.5) × 1-2.3(-6.5) cm, both surfaces smooth |
|
(18) |
| |
|
|
|
| 18 (17) |
Leaf blades 1-2.3 cm wide, both surfaces glabrous; secondary veins 1 on each side of midvein. |
|
5 P. stenophylla |
| + |
Leaf blades 3-6.5 cm wide, both surfaces puberulous; secondary veins 2 or 3 on each side of midvein. |
|
6 P. plagiopetala |
| |
|
|
|
| 19 (15) |
Branchlets and hypanthium densely appressed setose or branchlets retrorse setose and hypanthium puberulous and with glandular trichomes |
|
(20) |
| + |
Branchlets hirsute or villous, hypanthium densely stellate pilose, puberulous, and sparsely hispid or with dense glandular trichomes |
|
(22) |
| |
|
|
|
| 20 (19) |
Petals ca. 1.4 cm; anther connective abaxially tuberculate; leaf blade base cuneate. |
|
7 P. melastomatoides |
| + |
Petals 0.8-1 cm; anther connective not tuberculate; leaf blade base rounded or slightly cordate |
|
(21) |
| |
|
|
|
| 21 (20) |
Branchlets obtusely 4-sided, appressed densely setose. |
|
8 P. fengii |
| + |
Branchlets terete, with stout brownish or white bristles to 1.5 cm at nodes, glabrous when old. |
|
24 P. tentaculifera |
| |
|
|
|
| 22 (19) |
Hypanthium with glandular trichomes; leaf blade 5-13 × 1.5-4 cm. |
|
12 P. deltoidea |
| + |
Hypanthium with stellate trichomes or puberulous and sparsely hirsute; leaf blade 7-18 × 3-8.5 cm |
|
(23) |
| |
|
|
|
| 23 (22) |
Hypanthium with 8-12 mm whitish trichomes. |
|
9 P. hispidissima |
| + |
Hypanthium puberulous and sparsely hirsute. |
|
10 P. ovalifolia |
