Flora of Thailand

 

Euphorbiaceae

 

Key to the Euphorbiaceae genera of Thailand

 

Peter C. van Welzen

 

The key is regularly updated. Therefore, comments from users are very welcome (click on the author's name and after that on the email address). The key can also be used for identifying most West Malesian genera.

The key is an improved version of the one published in the Malesian Euphorbiaceae Newsletter 8.

 

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Concise key to the Major Groupings

Key to the Genera

 

Concise key to the Major Groupings

 

This key provides a short-cut to the large groups recognised in the main key. It helps to move quickly to the desired group. The questions are similar to those of the main key.

 

1a.

Plants deciduous, flowering and/or fruiting while leafless

Question 2 of main key

1b.

Plants deciduous or not, flowering and/or fruiting while (just) in leaf

2

2a.

Leaves palmate (divided into leaflets) or palmatifid to at least the upper third of the lamina; basal nerves palmate, supporting lobes or leaflets

Question 6 of main key

2b.

Lamina not palmate or palmatifid to more than the upper third; nerves usually pinnate (to palmate)

3

3a.

Plants lianas (or prostrate or twining herbs/shrubs) with stinging hairs. Glandular scales lacking

Question 16 of main key

3b.

Herbs, shrubs or trees, seldom liana-like. Stinging hairs absent except sometimes on fruits (Chaetocarpus); glandular scales present or absent

4

4a.

Flowers in cyathia. Plant creeping herbs, erect herbs, small shrubs, or often succulent and even cactus-like. Rich in white latex

Question 22 of main key

4b.

Flowers never in cyathia, usually separate, sometimes in dense heads, but then heads not surrounded by calyx-like and glandular bracts. Plants herbs, shrubs or trees. Succulent stem usually absent (Falconeria is an exception), thorn-shaped stipules, and cyathia absent. Latex or absent

5

5a.

Leaves all opposite

Question 24 of main key

5b.

Leaves alternate, in pseudo-whorls or partly, but never all, opposite

6

6a.

Leaves and/or inflorescences with stellate hairs, lepidote hairs, glandular scales and/or scale hairs (use microscope or hand lens!)

Question 34 of main key

6b.

Leaves and/or inflorescences hairless or with simple hairs only

7

7a.

Inflorescences opposite to the leaves (sympodial growth). Leaves with translucent dots (hold leaves against light)

82. Suregada

7b.

Inflorescences terminal, axillary, or rami- to cauliflorous, usually not opposite, if opposite then leaves not punctate

8

8a.

Flowers and fruits single per leaf axil or in axillary fascicles (no inflorescence axis present); fruits without rows of short spines

Question 58 of main key

8b.

Flowers and fruits in racemes, spikes or panicles; fruits with or without rows of short spines

9

9a.

Leaves with 2 glands near or at blade insertion; these in various positions, either:

- petiole with 2 sub-apical glands or

- leaes on upper or lower side with basally either 2 raised glands at insertion or

- with (1)2(more) sub-basal submarginal glandular areas (black areas), or

- leaves with two sub-basal glands in margin

Question 87 of main key

9b.

Leaves without basal glands at insertion, or glandular, subbasal areas, or subbasal glands in margin

10

10a.

Sepals 2, broad lobes in all flowers. Petals absent. Ovary 2-locular. Fruits leathery berries

Question 109 of main key

10b.

Sepals 2-5, when 2 sepals then petals present. Petals absent or present. Fruits drupaceous, berry-like or capsular

11

11a.

Axillary buds above each other (check especially older branches). Stipules not on internode, but above or below leaves, check scars on older branches! Leaves (narrowly) elliptic to obovate, long. Inflorescences with very broad, convex bracts, covering flowers, caducous. Flowers with petals

3. Agrostistachys

11b.

Axillary buds usually only visible, at most in circular groups. Stipules absent or when present next to leaf petiole on node. Leaves ovate to obovate, short to long. Inflorescences without broad bracts. Flowers with or without petals

12

12a.

Leaves with entire (or somewhat wavy) margin, sometimes lobed. Be careful, use hand lens or microscope when not sure, if small glands are protruding then use the other lead!

Question 112 of main key

12b.

Leaves with crenate, serrate or dentate margins (N.B. sometimes only small, glandular teeth protruding)

Question 143 of main key

 

Key to the Genera

 

This key is very long and elaborate, and often difficult (a microscope or handlens is a prerequisite). There are two reasons for this, the former key by Airy Shaw (Kew Bull. 26: 194-203. 1972) often neglected exceptions and complete material (staminate flowers, pistillate flowers, fruits and seeds) was needed. The present key should accommodate (most) exceptions and usually has separate entries for staminate and pistillate flowers or fruits.

 

1a.

Plants deciduous, flowering and fruiting while leafless

2

1b.

Plants deciduous or not, flowering and fruiting while (just) in leaf

5

2a.

Cactus-like tree-shrubs. White latex present

38. Euphorbia

2b.

Shrubs to trees, not cactus-like. White latex present or abstent

3

3a.

Shrubs (usually several unbranched branches together). Flowers in zygomorphic cyathia (condensed heads), upturned bract with a scale-like nectary inside at its base, other bracts without. Cultivated

71. Pedilanthus

3b.

Shrubs to trees. Flowers in racemes or thyrses. Bracts in inflorescence with big glands or without

4

4a.

Branchlets slender (normal), hard, not spongy, not shrivelling when dry. Bracts in inflorescence without glands. Petals present at least in staminate flowers. Stamens numerous. Sepals 5. Latex colourless or red

30. Croton

4b.

Branchlets thick, soft, spongy, shrivelled when dry. Bracts in inflorescence with big glands. Petals always absent. Stamens 2. Calyx 2- or 3-lobed. Latex white

40. Falconeria

5a.

Leaves palmate divided into leaflets) or palmatifid for at least the upper third of the lamina; basal nerves palmate, supporting lobes or leaflets.

6

5b.

Lamina not palmate or palmatifid for more than the upper third; nerves usually pinnate (to palmate).

15

6a.

Leaves 3-foliolate, leaflets completely free

7

6b.

Leaves palmatifid, leaflets at least basally united (39 nerves)

9

7a.

Leaflet margin entire to wavy. Sepals united into a calyx. Fruits capsular (dehiscent), up to 5 cm long. Inflorescences without large, showy bracts

46. Hevea

7b.

Leaflet margin serrate. Sepals free. Fruits up to 1 cm long, either drupaceous (indehiscent) or capsular, but then inflorescence with large showy bracts

8

8a.

Latex red. Trees, dioecious; with normal, non-stinging hairs. Inflorescences without large showy bracts around flowers. Stamens free. Fruits drupaceous

12. Bischofia

8b.

Latex indistinct. Erect or twining herbs; with stinging hairs. Inflorescences with large showy bracts around flowers. Filaments united. Fruits capsular

31. Dalechampia (elongata)

9a.

Leaf margins entire or serrate (sometimes only vein endings extruding); if entire then leaves peltate

10

9b.

Leaf margins entire; leaves not peltate

13

10a.

Climbers. Inflorescences capitate, enveloped by 2 large membranous bracts

31. Dalechampia (bidentata)

10b.

Shrubs or trees. Inflorescences not capitate, never enveloped by large bracts

11

11a.

