How to use the key: This is an illustrated key for all Macaranga and Mallotus species of Borneo. The key is dichotomous, which means that each question consists of two choices (a and b). After you have decided which of the two choices fits your specimen best, you can continue with the next question by clicking on the number behind choice a or b. For each lead you can also see which species your specimen could still belong to (clicking on the species names takes you to their illustrated descriptions). You have reached the final identification when there is a species name, instead of a question number, behind the lead of your choice (click the species name and you will enter the illustrated description for that species).

Important: This key is valid for (semi-) adult plants only, i.e., it might not work for seedlings.

1a. Twigs hollow (usually ant inhabited)	2
Choices left: Macaranga aëtheadenia; Macaranga angulata; Macaranga bancana; Macaranga beccariana; Macaranga caladiifolia; Macaranga calcicola; Macaranga glandibracteolata; Macaranga havilandii; Macaranga hosei, Macaranga hullettii; Macaranga hypoleuca; Macaranga indistincta; Macaranga kingii; Macaranga lamellata; Macaranga motleyana; Macaranga pearsonii; Macaranga petanostyla; Macaranga puberula; Macaranga puncticulata; Macaranga recurvata; Macaranga rufescens; Macaranga trachyphylla; Macaranga umbrosa; Macaranga velutina; Macaranga velutiniflora; Macaranga winkleri; Macaranga winkleriella
1b. Twigs solid	38
Choices left: Macaranga amissa; Macaranga ashtonii; Macaranga auriculata; Macaranga baccaureifolia; Macaranga brevipetiolata; Macaranga conifera; Macaranga costulata; Macaranga depressa; Macaranga didymocarpa; Macaranga endertii: Macaranga fulva; Macaranga gigantea; Macaranga hosei; Macaranga kinabaluensis; Macaranga lowii var. lowii; Macaranga lowii var. kostermansii; Macaranga pachyphylla; Macaranga pearsonii; Macaranga pentaloba; Macaranga praestans; Macaranga pruinosa; Macaranga puberula; Macaranga puncticulata; Macaranga rarispina; Macaranga recurvata; Macaranga repando-dentata; Macaranga rostrata; Macaranga sarcocarpa; Macaranga spathicalyx; Macaranga strigosissima; Macaranga tanarius; Macaranga trichocarpa; Mallotus brachythyrsus; Mallotus dispar; Mallotus eucaustus; Mallotus floribundus; Mallotus griffithianus; Mallotus havilandii; Mallotus korthalsii; Mallotus lackeyi; Mallotus leucodermis; Mallotus macrostachyus; Mallotus miquelianus; Mallotus mollissimus; Mallotus moritzianus; Mallotus muticus; Mallotus paniculatus; Mallotus peltatus; Mallotus penangensis; Mallotus philippensis; Mallotus repandus; Mallotus resinosus; Mallotus stipularis; Mallotus subpeltatus; Mallotus sumatranus; Mallotus tiliifolius; Mallotus wrayi
2a. Leaves not lobed	3
Choices left: Macaranga bancana; Macaranga caladiifolia; Macaranga havilandii; Macaranga hullettii; Macaranga lamellata; Macaranga puncticulata; Macaranga recurvata; Macaranga umbrosa; Macaranga velutina; Macaranga winkleri; Macaranga winkleriella
2b. Leaves lobed	13
Choices left: Macaranga aëtheadenia; Macaranga angulata; Macaranga bancana; Macaranga beccariana; Macaranga calcicola; Macaranga glandibracteolata; Macaranga havilandii; Macaranga hosei, Macaranga hullettii; Macaranga hypoleuca; Macaranga indistincta; Macaranga kingii; Macaranga motleyana; Macaranga pearsonii; Macaranga petanostyla; Macaranga puberula; Macaranga rufescens; Macaranga trachyphylla; Macaranga umbrosa; Macaranga velutina; Macaranga velutiniflora
