M. amplifolia (Mappa)

M. loheri (Javanica)

M. auctoris ( ? )

M. lowii (Pseudorottlera)

M. balabacensis (Longistipulata)

M. mappa (Mappa)

M. bancana (Pachystemon)

M. noblei (Mappa)

M. bicolor (Bicolor)

M. ovatifollia (Mappa)

M. congestiflora (Bicolor)

M. sinensis (Javanica)

M. cumingii (Javanica)

M. stonei ( ? )

M. grandifolia (Mappa)

M. sylvatica (Javanica)

M. hispida (Longstipulata)

M. tanarius var. tanarius (Tanarius)

M. leytensis (Mappa)

M. tanarius var. tomentosa (Tanarius)

1a.

Twig with an apparently single, erect, conspicuous, irritantly hairy stipule

2

1b.

Stipules 2, sometimes soon caducous

3

2a.

Leaves not peltate, strongly cordate at the base, sometimes with a few large inconspicuous basal glands. Staminate bracteoles linear-elliptic, 3 mm, caducous. Common

74. M. hispida

2b.

Leaves peltate, shallowly cordate or truncate, with several large glands near petiole insertion. Staminate bracteoles ovate-elliptic, 7 mm, with deep narrow glandular teeth, persistent. Once collected, Mindoro

19. M. balabacensis

3a.

Leaves at least 3 cm peltate

4

3b.

Leaves not or only to 15 mm peltate

11

4a.

Leaves huge, 40 cm or more long, base sometimes broadly rounded

5

4b.

Leaves not over 20 (once 26) cm long, base truncate

7

5a.

Leaves drying grey, paler below. Staminate inflorescences congested panicles; bracteoles fimbriate

17. M. auctoris

5b.

Otherwise. Leaves drying brown

6

6a.

Leaves 60 by 40 cm, with white tufted hairs below, petiole 50 cm. Staminate inflorescences furfuraceous panicles to 50 cm, main axis stout angular, others flattened;basal peduncle 6(–28) cm; main axis bracts soon caducous; bracteoles crenate.  Infructescence a raceme.  Fruits 10 mm, unarmed

104. M. mappa

6b.

Leaves 40 by 35 cm, hairs if present not tufted, petiole 35 cm.  Staminate inflorescences glabrous dense panicles to 20 cm, with all axes flattened and conspicuous bracts, to 4 by 1 cm on main axis; basal peduncle 5 cm; bracteoles entire.  Infructescence a spherical axillary 6c m mass of 6 mm fruits bearing 1 cm tentacular processes

67. M. grandifolia

7a.

At least some leaves trilobed or cusped

8

7b.

Leaves not lobed or cusped

9

8a.

Twigs hollow ant-inhabited.  Stipules persistent, recurved, slightly leathery.  Leaves usually trilobed.  Staminate bracteoles entire.  Inflorescences expanded racemes.  Collected twice

20. M. bancana

8b.

Twigs solid.  Stipules soon caducous.  Leaves mostly very shallowly lobed.  Staminate bracteoles fimbriate.  Inflorescences small congested racemes. Palawan

40. M. congestiflora

9a.

Leaves drying bicoloured, grey and brown.  Stipules soon caducous.  Bracteoles 2 mm, entire or shallowly dentate.  Fruits unarmed

24. M. bicolor

9b.

Leaves otherwise.  Stipules persistent, broadly elliptic, 8–20 mm long. Bracteoles 5–12 mm long, deeply toothed.  Fruits with slender processes on upper half

10

10a.

Twigs and stipules glabrous. Petioles and leaves pubescent but very soon becoming glabrous. Staminate inflorescences including bracteoles glabrous. Staminate bracteoles not exceeding 6 by 3 mm. Fruits glabrous

163. M. tanarius var. tanarius

10b.

Twigs and stipules finely pubescent or furfuraceous (sometimes becoming glabrous). Petioles, leaves and staminate inflorescences  including bracteoles furfuraceous to finely pubescent. Staminate bracteoles sometimes 12 by 13 mm. Fruits granular glandular

163. M. tanarius var. tomentosa

11a.

Leaves below without granular glands

94. M. leytensis

11b.

Leaves below with granular glands

12

12a.

Leaves ovate, 20 by 17 cm, base strongly cordate, apex acute, glabrous.  Twigs glabrous.  Pistillate panicle 8 cm, narrow. Fruits monococcous, pedicel under 1mm.  (Staminate unknown)

114. M. ovatifolia

12b.

Leaves deltoid, base cuneate or truncate, rarely shallowly cordate, weakly peltate or not

13

13a.

Leaves with tufted white hairs on both surfaces, velvety below.  Fruiting pedicel 4–5 mm

111. M. noblei

13b.

Not so

14

14a.

Stipules whisker-like, persistent

100. M. lowii

14b.

Stipules otherwise, usually soon caducous

15

15a.

Twigs stout, c. 1 cm diam., rufous velvety glabrescent. Stipules elliptic,  45 by 5 mm, apex acuminate. Leaves deltoid, 17-35 by 9-20 cm. Staminate panicles crowded, amongst leaves; bracteoles tiny, 2 by 1 mm, persistent. Fruits dicoccous, pedicel 2 mm

10. M. amplifolia

15b.

Otherwise

16

16a.

Twigs slender, 3 mm diam., slightly angled, glabrous. Stipules oblong–elliptic, 20 by 4 mm glabrous, recurved, subpersistent. Staminate bracteoles 5 mm, spoonlike, spreading

155. M. stonei

16b.

Otherwise (M. javanica group)

17

17a.

Leaves ovate, thinly leathery, base very broadly truncate, margin crenate, apex acute to acuminate, secondary nerves very straight. Stipules glabrous. Inflorescence axes glabrous.  Bracteoles linear, 3 mm, broadening to 1–2 patellar glands at tip, mostly soon caducous

150. M. sinensis

17b.

Leaves elliptic to ovate, base truncate to cuneate, margin rarely crenate, leathery or papery.  Bracteoles otherwise

18

18a.

Bracteoles conspicuous, persistent, spreading, ovate, 10 by 1.5 mm, tapering to base, with 2–3 big adaxial patellar glands.  Inflorescence axes glabrous. Stipules glabrous. (Pistillate unknown)

96. M. loheri

18b.

Bracteoles inconspicuous or soon caducous, tiny, usually 1–2 mm, smaller than flower clusters.  Inflorescence axes at first furfuraceous.  Stipules finely furfuraceous

19

19a.

Bracteoles mostly soon caducous, variable, ovate, 1–3(–7) mm, apex acute to acuminate, with 2–4 big adaxial glands, glabrous.  Fruiting pedicel very long, 2–3 cm, fruits clustered 2–3(–5), mostly towards tip of infructescence; stigmas a tiny plate, slightly eccentric.  Leaves sometimes caudate, secondary nerves c. 7 pairs

46. M. cumingii

19b.

Bracteoles persistent, ovate, tiny, under 1–2 mm, glandless, furfuraceous.  Fruiting pedicel 2–5 mm; fruits solitary or to 4; styles long, thread-like, caducous. Leaves acuminate, secondary nerves c. 12 pairs. Staminate inflorescences often very dense tangles

162. M. sylvatica