Leaves with 7 or 9 lobes. Stipule opposite leaf, encircling stem. Stamens united in branching groups

76. Ricinus

11b.

Leaves with 2, 3 or 5 lobes. Stipules beside petiole base, not united, not encircling stem. Stamens not branching

12

12a.

Leaves never peltate, lacking glandular scales. Inflorescences usually bisexual, monoecious. Sepals imbricate. Disc (lobes) present. Fruits never spiny, 3-locular

11. Baliospermum

12b.

Leaves often peltate, with glandular scales underneath. Inflorescences unisexual, dioecious. Sepals valvate (touching). Disc absent. Fruits often armed, 1-3-locular

55. Macaranga

13a.

Leaf base/end of petiole with 2 raised glands. Petals more than 1 cm long

87. Vernicia

13b.

Leaf base without raised glands. Petals absent or less than 1 cm long

14

14a.

Leaves divided to two-thirds only, either peltate (> 2 mm) and without glandular hairs or basally attached and with glandular hairs

51. Jatropha

14b.

Leaves almost completely divided, basally attached or slightly (2 mm) peltate, without glandular hairs. Usually cultivated for edible roots

57. Manihot

15a.

Plants lianas (or prostrate or twining herbs/shrubs) with stinging hairs (check especially the calices and/or lower leaf surface and/or inflorescences). Glandular scales lacking (Mallotus repandus and Croton caudatus are climbers but lack stinging hairs)

16

15b.

Herbs, shrubs or trees, seldom liana-like. Stinging hairs absent except sometimes on fruits (Chaetocarpus); glandular scales present or absent

21

16a.

Inflorescences capitate, enveloped by 2 large membranous bracts

31. Dalechampia (falcata)

16b.

Inflorescences spikes, panicles or cymes, sometimes with large bracts at end of inflorescence (thus not enveloping inflorescence)

17

17a.

Leaves coriaceous. Inflorescences with more than 2 cm long floral bracts at end of inflorescence. Stamens connate

66. Omphalea

17b.

Leaves papery. Inflorescences with short, less than 1 cm long floral bracts. Stamens free

18

18a.

Leaf base with 2 raised glands on upper surface. Stamens 8-13. Capsule 4-locular, winged or horned

74. Plukenetia

18b.

Leaf base without apically raised glands on upper surface. Stamens 2 or 3. Capsule 3-locular, without wings or horns

19

19a.

Inflorescences terminal, but sometimes on leafless side-branches and appearing laterally. Staminate calyx 4- or 5-lobed; stamens 2, subsessile, filaments slender, connective not thickened, nor elongated above thecae. Pistillate calyx lobes ca. 2 mm long

68. Pachystylidium

19b.

Inflorescences axillary or leaf-opposed. Staminate calyx 3-lobed; stamens 3, filaments thickened, connective thick, appendaged above thecae. Pistillate calyx lobes more than 2 mm long, especially in fruit

20

20a.

Leaf blades ovate and basally cordate to obovate with a narrow cordate base, widest above leaf insertion. Pistillate calyx with 3 lobes, less than 1 cm long in fruit; styles free, stigmas papillate, persistent

27. Cnesmone

20b.

Leaf blades broadly cordate, widest at leaf insertion. Pistillate calyx with 6 lobes, more than 1 cm long in fruit; styles connate with a clavate, non-papillate stigma, not persistent

59. Megistostigma

21a.

Flowers in cyathia (flowers contracted into dense heads with minute staminate flowers outside the pistillate flower, surrounded by calyx-like and glandular bracts, sometimes even upper leaves red-coloured). Plants creeping herbs, erect herbs, small shrubs, or often succulent and even cactus-like. Rich in white latex

22

21b.

Flowers never in cyathia, usually separate, sometimes in dense heads, but then heads not surrounded by calyx-like and glandular bracts. Plants herbs, shrubs or trees. Succulent stem usually absent (Falconeria somewhat exceptional), thorn-shaped stipules, and cyathia absent. Latex present or absent

23

22a.

Cyathia actinomorphic, spreading, nectary scales surrounding flowers. Leaves opposite or alternate. Native or cultivated, creeping herbs to succulent tree-shrubs, sometimes cactus-like, usually not deciduous

38. Euphorbia

22b.

Cyathia zygomorphic, shoe- or boat-shaped bracts enveloping flowers, upturned bract with scale-like, large and small nectaries inside at its base. Leaves alternate. Cultivated shrublet, leaves often variegated white-green, stem succulent, not cactus-like, deciduous

71. Pedilanthus

23a.

Leaves all opposite (one of each pair may be stipule-like and caducous, then inflorescence opposite leaf and longer than 1 cm)

24

23b.

Leaves alternate, in pseudo-whorls or partly but never all, opposite (Suregada with leaf-opposed, up to 1 cm long inflorescences)

33

24a.

Lower leaf surfaces and/or inflorescences with stellate hairs and/or glandular scales (microscope or hand lens!, sometimes only along the basal margin!; check especially young parts)

56. Mallotus

24b.

Leaves and inflorescences glabrous or with simple hairs

25

25a.

Opposite leaf stipule-like (inflorescences opposite normal leaf)

45. Hancea

25b.

Leaves of each pair equal in size and shape

26

26a.

Leaf margin entire

27

26b.

Leaf margin serrate

29

27a.

Stamens in dichotomously branching groups. Ovary and fruit with spined tubercles

53. Lasiococca

27b.

Stamens free, not branching. Ovary and fruit smooth, without tubercles

28

28a.

Flowers single per axil, petals present. Pistillate sepals more than 3 mm, often enlarging in fruit. Fruits about as wide as long

2. Actephila

28b.

Flowers in axillary groups (very short panicles), petals absent. Pistillate sepals up to 2 mm long, not enlarging in fruit. Fruits longer than wide

8. Austrobuxus

29a.

Herb. Leaves with basal glands. Northern, Doi Inthanon

61. Mercurialis

29b.

(Shrubs or) trees. Leaves with or without basal glands

30

30a.

Leaf base asymmetric, oblique, cordate. Stipules interpetiolary (like Rubiaceae, 1 per leaf, in between leaf pairs).  Petiole usually red. Staminate flowers on long thin pedicels united in catkins; below every catkin one pistillate flower with small leaf-like sepals

37. Erismanthus

30b.

Leaf base symmetric to slightly asymmetric, cordate to acute. Stipules petiolary (2 per petiole, thus 4 per leaf pair)

31

31a.

Leaves usually with basal glands on upper surface. Stamens 35 or more. Pistillate flowers single, on long pedicel (3-9 cm long), with long stigmas (8-14 mm)

25. Cleidion

31b.

Leaves without basal glands on upper surface. Stamens 3 or 8. Pistillate flowers in groups or on inflorescences with staminate flowers, on much shorter pedicels (less than 3 cm), stigmas less than 8 mm long

32

32a.

Latex absent. Hairs present at least on fruits. Leaves with or without stipellae at apex of petiole; when without stipellae then macular glands on upper leaf surface present. Stamens 8, joined at base. Pistillate sepals (3)4-8

4. Alchornea

32b.

Latex white. Plants completely glabrous. Leaves without stipellae and without macular glands. Stamens 3, free. Pistillate sepals 3

39. Excoecaria

33a.

Leaves and/or inflorescences with stellate hairs, lepidote hairs, glandular scales and/or scale hairs (microscope or hand lens!)