3a. Stipules erect to spreading	4
Choices left: Macaranga caladiifolia; Macaranga puncticulata; Macaranga recurvata; Macaranga winkleri
3b. Stipules recurved	7
Choices left: Macaranga bancana; Macaranga havilandii; Macaranga hullettii; Macaranga lamellata; Macaranga umbrosa; Macaranga velutina; Macaranga winkleriella
4a. Twigs strongly swollen between nodes, usually with large ant holes (ca. 2mm diameter), sometimes splitting open lengthwise; leaf lower surface glaucous or not; plant hairy or not	5
Choices left: Macaranga caladiifolia; Macaranga puncticulata
4b. Twigs not swollen between nodes, usually with small ant holes (ca. 1 mm diameter), not splitting open; lower leaf surface glaucous or not; plant completely glabrous	6
Choices left: Macaranga recurvata; Macaranga winkleri
5a. Shrub up to 6 m tall; leaf peltate margin length 2-8 cm, basal secondary veins arising almost perpendicular from midrib, leaf lower surface numerously gland dotted; fruits bright red-pink	Macaranga caladiifolia
5b. Shrub to small tree up to 15 m tall; leaf peltate margin 0.5-3.1 cm, basal secondary veins usually arising with a steeper angle from the midrib, leaf lower surface densely gland dotted; fruits green	Macaranga puncticulata
6a. Twigs not ant inhabited, without ant openings; stipules usually early caducous, usually erect; leaf lower surface glaucous, very densely gland dotted; fruits ca. 10 mm diameter	Macaranga recurvata
6b. Twigs ant-inhabited, with ant openings; stipules usually persistent, spreading; leaf lower surface not glaucous, numerously gland dotted; fruits ca. 3 mm diameter	Macaranga winkleri
7a. Stipules very long, 20-31 mm	8
Choices left: Macaranga lamellata; Macaranga umbrosa
7b. Stipules much shorter, 4-12 mm	9
Choices left: Macaranga bancana; Macaranga havilandii; Macaranga hullettii; Macaranga velutina; Macaranga winkleriella
8a. Leaf lower surface glaucous, gland dotted	Macaranga lamellata
8b. Leaf lower surface not glaucous, not gland dotted	Macaranga umbrosa
9a. Lower leaf surface densely hairy (velvety)	Macaranga velutina
9b. Lower leaf surface glabrous or sparsely hairy on veins only	10
Choices left: Macaranga bancana; Macaranga havilandii; Macaranga hullettii; Macaranga winkleriella
10a. Stipules not surrounding the twig completely; lower leaf surface glaucous or not	11
Choices left: Macaranga havilandii; Macaranga winkleriella
10b.Stipules completely surrounding the twig; lower leaf surface not glaucous	12
Choices left: Macaranga bancana; Macaranga hullettii
11a. Twigs glaucous; leaves large, 24-29 cm long by 15.5-22 cm wide, peltate margin length > 5 cm, leaf lower surface usually glaucous; fruits 4-5-locular, 8-11 mm diameter	Macaranga havilandii
11b. Twigs not glaucous; leaves small, 14-25 cm long by 10-16.5 cm wide, peltate margin length < 6 cm, leaf lower surface not glaucous; fruits 2-locular, ca. 3 mm diameter	Macaranga winkleriella
12a. Twigs glabrous; leaves broadly ovate (length/width-ratio 0.92-1.43), lower leaf surface numerously gland dotted, secondary veins ending in the margin; staminate bracteole margins entire; pistillate inflorescence branched; fruit without horn-like appendages	Macaranga bancana
12b. Twigs glabrous to hairy; leaves narrowly ovate (length/width-ratio 1.28-2.60), lower leaf surface not or sparsely gland dotted, secondary veins usually not ending in the margin; staminate bracteole margins fimbriate; pistillate inflorescence not branched; fruit with horn-like appendages	Macaranga hullettii
13a. Stipules erect to spreading	14
Choices left: Macaranga beccariana; Macaranga hosei; Macaranga hypoleuca; Macaranga pearsonii; Macaranga puberula; Macaranga rufescens
13b. Stipules recurved	19
Choices left: Macaranga aëtheadenia; Macaranga angulata; Macaranga bancana; Macaranga calcicola; Macaranga glandibracteolata; Macaranga havilandii; Macaranga hullettii; Macaranga indistincta; Macaranga kingii; Macaranga motleyana; Macaranga petanostyla; Macaranga trachyphylla; Macaranga umbrosa; Macaranga velutina; Macaranga velutiniflora
14a. Stipules narrowly ovate to triangular, 2-10 mm wide, clearly not surrounding the twig	15
Choices left: Macaranga beccariana; Macaranga hypoleuca
14b. Stipules broadly ovate to rounded, 5-20 mm wide, (almost) completely surrounding the twig	16
Choices left: Macaranga hosei; Macaranga pearsonii; Macaranga puberula; Macaranga rufescens
15a. Leaves central lobe more than 2.2 times longer than wide, lateral lobes 9.5-22 cm long	Macaranga beccariana
15b. Leaves central lobe less than 1.8 times longer than wide, lateral lobes 5.5-14 cm long	Macaranga hypoleuca
16a. Twigs densely hairy, not glaucous	Macaranga puberula
16b. Twigs glabrous, usually glaucous	17
Choices left: Macaranga hosei; Macaranga pearsonii; Macaranga rufescens
17a. Stipules erect, early caducous; leaf base with several prominently enlarged conical glands along the margin	Macaranga pearsonii
17b. Stipules spreading, persistent; leaf base with conical glands lacking or inconspicuous	18
Choices left: Macaranga hosei; Macaranga rufescens
18a. Leaf margin with prominent conical glands, lower leaf surface glabrous or with erect spiny hairs along veins; inflorescence axes up to 20-40 cm long, with unbranched basal axis > 50% of total length	Macaranga hosei
18b. Leaf margin with inconspicuous conical glands, lower leaf surface furfuraceous (scaly), usually without dense erect hairs along the veins; inflorescence axes up to 10-28 cm long, with unbranched basal axis < 50% long	Macaranga rufescens
19a. Leaf uppersurface completely covered with hairs, feeling like sandpaper	Macaranga trachyphylla
19b. Leaf surface glabrous to partly hairy on veins, not feeling like sandpaper	20
Choices left: Macaranga aëtheadenia; Macaranga angulata; Macaranga bancana; Macaranga calcicola; Macaranga glandibracteolata; Macaranga havilandii; Macaranga hullettii; Macaranga indistincta; Macaranga kingii; Macaranga motleyana; Macaranga petanostyla; Macaranga umbrosa; Macaranga velutina; Macaranga velutiniflora
20a. Twigs hairy	21
Choices left: Macaranga calcicola; Macaranga hullettii; Macaranga indistincta; Macaranga petanostyla; Macaranga velutina
20b. Twigs glabrous	25
Choices left: Macaranga aëtheadenia; Macaranga angulata; Macaranga bancana; Macaranga glandibracteolata; Macaranga havilandii; Macaranga hullettii; Macaranga kingii; Macaranga motleyana; Macaranga petanostyla; Macaranga umbrosa; Macaranga velutina; Macaranga velutiniflora
21a. Petioles glabrous; leaves 28-44 by 22-42 cm, peltate margin length 4.8-10.5 cm, central lobe 11-20 by 12.5-26 cm, lateral lobe length 4-10 cm long, lower leaf surface glabrous or with few hairs on veins	Macaranga petanostyla
21b. Petioles glabrous to densely hairy; leaves 12-35 by 5-25 cm, peltate margin length 0.2-6 cm; central lobe 6-15 by 6.5-14 cm, lateral lobe length 0.5-6.5 cm, lower leaf surface glabrous to densely hairy	22