34

33b.

Leaves and/or inflorescences glabrous or with simple hairs only

56

34a.

Lower leaf surface and/or inflorescences with glandular scales (whitish to yellowish, orangish or reddish dots), sometimes hidden by dense stellate hairs

35

34b.

Leaves and/or inflorescences lacking glandular scales, only stellate, lepidote or scale hairs present

38

35a.

Inflorescences opposite to leaves. Petals with apical gland(s). Stamens with apical gland on connective

69. Pantadenia

35b.

Inflorescences terminal or in axils of leaves. Petals absent. Stamens without apical gland on connective

36

36a.

Staminate flowers in dense catkins (main axis not visible). Calyx papery, cupular, 5-teethed. Stamens 5, on sepals (episepalous). Ovary 2-locular. Fruit a capsule of 2 flat, somewhat roundish wings, unarmed

50. Hymenocardia

36b.

Staminate flowers in racemes, spikes or panicles (main axis clearly visible). Sepals free, not papery but thicker, 3 or 4 lobes. Stamens 1250, on receptacle. Ovary 2-5-locular. Fruit a non-flattened capsule, often spiny

37

37a.

Stamens 1-20, anthers (3)4-celled. Stellate hairs absent. Stem hollow or solid. Inflorescences often axillary only

55. Macaranga

37b.

Stamens 15-250, anthers 2-celled. Stellate hairs always present (sometimes few) on lower leaf surface and/or inflorescences (microscope or hand lens!). Stems solid. Inflorescences mainly terminal

56. Mallotus

38a.

Leaf margins entire, though often wavy or irregular

39

38b.

Leaf margins dentate or serrate (N.B. the teeth may be minute and just be protruding nerve ends)

50

39a.

Woody herbs to herb-like shrubs to small trees. Leaves white hairy below, about as broad as wide, lobed or with rim along petiole (somewhat subpeltate)

40

39b.

Shrubs to trees. Leaves not white hairy below or when white hairy then much longer than wide, not lobed, peltate or not

41

40a.

Leaves usually lobed, with flat margin along petiole; lower surface usually with few big glands near point of insertion only. Stamens 13-16. Pistillate flowers with sepal-like petals (5 sepals + 5 petals)

21. Chrozophora

40b.

Leaves not lobed, base of blade with a rim along the petiole; lower surface with yellow glands spread over leaf, not near point of insertion. Stamens 40-60. Pistillate flowers without petals

84. Thyrsanthera

41a.

Inflorescences panicles, with very long branches. Fruits large, more than 4 cm long, drupaceous. Cultivated tree

5. Aleurites

41b.

Inflorescences racemes, heads, spikes or spike-like panicles (without long side branches, though sometimes pistillate flowers with long stalks or staminate flowers in pedicelled groups along rachis). Fruits usually small, less than 2 cm high, when larger then capsular

42

42a.

Flowers in dense heads, many staminate, one or few pistillate. Leaves (sub)glabrous (long and narrow). Filaments united into a tube, fleshy, 4 or 5. Stigmas flat, broad, much branched to fimbriate

52. Koilodepas

42b.

Flowers in racemes or spikes, uni- or bisexual. Leaves (sub)glabrous to usually hairy, at least below. Filaments free or connate, when connate then 6-10 stamens. Stigmas not broadened and flattened

43

43a.

Leaf blades peltate for at least 2 mm

44

43b.

Leaf blades not peltate, basally attached

46

44a.

Leaves with at least 2 raised glands near apex of petiole, without macular glands on lower blade surface

35. Endospermum

44b.

Leaves without glands on petiole, but with rows of macular glands on lower blade surface

45

45a.

Leaf blades only peltate for ca. 2 mm, peltation sticking forwards. Indumentum of lepidote hairs. (Not a Croton, but material insufficient for correct generic placement. See at end of genus treatment for description)

30. Croton santisukii

45b.

Leaf blades for more than 5 mm peltate, peltation flat. Indumentum stellate hairs

81. Sumbaviopsis

46a.

Leaves always with 2 glands near point of petiole insertion, on upper or lower surface, sometimes indistinct. Hairs stellate, lepidote or scale-like. Inflorescences bisexual or staminate only. Staminate flowers with petals; hair tuft in centre. Fruits well dehiscing woody capsules

30. Croton

46b.

Leaves basally without or with 2 glands near point of petiole insertion. Hairs only stellate. Inflorescences usually unisexual. Staminate flowers without petals; centre without hair tuft. Fruits indehiscent to tardily dehiscent, often fleshy capsules, drupes or berries or clearly dehiscent capsules (then either sepals very large in fruit or leaves in whorls, subsessile, with narrow heart-shaped base).

47

47a.

Leaves either alternate, with glands at insertion (not too distinct) and with long pistil (more than 1 cm) or leaves whorled and subsessile with narrow heart-shaped base. Sepals distinct, valvate (touching, not overlapping); in fruit often strongly enlarging. Inflorescences terminal, racemes or raceme-like panicles; bracts with glands

48

47b.

Leaves alternate, though sometimes because of candelabriform growth habit in pseudo-whorls but then not subsessile and usually without heart-shaped base. Style absent or short, less than 5 mm long. Sepals either minute or imbricate (overlapping), never enlarging in fruit. Inflorescences cauliflorous, ramiflorous, or axillary racemes; bracts without glands

49

48a.

Leaves alternate, petiole long. Sepals not enlarging in fruit. Fruits drupaceous, indehiscent

24. Cleidiocarpon

48b.

Leaves alternate and with long petiole (then sepals enlarging in fruit) or in whorls and subsessile (then sepals not enlarging in fruit). Fruits clearly dehiscing capsules

36. Epiprinus

49a.

Leaves 1.5 to more times longer than wide, without raised glands near insertion. Calyx lobes distinct. Stamens 3-10, free, anthers 2-celled. Stigmas slender, free. Fruits with central column. Seeds with edible aril around them

9. Baccaurea

49b.

Leaves about as wide as long to 2 times as long, often with two raised glands at lower surface near insertion. Calyx lobes minute. Stamens 6-10, filaments fused at base, anthers 4-celled. Stigma a flat, 2-6-lobed, spreading disc. Fruits without central column. Seeds dry, without fleshy caruncle or aril

35. Endospermum

50a.

Rheophytic shrub (along/in rivers). Leaves narrowly elliptic (willow-like), with scale hairs beneath. Filaments united, branching off from central column and splitting dichotomously

48. Homonoia

50b.

Shrubs or trees, usually not rheophytic. Leaves variable, not willow-like (the only exception is Croton sp. 2, which is rheophytic with willow-like leaves lacking scale hairs, but with staminate flowers with free filaments!). Filaments free or only inner united and then not branching off from central column and splitting dichotomously

51

51a.

 

Leaves broadly-ovate, as broad as long, coarsely toothed, with a group of glands at leaf insertion. Stamens more than 200 with a purple gland on back of stamen connective. Pistillate flowers with a round disc.

60. Melanolepis

51b.

 

Leaves ovate to elliptic or broadly-ovate; when broadly ovate then not coarsely toothed though often lobed; none or 2 glands at leaf insertion. Stamens 5-250, without a gland. Pistillate flowers without a disc

52

52a.

 

Monoecious. Leaves white underneath, coarsely double toothed. Staminate flowers contracted into heads; pistillate flowers separate, solitary

22. Cladogynos

52b.

 

Monoecioius or dioecious. Leaves whitish or not underneath, usually finely (though sometimes double) toothed. Staminate flowers in racemes, spikes, or panicles (no heads), together with pistillate flowers or pistillate flowers several together on a separate inflorescence

53

53a.

 

Red exudate present (sometimes still visible at the cut). Calyx lobes with dorsally appendages. Inflorescences unisexual, terminal, very long, up to 40 cm, pendent. Leaf baldes not white underneath

70. Paracroton

53b.

 

Red exudate rare (few Croton spp.) or absent. Calyx lobes without appendages. Inflorescences axillary to terminal, unisexual (then leaves white underneath or inflorescences much shorter) or bisexual (then someimes also up to40 cm long)

54

54a.

Petals always absent. Ovary (or fruit) 2-locular (leaf blades up to 22 cm long, with basal glands, not peltate). Fruit densely greyish (greenish grey when dry) hairy. Stamens 5-8

65. Neoscortechinia

54b.

Petals present in at least staminate flowers, 4 or 5. Ovary 2-locular (then leaf blades up to 37 cm long, without basal glands, peltate) or 3-locular. Fruit densely brownish or greyish hairy or with scattered hairs when dry. Stamens 10-20 or ca. 75

55

55a.

Stamens 10-20. Inflorescences bisexual with basally pistillate flowers or staminate only. Fruits usually not brown tomentose; seeds naked. Leaf blades usually less than 20 cm long (some species with larger leaves but then not whitish underneath), white underneath or not, hairs stellate, lepidote or scale-like; with 2 (inconspicuous) glands on the upper or lower base of the blade or midrib or on the petiole apex, but never with a row of glands near base of blade

30. Croton

55b.

Stamens ca. 75. Inflorescences unisexual. Fruits brown tomentose; seeds with a thin fleshy layer. Leaf blades large, usually more than 20 cm long, white underneath, hairs stellate; glands absent at point of petiole insertion but a row of macular glands present beneath

81. Sumbaviopsis

56a.

Inflorescences opposite to the leaves (sympodial growth). Leaves with translucent dots (hold leaf against light)

82. Suregada

56b.

Inflorescences terminal, axillary, or rami- to cauliflorous, usually not opposite, if opposite then leaves not punctate

57

57a.

Flowers and fruits single per leaf axil or in axillary fascicles (no inflorescence axis present); fruits without rows of short spines. (Always boil dried or fresh flowers and analyse them under a microscope in water, this group is difficult to identify, because they all look similar)

58

57b.

Flowers and fruits in racemes, spikes, thyrses or panicles; fruits with or without rows of short spines

86

58a.

Staminate flowers with stamens in dichotomously branching groups or united into a long column from which the filaments branch off alternately. Ovary and fruits covered with stinging hairs or stinging hairs on tubercles

59

58b.

Staminate flowers with free stamens or filaments basally united or completely united and stamens in a circle, not branching off alternately or splitting dichotomously. Ovary and fruits glabrous or covered with non-stinging hairs.

60

59a.

Stipules obovate, asymmetric. Leaf base broadly attenuate. Stamens united into a long column from which the filaments branch off alternately. Ovary and fruit without tubercles, but completely covered with stinging hairs

18. Chaetocarpus

59b.

Stipules triangular, symmetric. Leave base narrowly emarginate. Stamens in dichotomously branching groups. Ovary and fruit covered with tubercles, each tubercle with a stinging hair

53. Lasiococca

60a.

Staminate flowers present

61

60b.

Pistillate flowers or fruits present

74

61a.

Petals present

62

61b.

Petals absent

67

62a.

Petals larger than sepals. Disc absent

63. Microdesmis

62b.

Petals shorter to slightly longer than sepals. Disc or disc lobes present

63

63a.

Stamens free

64

63b.

Stamens united pistillode on top

65

64a.

Disc a large 5-lobed ring. Stamens 3-6, on the disc

2. Actephila

64b.

Disc annular or lobed, lobes petal-like, 10 or 5 V-shaped. Stamens 5 or 6, on the receptacle

54. Leptopus

65a.

Petals shorter to longer than sepals. Leaf blades 1-2.5 by 0.7-1.6 cm, glabrous above, variously hairy underneath

20. Chorisandrachne

65b.

Petals shorter than sepals. Leaf blades 1.5-28 by 0.5-12 (always some larger than 2.5 by 1.6 cm), completely glabrous to hairs on both sides

66

66a.

Fruits drupes. (Leaves usually dull greyish brown when dry, with scalariform venation and in one genus section nerves ending in marginal vein, in other section ending before margin)

17. Bridelia

66b.

Fruit capsule. (Leaves usually shiny, different colours when dry, with indistinct venation, ending before margin)

26. Cleistanthus

67a.

Stamens free

68

67b.

Stamens united

71

68a.

Stamens few to many, around a broad, lobed or folded disc (absent in Drypetes roxburghii). Leaf base asymmetric

33. Drypetes

68b.

Stamens 3, 4 or 5. Disc absent or outside stamens (lobes or ring). Leaf base asymmetric or symmetric

69

69a.

Sepals 4. Disc annular. Stamens 4

58. Margaritaria

69b.

Sepals 5 or 6. Disc lobed or absent. Stamens 3 or 5

70

70a.

Sepals 5, free. Disc lobed. Stamens 5, long exerted from flower

41. Flueggea

70b.

Sepals 6, united. Disc absent. Stamens 3, not exserting flower

16. Breynia

71a.

Disc present

72. Phyllanthus

71b.

Disc absent (though sepals scales sometimes present)

72

72a.

Sepals without scales. Stamens with triangular appendages on the connectives

43. Glochidion

72b.

Sepals with scales inside, or 3 sepal lobes folded inwards and grown together. Stamens without connective appendages

73

73a.

Calyx bell-shaped or urceolate (then flowers narrow) or calyx disc-shaped and flowers more than 2 mm wide not coastal

16. Breynia

73b.

Calyx disc-shaped. Flower up to 1.3 mm in diameter coastal

83. Synostemon

74a.

Stigmas broad, flat, fan- to almost kidney-shaped. Fruit drupaceous. Leaf base asymmetric

33. Drypetes

74b.

Stigmas slender, round. Fruits drupaceous or capsular, then dry to fleshy and tardily dehiscing. Leaf base symmetric or asymmetric

75

75a.

Sepals 4. Fruits capsular, dehiscing irregularly. Seeds covered by fleshy, purple-blue aril

58. Margaritaria

75b.

Sepals 3, 5 or 6. Fruits drupaceous or regularly dehiscing capsules. Seeds naked or with an aril of different colour

76

76a.

Flowers single on long, more than 1 cm, pedicel; disc broad, annular, 5-lobed; petals present. Sepals often enlarging in fruit to about 1 cm long (not all species)

77

76b.

Flowers usually in groups, pedicel absent or shorter than 1 cm; disc absent, lobed or broadly annular; petals present or absent. Sepals usually not enlarging in fruit, but less than 1 cm long

78

77a.

Leaf blades 7-30 cm long. Stamens 3-6, free or basally united

2. Actephila

77b.

Leaf blades1-2.5 cm long. Stamens 5, united into a short androphore 20. Chorisandrachne

78a.