Choices left: Macaranga calcicola; Macaranga hullettii; Macaranga indistincta; Macaranga velutina
22a. Lower leaf surface densely hairy, often velvety	23
Choices left: Macaranga indistincta; Macaranga velutina
22b. Lower leaf surface glabrous to hairy on veins only	24
Choices left: Macaranga calcicola; Macaranga hullettii
23a. Twigs densely hairy; leaves large 21-35 by 15-25 cm, peltate margin length 2.5-6 cm, lateral lobe length 2-6.5 cm; staminate bracts fimbriate; fruits with horn like appendages	Macaranga indistincta
23b. Twigs sparsely to densely hairy; leaves smaller 17-24 by 14-21 cm, peltate margin length 1.2-3.3 cm, lateral lobe length 0.5-3 cm; staminate bracts entire; fruits without horn like appendages	Macaranga velutina
24a. Only found on limestone, in lowlands up to ca. 200 m; leaves almost as wide as long, length/width-ratio 1.00-1.23, secondary veins 8-10, central lobe length 9-6 cm, secondary veins ending in the margin; staminate bracts entire; fruits without horn like appendages	Macaranga calcicola
24b. Not restricted to limestone, lowland to montane up to ca. 1400 m; leaves clearly longer than wide, ratio 1.28-2.60, secondary veins 9-18, central lobe length 12-14 cm, secondary veins usually not ending in the margin (looping); staminate bracts fimbriate; fruits with horn like appendages	Macaranga hullettii
25a. Stipule length 20-33 mm	26
Choices left: Macaranga kingii; Macaranga umbrosa
25b. Stipule length 4-12 mm	27
Choices left: Macaranga aëtheadenia; Macaranga angulata; Macaranga bancana; Macaranga glandibracteolata; Macaranga havilandii; Macaranga hullettii; Macaranga motleyana; Macaranga petanostyla; Macaranga velutina; Macaranga velutiniflora
26a. Leaves deeply 5 lobed, lateral lobe lengths up to 22-29 cm	Macaranga kingii
26b. Leaves shallowly 3 lobed, lateral lobe lengths up to 1.5-4 cm	Macaranga umbrosa
27a. Stipules and stipule scars clearly not surrounding the twig completely; twigs usually glaucous	28
Choices left: Macaranga aëtheadenia; Macaranga glandibracteolata; Macaranga havilandii; Macaranga motleyana
27b. Stipules and stipule scars (almost) surrounding the twigs completely; twigs glaucous or not	32
Choices left: Macaranga aëtheadenia; Macaranga angulata; Macaranga bancana; Macaranga hullettii; Macaranga petanostyla; Macaranga velutina; Macaranga velutiniflora
28a. Lower leaf surface densely hairy	29
Choices left: Macaranga aëtheadenia; Macaranga glandibracteolata
28b. Lower leaf surface glabrous	30
Choices left: Macaranga aëtheadenia; Macaranga havilandii; Macaranga motleyana
29a. Basal leaf margin with conspicuously large glands, clearly larger than glands along the apical leaf margin	Macaranga aëtheadenia
29b. Basal leaf margin with much smaller glands, same size as glands along the apical leaf margin	Macaranga glandibracteolata
30a. Basal leaf margin with conspicuously large glands, clearly larger than glands along the apical leaf margin	Macaranga aëtheadenia
30b. Basal leaf margin with glands much smaller, same size as glands along the apical leaf margin	31
Choices left: Macaranga havilandii; Macaranga motleyana
31a. Small treelet less than 6 m tall and 3 cm dbh, developing several slender, usually unbranched stems from one individual; leaves irregularly dissected, thin and delicate, peltate margin length 5-7 cm; staminate flowers with 1 stamen; fruits red coloured; only known from Sarawak and Brunei	Macaranga havilandii