Petals present. Disc absent or present. Fruits drupaceous or capsular; if capsular then dry, with slender column (woody herbs or rarely shrubs to trees) or broad triangular basal fruit remnant left with column after dehiscence

79

78b.

Petals absent. Shrubs to trees. Fruits capsular, dry or fleshy, usually only column left, sometimes broad and triangular, but then disc absent

82

79a.

Petals longer than sepals. Disc absent. Fruit drupaceous, 2- or 3-locular. Locules with 1 ovule

63. Microdesmis

79b.

Petals shorter than sepals or if longer, then fruit capsular. Disc annular or lobed. Fruit drupaceous and then 1- or 2-locular or capsular. Locules with 2 ovules

80

80a.

Disc lobed (lobes like petals) or annular, then not divided into outer flat disc and inner cupular disc. Fruits capsular

54. Leptopus

80b.

Disc annular, divided in outer flat ring and inner cupular ring partly enveloping ovary (splitting during fruit-set). Fruits capsular or drupaceous

81

81a.

Ovary 2-locular (in fruit often becoming 1-locular). Fruit drupe. (Leaves usually dull greyish brown when dry with scalariform venation and in one genus section nerves ending in marginal vein, in other section ending before margin)

17. Bridelia

81b.

Ovary 3-locular. Fruit capsule. (Leaves usually shiny, different colours when dry with indistinct venation, ending before margin)

26. Cleistanthus

82a.

Flowers (or fruits basally with remnants) with disc

83

82b.

Flowers and fruits without disc

84

83a.

Sepals 5. Leaf base symmetric. Disc annular. Style distinct, 0.5-0.7 mm long

41. Flueggea

83b.

Sepals usually 6. Leaf base usually asymmetric. Disc separate lobes. Style usually absent, stigmas usually sessile

72. Phyllanthus

84a.

Ovary 3-25-locular (usually 3-locular). Styles usually united in a knob or column, toothed at the apex, sometimes free, then 2-2.5 mm long and flower with 2(3) sepals (G. sericeum)

43. Glochidion

84b.

Ovary 3-locular. Sepals 6. Styles either free and shorter than 2 mm or if united, split and lobes spreading like crescent-moons

85

85a.

Sepals united, bell-shaped or urceolate or sepals free and spreading horizontally. Seeds smooth not coastal

16. Breynia

85b.

Sepals free, erect. Seeds ornamented coastal

83. Synostemon

86a.

Leaves with 2 glands near or at blade insertion; these in various positions, either

- petiole with 2 subapical glands or

- leaves on upper or lower side with basally either 2 raised glands at insertion, or

- with (1) 2 (more) subbasal submarginal glandular areas (black areas), or

- leaves with two subbasal glands in margin.

Check several leaves, microscope!

87

86b.

Leaves without basal glands at insertion, or glandular, subbasal areas, or subbasal glands in margin

108

87a.

Leaf margin entire (though somewhat wavy)

88

87b.

Leaf margin dentate, serrate or crenate

96

88a.

Leaves with one or three pairs (latter sometimes grown together) of glands subbasally in margin (microscope!)

89

88b.

Leaves with glands at insertion or with subbasal submarginal glandular areas

90

89a.

Plant in mangrove. Leaf margin with one pair of glands (actually margin not entire, but sometimes extremely minutely serrate). Latex white. Staminate flowers with 3 free stamens. Pistillate flowers with 3 sepals

39. Excoecaria (agallocha)

89b.

Plant in non-mangrove areas. Leaf margin with three pairs of glands (though sometimes grown together forming black stripe in margin). Latex absent or watery, translucent. Staminate flowers with more than 100 stamens, united in groups. Pistillate flowers with 6 sepals

79. Spathiostemon

90a.

Leaves cordate, or broadly ovate to deltoid (about as long as broad)

91

90b.

Leaves ovate-elliptic to obovate (longer than broad).

92

91a.

Leaves broadly ovate to deltoid, glands at top of petiole hardly raised, or confluent into one gland. Inflorescences unbranched thyrses. Bracts of staminate flowers with 2 large glands. Petals absent. Pistillate flowers with glandular stigmata. Staminate flowers distinctly zygomorphic. Latex white.

47. Homalanthus

91b.

Leaves cordate to broadly ovoid, glands at top of petiole distinctly raised. Inflorescences (branching) panicles. Bracts of staminate flowers without glands. Petals more than 1 cm long. Pistillate flowers without glands on the stigma. Staminate flowers distinctly zygomorphic. Latex absent

87. Vernicia

92a.

Plants monoecious, inflorescences bisexual. Petals present, at least in staminate flowers. Stamens 3-5, joined. Ovary 3-locular; stigmas split. White latex absent. Fruits capsular. Leaves with glands at point of petiole insertion

86. Trigonostemon

92b.

Plants mono- or dioecious. Petals absent. Stamens 2-4 or 10-20, free. Ovary 2-4-locular; stigmas split or not. White latex present or absent. Fruits berries or capsules. Leaves with glands at insertion or subbasal glandular areas.

93

93a.

Petiole with two (sub)apical glands (then basal nerves part of margin) or leaf subbasally with black glandular areas on lower surface

94

93b.

Leaf blade at point of insertion with two glands on upper side; basal nerves above margin

95

94a.

Petiole without glands. Leaves peltate or not, with black subbasal submarginal glandular areas on lower surface; basal nerves free of margin. Inflorescences branching. Fruits berries

10. Balakata

94b.

Petiole with two subapical glands. Leaves never peltate, without glandular areas near base (but with a row of marginal glands); basal part of lowest nerves forming part of margin. Inflorescences unbranched. Fruits capsular, seeds persistent on column after dehiscence

85. Triadica

95a.

Leaves ovate to obovate, glabrous to densely pilose. Inflorescences spikes, often with flowers very densely spaced (rachis invisible). Stamens 2-4. Fruits 0.7-2.2 cm long

7. Aporosa

95b.

Leaves long obovate, glabrous. Inflorescences big subterminal and terminal panicles, flowers well separated. Stamens 10-20. Fruit 5-6 cm long

34. Elateriospermum

96a.

Staminate flowers in dense spikes, each flower with a thick staminal column with 2 or 3 whorls or anthers above each other. Pistillate flowers single, calyx very tightly enveloping flower when young. Ovary 5-20-locular. Stigma saucer-shaped with dentate margin. Fruits 8-9 cm in diameter. Introduced, often in temple compounds. Leaves cordate at base, nerves many, under right angles with midrib

49. Hura

96b.

Staminate flowers in dense spikes or not. Stamens free or only filaments united and anthers free. Pistillate flowers single or in an inflorescence, calyx free from pistil. Ovary up to 4-locular. Stigmas linear. Fruits much smaller

97

97a.

Deciduous tree, flowering when not in leaf. Branchlets thick, soft, spongy, shriveled when dry. Glands on bracts large. Fruits dehiscing irregularly

40. Falconeria

97b.

Evergreen or deciduous plants, flowering and fruiting when in leaf. Branchlets slender, with normal wood, not shriveling when dry. Glands on bracts absent or small. Fruits dehiscing regularly

98

98a.

Leaves with one pair of glands subbasally in margin (microscope!). In mangrove

39. Excoecaria (agallocha)

98b.

Leaves with glands basally at point of petiole insertion or next to insertion. Outside mangrove

99

99a.

Petals present, at least in staminate flowers (if absent in pistillate flowers then plants monoecious). Fruits either:

- small, dry capsular and flattened above (Colobocarpos), or

- with fleshy exocarp and mesocarp and woody endocarp (more than 2.5 cm high; Ostodes), or

- dry capsular, with rounded lobes (Trigonostemon, then: seeds naked and leaves without round glands, leaves often triplinerved at base; petals usually drying blackish)

100

99b.

Petals absent. Fruits fleshy or dry capsular, lobes rounded, less than 2.5 cm high. Seeds naked (then Cleidion: round glands on upper side of leaves) or with aril or caruncle

102

100a.

Stamens 3-5, joined. Fruit dry capsular, lobes with rounded apices, less than 2.5 cm long

86. Trigonostemon

100b.

Stamens 12-35, free or partly joined. Fruit either fleshy and large, more then 2.5 cm long or dry capsular with flattened apex, less than 2.5 cm long

101

101a.

Only staminate flowers with petals, about as long as sepals. Staminate flowers with central tuft of hairs. Pistillate flowers without disc. Fruit dry capsule, small, less then 2.5 cm, with flattened apex

29. Colobocarpos

101b.

Staminate and pistillate flowers with petals, longer than sepals. Staminate flowers without central dot of hairs. Pistillate flowers with annular disc. Fruit fleshy, large, more than 2.5 cm, with rounded apex lobes

67. Ostodes

102a.

Herbs, 13-34 cm high. Stamens 3 or 4 (or 9). Pistillate flowers with 3 strap-like disc lobes. Fruits 3-5 mm in diameter

62. Micrococca

102b.

Woody herbs to trees, more than at least 1 m high. Stamens 3 to many (if 3 or 4, then plants dioecious (Aporosa) or inflorescences bisexual (Shirakiopsis))

103

103a.

Leaves with row(s) of round, yellow glands on upper and lower surface, lower surface with round, hairy domatia in nerve axils. Anters 4-celled, cells in two pairs above each other

25. Cleidion

103b.

Leaves without round, yellow glands, nor hairy domatia. Stamens 2-celled or 4-celled, but then cells to each other (normal situation in moste plants)

104

104a.

Bracts in inflorescence with glands. Sepals or calyx lobes 3. Leaves with 2 marginal glands next to petiole, not on top at point of petiole insertion. Leaf serration very fine

78. Shirakiopsis

104b.

Bracts in inflorescence without glands. Sepals or calyx lobes 3-6. Leaves with 2 (confluent) glands at point of petiole insertion or next to petiole (then leaf serration wide and crude)

105

105a.

Staminate flowers usually in very dense, short spikes; stamens 2-4. Disc absent. Pistil with 2 ovules per locule (fruits with 2 seeds per locule, but usually one abortive and one developed). Fruits often fleshy capsules

7. Aporosa

105b.

Staminate flowers usually in lax panicles or racemes; stamens 10-50. Disc present. Pistil with 1 ovule per locule (fruits with 1 seed per locule). Fruits dry capsules

106

106a.

Flowers in racemes. Stamens 20-50, connective short, straight, anther locules separate, diverging, only basally attached to connective (stamen Mickey Mouse-like). Pistillate sepals without teeth; stigmas slender, not widened. Seeds completely covered by fleshy aril

23. Claoxylon

106b.

Flowers in panicles. Stamens 10-ca. 30, connective ^-shaped (upside down V) with anthers along upper edge, attached to connective. Pistillate sepals with or without teeth; stigmas slender or wing-like. Seeds with caruncle (fleshy structure on apical part of seed only)

107

107a.

Sepals imbricate (overlapping in bud). Staminate flowers: sepals 4 or 5; disc lobed or annular; stamens 10-30. Pistillate sepals often long, often with a glandular tooth per margin; stigmas often widening into wing

11. Baliospermum

107b.

Sepals valvate (touching in bud). Staminate flowers: sepals 3 or 4; disc lobed; stamens ca. 30. Pistillate sepals bract-like, without glandular teeth; stigmas not widening, narrow

19. Chondrostylis

108a.

Sepals 2, broad lobes in all flowers. Petals absent. Ovary 2-locular. Fruits leathery berries

109

108b.

Sepals 2-5, when 2 sepals then petals present. Petals absent or present. Fruits drupaceous, berry-like or capsular

110

109a.

Stamens 2. Inflorescences branching. Fruits less than 1.1 cm in diameter

10. Balakata

109b.

Stamens 12-16. Inflorescences unbranched. Ovary 2-many-locular. Fruits large, 1.2-3 cm in diameter

73. Pimelodendron

110a.

Axillary buds in row above each other (check especially older branches). Stipules not on internode, but above or below leaves, check scars on older branches! Leaves (narrowly) elliptic to obovate, long. Inflorescences with very broad, convex bracts, covering flowers, caducous. Flowers with petals

3. Agrostistachys

110b.

Axillary buds usually only one visible, at most in circular groups. Stipules absent or when present next to leaf petiole on node. Leaves ovate to obovate, short to long. Inflorescences without broad bracts. Flowers with or without petals

111

111a.

Leaves with entire (or somewhat wavy) margin, sometimes lobed. (Use hand lens or microscope)

112

111b.

Leaves with crenate, serrate or dentate margin (N.B. sometimes only small, glandular teeth protruding)

143

112a.

Leaves lobed or not, variegated (conspicuously yellow or purplish venation, or purplish leaves), sometimes apex of leaf separate from rest of blade. Cultivated, ornamental shrubs

28. Codiaeum

112b.

Leaves not lobed, not variegated, apex always part of rest of blade. Usually not cultivated, certainly not as ornamental

113

113a.

Stamens more than 100, united into 4-7 bifurcating androphores. Leaf blade at base with few glands in margin at each side, sometimes confluent or submarginally, near base, small black-dotted glands adaxially. Stigmas 3, not split, glandular above

114

113b.

Stamens 2-250, free to inner united to all united; filaments simple, not branching dichotomously. Leaf blade at base without glands in margin. Stigmas variable, often split, if not split then often glandless above

115

114a.

Leaf blade with submarginal, small black-dotted glands adaxially Ovary and fruit with tubercles with on top a stinging hair; style present. Pistillate flowers single in leaf axils

53. Lasiococca

114b.

Leaf blade at base with few glands in margin at each side. Ovary and fruit smooth; style absent. Pistillate flowers in racemes

79. Spathiostemon

115a.

Inflorescences terminal, long (15-30 cm) spikes, usually hanging. Flowers with petals, without a disc. Fruits drupaceous. Leaves with short, completely pulvinate pedicels

42. Galearia

115b.

Inflorescences cauliflorous to terminal, racemes, panicles, spikes, cymes, usually less long. Flowers with or without petals, when with petals then disc present, at least in staminate flowers. Fruits capsules, berries or drupes. Leaves with long to short pedicels, sometimes completely pulvinate

116

116a.

Leaves without stipules, only bracts present at base of new branches. Staminate flowers usually with petals (shorter than sepals), pistillate ones without

117

116b.

Leaves with stipules (when caducous scars next to leaves). Both sexes either with or without petals, petals longer than sepals

118

117a.

Flowers in cymes or umbels (all flowers branching off from same node in inflorescence, sometimes one or two flowers branching off from lower node). Sepals without long glandular fimbriae along margin. Leaves never panduriform

13. Blachia

117b.