31b. Tree up to 30 m tall and 30 cm dbh; leaves thickly leathery, peltate margin length 2.3-6 cm; staminate flowers with 2-3 stamens; fruit not red, glaucous; found all over Borneo	Macaranga motleyana
32a. Basal leaf margin with conspicuously large glands, clearly larger than glands along the apical leaf margin	Macaranga aëtheadenia
32b. Basal leaf margin with glands much smaller, same size as glands along the apical leaf margin	33
Choices left: Macaranga angulata; Macaranga bancana; Macaranga hullettii; Macaranga petanostyla; Macaranga velutina; Macaranga velutiniflora
33a. Petiole densely covered with very short hairs; lower leaf surface densely hairy, often velvety	Macaranga velutina
33b. Petiole glabrous or with some sparse long hairs only; lower leaf surface glabrous or hairy on veins only (not velvety)	34
Choices left: Macaranga angulata; Macaranga bancana; Macaranga hullettii; Macaranga petanostyla; Macaranga velutiniflora
34a. Leaves 28-44 by 22-42 cm, leaf central lobe width 13 cm or more, peltate margin usually more than 5 cm, secondary veins up to 16	35
Choices left: Macaranga petanostyla; Macaranga velutiniflora
34b. Leaves 13-35 by 5-32 cm, leaf central lobe width 13 cm or less, peltate margin usually less than 5 cm, secondary veins up to 22	36
Choices left: Macaranga angulata; Macaranga bancana; Macaranga hullettii
35a. Leaf lateral lobes 4-10 cm long; inflorescences hairy, but not velvety	Macaranga petanostyla
35b. Leaf lateral lobes 2-5 cm long; inflorescences velvety pubescent	Macaranga velutiniflora
36a. Petioles glabrous or with sparse long hairs; leaves shallowly 3-lobed, narrowly ovate, ratio 1.28-2.60, lateral lobes 0.7-2.5 cm, leaf margin with or without glands, secondary veins usually not ending in the margin (looping); staminate bracteoles with fimbriate margin; fruits with long horn-like appendages	Macaranga hullettii
36b. Petioles glabrous; leaves shallowly to deeply 3-5-lobed, broadly ovate, ratio 0.82-1.75, lateral lobes 0.5-17 cm, leaf margin usually with glands, secondary veins ending in the margin; staminate bracteoles with entire margin; fruits with or without long horn-like appendages	37
Choices left: Macaranga angulata; Macaranga bancana
37a. Montane between ca. 800 and 1500 m altitude; leaf base strongly angular to truncate, leaves deeply 3-5-lobed, lateral lobes 5-14 cm, leaf lower surface not or only sparsely gland dotted; fruits with horn like appendages	Macaranga angulata
37b. Only in lowland up to ca. 500 m altitude; leaf base rounded, leaves deeply to shallowly 3-lobed, lateral lobes 0.5-17 cm, leaf lower surface usually numerously gland dotted; fruits without horn like appendages	Macaranga bancana
38a. Leaves peltate and/or lobed	39
Choices left: Macaranga amissa; Macaranga ashtonii; Macaranga conifera; Macaranga costulata; Macaranga depressa; Macaranga didymocarpa; Macaranga endertii: Macaranga gigantea; Macaranga hosei; Macaranga kinabaluensis; Macaranga pachyphylla; Macaranga pearsonii; Macaranga pentaloba; Macaranga pruinosa; Macaranga puberula; Macaranga puncticulata; Macaranga recurvata; Macaranga rostrata; Macaranga sarcocarpa; Macaranga spathicalyx; Macaranga strigosissima; Macaranga tanarius; Macaranga trichocarpa; Mallotus floribundus; Mallotus lackeyi; Mallotus macrostachyus; Mallotus mollissimus; Mallotus paniculatus; Mallotus peltatus; Mallotus subpeltatus; Mallotus tiliifolius
38b. Leaves not peltate and not lobed	88