Flowers in terminal racemes. Sepals with long glandular fimbriae along margin. Leaves often panduriform

80. Strophioblachia

118a.

Flowers with petals. Stamens 3-5, all united, or 10-20, only inner united. Sepals 5, often enlarging in fruit. Seeds without fleshy appendage, naked

119

118b.

Flowers without petals. Stamens 2-250, free or united. When united 3 or 6 stamens, then sepals 6. Seeds naked or with caruncle (fleshy appendage) or covered by aril

120

119a.

Stamens 10-20. Sepals enlarging in fruit. Petals usually white. Inflorescences unisexual. Leaves not or only slightly triplinerved at base

32. Dimorphocalyx

119b.

Stamens 3-5. Sepals usually not enlarging in fruit (enlarging in T. phyllocalyx). Petals white, yellow, red or dark purple (often drying blackish). Inflorescences usually bisexual. Leaves often basally triplinerved

86. Trigonostemon

120a.

Staminate flowers present

121

120b.

Pistillate flowers or fruits present

132

121a.

Stamens up to 12, free or (partially) united

122

121b.

Stamens 14-250, free

129

122a.

Stamens free

123

122b.

Stamens united

128

123a.

Stamens 12, around broad central disc. Leaf base asymmetric

33. Drypetes (dasycarpa)

123b.

Stamens 2-10; disc absent, or disc lobed or disc annular and then outside or inside stamens. Leaf base usually symmetric (to slightly asymmetric)

124

124a.

Disc present, annular or lobed

125

124b.

Disc absent

126

125a.

Disc annular, or separate lobes, or cushion-shaped and enclosing stamens. Stamens alternating with sepals; connective small, with on top separate anther locules (resembling Mickey Mouse in shape)

6. Antidesma

125b.

Disc consisting of 5 lobes. Stamens on sepals; anther locules united, along connective

41. Flueggea

126a.

Petioles slender throughout, not pulvinate. Stamens 3, exserted. Angle of secondary veins with midrib 75-80

44. Gymnanthes

126b.

Petioles apically and/or basically pulvinate (thickened). Stamens 2-10, usually not exserted. Angle of secondary veins with midrib sharper, less than 75

127

127a.

Stamens 2-4. Staminate inflorescences 0.5-6.2(-9.8) cm long, glabrous to densely hairy. Petiole usually distinctly pulvinate at both ends, sometimes only apically, 4-51 mm long. Candelabriform branching pattern absent; leaves distichous on terminal branches

7. Aporosa

127b.

Stamens 3-10. Staminate inflorescences up to 2.3-28 cm long, densely hairy. Petiole usually only apically pulvinate, 4-184 mm long. Candelabriform branching pattern weak to strong; leaves spirally arranged

9. Baccaurea

128a.

Disc absent. Anthers underneath bent part of filament. Sepals with scales inside

16. Breynia

128b.

Disc (lobes) present, sometimes resembling petals. Anthers at end of filaments. Sepals without scales

72. Phyllanthus

129a.

Stamens 14-35

130

129b.

Stamens 100-250

131

130a.

Leaves often in pseudo-whorls; without glands and domatia underneath

14. Blumeodendron

130b.

Leaves alternate; basally with 1-4 circular glands, pocket domatia with hairy margin in nerve axils underneath

77. Sampantaea

131a.

Disc absent, stamens without glands. Inflorescences up to 1 cm long with up to 6 single flowers. Stipules with laciniate margin

45. Hancea (subpeltata)

131b.

Fleshy glands at base of stamens. Inflorescences more than 2 cm long, more than 6 flowers, usually grouped per node. Stipules with entire margin

75. Ptychopyxis

132a.

Sepals imbricate (overlapping). Ovary with 2 ovules per locule (in fruit check for abortive seeds per locule, often only 1 ovule developing into seed, other abortive); 1-8-locular

133

132b.

Sepals valvate (touching). Ovary with 1 ovule per locule; 2- or 3-locular

139

133a.

Ovary and drupaceous fruit 1-locular. Fruit often laterally (or dorso-ventrally flattened); stigma apical to laterally. Annular disc present

6. Antidesma

133b.

Ovary and fruit 2-8-locular. Fruit capsular to drupaceous, never flattened; stigma (remnants) apical. Disc absent or present

134

134a.

Fruits hairy drupes, ca. 2 cm high. Stigmas with broad, flat, fan- to kidney-shaped apices (apices caducous, check only in flower). Terminal buds covered by large bracts, ca. 6 mm high, hairy. Leaves more than 10 cm long, base asymmetric

33. Drypetes (dasycarpa)

134b.

Fruits glabrous to hairy berries, fleshy to dry capsules, sometimes drupaceous, then usually smaller than 2 cm or leaves less than 10 cm long. Stigma apices not broadened, slender. Terminal buds at most covered by small bracts. Leaf base symmetric or asymmetric

135

135a.

Annular disc present; sepals 5. Inflorescences branching panicles

41. Flueggea

135b.

Disc absent or present, then often lobes and sepals 6. Inflorescences spikes or racemes, not branching

136

136a.

Sepals 6. Disc (lobes) present. Ovary 3(-8)-locular. Fruits dry capsules or drupes

72. Phyllanthus

136b.

Sepals 3-6. Disc absent. Ovary 2-4-locular. Fruits berries or dry or fleshy capsules

137

137a.

Sepals 6, spreading flat, basally united. Stigmas flat on ovary, smooth on upper surface, split and crescent moon-shaped

16. Breynia

137b.

Sepals 3-6, erect to spreading to reflexed, usually free. Stigmas erect, flat on ovary or descending along ovary, usually with papillae or lamellae on upper surface, split or not, not crescent moon-shaped

138

138a.

Fruits dehiscent, often fleshy capsules; seeds enclosed by a thin, fleshy, usually non-edible aril. Petiole usually distinctly pulvinate at both ends, sometimes only apically, 4-51 mm long. Candelabriform branching pattern absent. Leaves distichous on terminal branches, often drying blackish/bluish or yellowish, also brownish or greenish

7. Aporosa

138b.

Fruits berries to late dehiscing fleshy capsules; seeds enclosed by a fleshy and usually edible aril. Petiole usually only apically pulvinate, 4-184 mm long. Candelabriform branching pattern weak to strong. Leaves alternate, usually drying brownish or greenish

9. Baccaurea

139a.

Disc annular. Fruits large, tardily dehiscent capsules, usually more than 3 cm in diameter, glabrous. Leaves often in pseudo-whorls

14. Blumeodendron

139b.

Disc absent. Fruits well-dehiscing capsules, usually much smaller (when big densely hairy). Leaves alternate

140

140a.

Ovary and fruit single on short stalk, up to 1 cm long inflorescences, covered with spines. Stipules with laciniate margin

45. Hancea (subpeltata)

140b.

Ovary and fruit smooth, without spines, usually with more than 1 flower per inflorescence (usually 1 developed into fruit in Gymnanthes), inflorescences longer. Stipules with entire margin

141

141a.

Flowers with 3 sepals. Leaf blade abaxially with glands along the margin

44. Gymnanthes

141b.

Flowers with 3, 4, or 5 sepals. Leaf blades abaxially without glands along the margin

142

142a.

Flowers with 6 sepals. Leaves without glands and domatia underneath

75. Ptychopyxis

142b.

Flowers with 4 or 5 sepals. Leaves basally with 1-4 circular glands, pocket domatia with hairy margin in nerve axils underneath

77. Sampantaea

143a.

Woody herbs or small shrubs. Inflorescences bisexual with basally a pistillate flower. Margin of leaves with asperities (small silica thorns). Fruits with vertical rows of short spines. Staminate bracts with glands; stamens 3

64. Microstachys

143b.

Herbs to shrubs to trees. Inflorescences unisexual or bisexual with basally pistillate flower(s). Margin of leaves without asperities. Fruits smooth or armed, but spines not in rows. Staminate bracts without or with glands, but then stamens 3 or 8

144

144a.

Leaves palmately nerved with 5 or 7 nerves at base; margin slightly lobed

51. Jatropha (curcas)

144b.

Leaves pinnately nerved, at most triplinerved at base; margin not lobed

145

145a.

Staminate flowers present

146

145b.

Pistillate flowers or fruits present

157

146a.

Petals present

147

146b.

Petals absent

148

147a.

Stamens 10-20

32. Dimorphocalyx

147b.

Stamens 3-5

86. Trigonostemon

148a.

Stamens 2-8

149

148b.

Stamens 12 to many

152

149a.

Stamens 2-4

150

149b.

Stamens 8

151

150a.

Latex absent. Inflorescence bracts without glands. Flowers in tight groups, usually densely arranged along rachis. Stamens 2-4; sepals 3-6. Inflorescences unisexual

7. Aporosa

150b.

Latex present. Inflorescence bracts with glands. Flowers in lax groups, spaced along rachis. Stamens 3; sepals 3. Inflorescences usually bisexual, with basally pistillate flowers or unisexual and staminate

39. Excoecaria (cochinchinensis)

151a.

Leaves without stipellae at point of petiole insertion. Inflorescence bracts without glands. Inflorescences usually bisexual. Stamens free; anther cells free, elongate, erect or spreading, twisted. Often cultivated shrubs, often with reddish leaves

1. Acalypha

151b.

Either leaves basally with 2 stipellae at point of petiole insertion or inflorescence bracts with glands. Inflorescences unisexual. Stamens united on receptacle ring; anther cells normal, not elongated, not twisted

4. Alchornea

152a.

Calyx irregularly dehiscing. Stamens with (short filaments and) large, umbrella-shaped connective with 4 anther cells hanging from edge

15. Botryophora

152b.

Calyx regularly dehiscing. Stamens with normal small connective or with basally widened connective, not umbrella-shaped; anther cells 2

153

153a.

Disc absent

154

153b.

Disc present, either annular or separate glands (small knobs or strap-like with hair tuft on top) among stamens

155

154a.

Leaves 3.7-19 cm long with 11-14 nerve pairs; lower surface with hairy domatia

77. Sampantaea

154b.

Leaves 9.5-56 cm long with 19-32 nerve pairs; lower surface without domatia

88. Wetria

155a.

Leaf margin with glands in teeth at lower surface, thus not at end of teeth

11. Baliospermum

155b.

Leaf margin with glands at end of teeth

156

156a.

Inflorescence a panicle (branched)

19. Chondrostylis

156b.

Inflorescence a raceme (unbranched)

23. Claoxylon

157a.

Petals present. Ovary armed with muricae. Fruit muricate, about as broad as high. Stigmas apically split, less than 1 cm long

32. Dimorphocalyx (muricatus)

157b.

Petals seldom present (sometimes Trigonostemon). Ovary smooth. Fruits smooth or wrinkled, or muricate but then stigmas long, ca. 1 cm and undivided and fruit much longer than broad

158

158a.

Herbs to shrubs. Inflorescences bisexual, without glands on bracts, but bracts often large and with laciniate margin. Stigmas much branched (usually providing colour to the flowers). Often cultivated species, often with reddish leaves

1. Acalypha

158b.

Shrubs to trees. Inflorescences unisexual or bisexual, when bisexual then usually bracts with glands, bracts small, margin entire. Stigmas entire or (partly) bifid

159

159a.

Leaves with 2 stipellae at point of petiole insertion. Fruits longer than broad, often a bit muricate; stigmas undivided

4. Alchornea

159b.

Leaves without stipellae at point of petiole insertion. Fruits usually as broad as high or broader than high, smooth to wrinkled; stigmas undivided or (partly) divided

160

160a.

Inflorescences unisexual, bracts with glands. Leaf with round glands on upper (or lower) surface.

4. Alchornea

160b.

Inflorescences unisexual or bisexual, bracts with or without glands; when with glands inflorescences bisexual and leaves without round glands.

161

161a.

Inflorescences bisexual; bracts with glands

39. Excoecaria (cochinchinensis)

161b.

Inflorescences usually unisexual; bracts without glands

162

162a.

 Inflorescences panicles (branching) or cymose. Disc present

163

162b.

Inflorescences spikes or racemes (not branching). Disc present or not

166

163a.

Glands on lower side in teeth (teeth not ending in glands!). Pistillate sepals often with a glandular tooth per margin; stigmas often widening into wing

11. Baliospermum

163b.

Glands absent in leaf or teeth ending in gland. Pistillate sepals without glandular teeth; stigmas slender, not broadening

164

164a.

Pistillate sepals 3 or 4, tiny; disc large, more or less 6-8-lobed. Fruits capsules with 3 keeled angles

15. Botryophora

164b.

Pistillate sepals 5; disc annular or 5-lobed. Fruits smooth, without keels

165

165a.

Inflorescences unisexual. Pistillate flowers without petals; disc annular (often indistinct). Seeds carunculate (fleshy part on top)

19. Chondrostylis

165b.

Inflorescences bisexual (in fruit often not visible). Pistillate flowers with or without petals; disc often lobed. Seeds naked

86. Trigonostemon

166a.

Pistillate disc 5-lobed, sometimes larger than sepals, sepaloid; stigmas sessile, not forked. Fruits somewhat ribbed on sutures, usually densely tomentose. Seeds completely covered by an aril (locules uniovulate)

23. Claoxylon

166b.

Pistillate disc absent or annular to 5-lobed, small; stigmas sessile or on style, not forked or (partly) split. Fruits ribbed or not on sutures, glabrous to tomentose. Seeds naked or completely covered by an aril (then disc absent, locules biovulate)

167

167a.

Disc (glands) present. Locules with 1 ovule

86. Trigonostemon

167b.

Disc absent. Locules with 1 or 2 ovules (if with 2 then in fruit often only one develops into seed, look for abortive ovule next to seed)

168

168a.

Locules with 2 ovules (usually in fruit only one develops into seed, look for abortive ovule next to seed). Pistillate sepals 3-6, imbricate (overlapping in bud). Seeds covered by thin aril. Ovary 2-, 3- (or 4)-locular

7. Aporosa

168b.

Locules with 1 ovule. Pistillate sepals 4 or 5, valvate (touching in bud). Seeds naked. Ovary 3- (or 4)-locular

169

169a.

Leaves 3.7-19 cm long with 11-14 nerve-pairs; lower surface with hairy domatia

77. Sampantaea

169b.

Leaves 9.5-56 cm long with 19-32 nerve-pairs; lower surface without domatia

88. Wetria