Choices left: Macaranga amissa; Macaranga auriculata; Macaranga baccaureifolia; Macaranga brevipetiolata; Macaranga conifera; Macaranga costulata: Macaranga fulva; Macaranga kinabaluensis; Macaranga lowii var. lowii; Macaranga lowii var. kostermansii; Macaranga praestans; Macaranga rarispina; Macaranga repando-dentata; Macaranga rostrata; Macaranga strigosissima; Macaranga trichocarpa; Mallotus brachythyrsus; Mallotus dispar; Mallotus eucaustus; Mallotus griffithianus; Mallotus havilandii; Mallotus korthalsii; Mallotus leucodermis; Mallotus macrostachyus; Mallotus miquelianus; Mallotus mollissimus; Mallotus moritzianus; Mallotus muticus; Mallotus paniculatus; Mallotus peltatus; Mallotus penangensis; Mallotus philippensis; Mallotus repandus; Mallotus resinosus; Mallotus stipularis; Mallotus subpeltatus; Mallotus sumatranus; Mallotus tiliifolius; Mallotus wrayi
39a. Leaves lobed	40
Choices left: Macaranga ashtonii; Macaranga depressa; Macaranga gigantea; Macaranga hosei; Macaranga pearsonii; Macaranga pentaloba; Macaranga pruinosa; Macaranga puberula; Macaranga trichocarpa; Mallotus macrostachyus; Mallotus mollissimus; Mallotus paniculatus
39b. Leaves not lobed	52
Choices left: Macaranga amissa; Macaranga conifera; Macaranga costulata; Macaranga didymocarpa; Macaranga endertii; Macaranga kinabaluensis; Macaranga pachyphylla; Macaranga puncticulata; Macaranga recurvata; Macaranga rostrata; Macaranga sarcocarpa; Macaranga spathicalyx; Macaranga strigosissima; Macaranga tanarius; Mallotus floribundus; Mallotus lackeyi; Mallotus macrostachyus; Mallotus mollissimus; Mallotus peltatus; Mallotus subpeltatus; Mallotus tiliifolius
40a. With or without stellate hairs; leaf uppersurface with basal nectary glands (sometimes covered by upcurled basal leaf margin)	41
Choices left: Macaranga trichocarpa; Mallotus macrostachyus; Mallotus mollissimus; Mallotus paniculatus
40b. Simple hairs only; leaf uppersurface without basal nectary glands	44
Choices left: Macaranga ashtonii; Macaranga depressa; Macaranga gigantea; Macaranga hosei; Macaranga pearsonii; Macaranga pentaloba; Macaranga pruinosa; Macaranga puberula
41a. Twigs densely covered by silvery simple hairs; leaf uppersurface hairy all over, usually feeling like sandpaper; inflorescences unbranched	Macaranga trichocarpa
41b. Twigs densely covered by creamish brown stellate hairs; leaf uppersurface glabrous or hairy on veins only, not feeling like sandpaper; inflorescences branched	42
Choices left: Mallotus macrostachyus; Mallotus mollissimus; Mallotus paniculatus
42a. Leaf base wedge shaped, not curled upward, uppersurface with two conspicuous nectary glands, lower surface without domatia, secondary veins not ending in the margin; staminate and pistilate flowers on different plants; fruits with few thick spines	Mallotus paniculatus
42b. Leaf base cordate to rounded, sometimes curled upward, uppersurface with two less conspicuous nectary glands, lower surface with or without domatia, secondary veins ending in the margin; staminate and pistilate flowers sometimes also within one infloresence; fruits woolly and densely covered by short to long spines	43
Choices left: Mallotus macrostachyus; Mallotus mollissimus
43a. Stipules 2-6 mm long; leaf base often curled upward, leaf lower surface with hairy domatia in axils of secondary veins; fruits with short spines between dense wooly indument	Mallotus macrostachyus
43b. Stipules 0.5-1 mm long; leaf base seldomly curled upward, leaf lower surface without hairy domatia; fruits with long spines clearly protruding from dense wooly indument	Mallotus mollissimus
44a. Stipules large, length > 25 mm, green at first, drying papery brownish, persistent	45
Choices left: Macaranga gigantea; Macaranga pentaloba
44b. Stipules small, length < 25 mm, not turning brownish and papery, early-caducous to persistent	46
Choices left: Macaranga ashtonii; Macaranga depressa; Macaranga hosei; Macaranga pearsonii; Macaranga pruinosa; Macaranga puberula
45a. Leaves 3-lobed	Macaranga gigantea
45b. Leaves 5-7-lobed	Macaranga pentaloba
46a. Leaves 5-lobed	Macaranga depressa
46b. Leaves 3-lobed	47
Choices left: Macaranga ashtonii; Macaranga depressa; Macaranga hosei; Macaranga pearsonii; Macaranga pruinosa; Macaranga puberula
47a. Twigs densely hairy, hairs short (< 1 mm long); leaves large, 25-60 by 15-40 cm, peltate margin length > 4 cm	Macaranga ashtonii
47b. Twigs glabrous to densely hairy, hairs short (< 1 mm long) to long (> 1 mm long); leaves small, 7.5-34 by 8-30 cm, peltate margin length < 4.5 cm	48
Choices left: Macaranga depressa; Macaranga hosei; Macaranga pearsonii; Macaranga pruinosa; Macaranga puberula
48a. Twigs glaucous, glabrous; stipules early caducous, ovate, erect; leaf base usually cordate, with some enlarged conical glands along margin	Macaranga pearsonii
48b. Twigs glaucous or not, glabrous to hairy; stipules early-caducous to persistent, triangular to ovate to rounded, spreading; leaf base cordate or not, without enlarged conical glands along margin	49
Choices left: Macaranga depressa; Macaranga hosei; Macaranga pruinosa; Macaranga puberula
49a. Twigs glabrous to hairy, often with long hairs (> 1 mm long), not glaucous; stipules triangular to ovate; leaves peltate, usually longer than wide, length/width-ratio 0.89-1.63, lower leaf surface not or sparsely gland dotted, leaf base (broadly) rounded; staminate bracteoles with entire margin; fruits 5-locular, with horn-like appendages	Macaranga depressa
49b. Twigs glabrous or with short hairs (< 1 mm long) only, glaucous or not; stipules rounded, sometimes apical margin curled up- and inward; leaves peltate or not, wider than long, length/width-ratio 0.62-0.97, lower leaf surface densely gland dotted, leaf base rounded to cordate; staminate bracteoles with fimbriate margin; fruits 2-locular, without horn-like appendages	50
Choices left: Macaranga hosei; Macaranga pruinosa; Macaranga puberula
50a. Twigs glabrous, usually glaucous	Macaranga hosei
50b. Twigs hairy, not glaucous	51
Choices left: Macaranga pruinosa; Macaranga puberula
51a. Lowland usually below 200 m, in swamps; stipules with upcurled tip, forming a sac-like structure; leaves peltate, with up to 11 secondary veins	Macaranga pruinosa
51b. Lowland and montane up to 2000 m, not restricted to swamps; stipules without or only slightly upcurled tip, not forming a sac-like structure; leaves peltate or not, with more than 11 secondary veins	Macaranga puberula
52a. Leaf uppersurface with basal nectary glands, sometimes covered by upcurled basal leaf margin	53
Choices left: Macaranga amissa; Macaranga conifera; Macaranga costulata; Macaranga kinabaluensis; Macaranga rostrata; Macaranga spathicalyx; Macaranga strigosissima; Mallotus floribundus; Mallotus lackeyi; Mallotus macrostachyus; Mallotus mollissimus; Mallotus peltatus; Mallotus tiliifolius
52b. Leaf uppersurface without basal nectary glands, not with upcurled basal leaf margin	66
Choices left: Macaranga amissa; Macaranga conifera; Macaranga didymocarpa; Macaranga endertii; Macaranga kinabaluensis; Macaranga pachyphylla; Macaranga puncticulata; Macaranga recurvata; Macaranga sarcocarpa; Macaranga spathicalyx; Macaranga tanarius; Mallotus subpeltatus
53a. Leaves opposite	54
Choices left: Mallotus peltatus; Mallotus tiliifolius
53b. Leaves alternate	55
Choices left: Macaranga amissa; Macaranga conifera; Macaranga costulata; Macaranga kinabaluensis; Macaranga rostrata; Macaranga spathicalyx; Macaranga strigosissima; Mallotus floribundus; Mallotus lackeyi; Mallotus macrostachyus; Mallotus mollissimus; Mallotus peltatus
54a. Not growing on or near the beach; twigs glabrous to hairy; leaf lower surface usually with domatia; stipule length > 1.5 mm; leaves much longer than wide, length/width-ratio > 2	Mallotus peltatus
54b. Growing on or near the beach; twigs densely hairy; leaf lower surface without domatia; stipule length up to 0.5 mm; leaves only slightly longer than wide, length/width-ratio < 1.5	Mallotus tiliifolius
55a. Hairs (when present) simple, tufted and stellate; lower leaf surface with or without hair tuft domatia; inflorescenses unbranched to branched; fruits 3-locular, with spines	56
Choices left: Mallotus floribundus; Mallotus lackeyi; Mallotus macrostachyus; Mallotus mollissimus; Mallotus peltatus
55b. Hairs (when present) simple only; lower leaf surface with or without roof-like (not hair-tuft) domatia; inflorescenses branched; fruits 2- or > 3-locular, with or without spines	60
Choices left: Macaranga amissa; Macaranga conifera; Macaranga costulata; Macaranga kinabaluensis; Macaranga rostrata; Macaranga spathicalyx; Macaranga strigosissima
56a. Twigs, petioles and leaves glabrous; lower leaf surface with conspicuously large hairy domatia at petiole insertion, domatia along the remainder of the midrib absent or much smaller	Mallotus floribundus
56b. Twigs, petioles and leaves glabrous to densely hairy; lower leaf surface without or with small hairy domatia at petiole insertion that do not differ from domatia along the remainder of the midrib	57
Choices left: Mallotus lackeyi; Mallotus macrostachyus; Mallotus mollissimus; Mallotus peltatus
57a. Twigs and petioles usually glabrous to sparsely hairy, rarely densely hairy; leaves more than twice as long as wide, leaf upper surface not gland dotted	Mallotus peltatus
57b. Twigs and petioles densely hairy; leaves less than twice as long as wide, leaf upper surface gland dotted or not	58
Choices left: Mallotus lackeyi; Mallotus macrostachyus; Mallotus mollissimus
58a. Stipules 5-15 mm long; peltate margin length > 1.8 cm, upper leaf surface gland dotted, leaf apex with long elongated tip	Mallotus lackeyi
58b. Stipules 0.5-6 mm long; peltate margin length < 1.8 cm, upper leaf surface not gland dotted, leaf apex without long elongated tip	59
Choices left: Mallotus macrostachyus; Mallotus mollissimus
59a. Stipules 2-6 mm long; leaf base often curled upward, leaf lower surface with hairy domatia in axils of secondary veins; fruits with short spines between dense wooly indument	Mallotus macrostachyus
59b. Stipules 0.5-1 mm long; leaf base seldomly curled upward, leaf lower surface without hairy domatia; fruits with long spines clearly protruding from dense wooly indument	Mallotus mollissimus
60a. All vegetative parts densely covered with long (> 1 mm) hairs; lower leaf surface with roof-like domatia in secondary vein axils	Macaranga strigosissima
60b. Vegetative parts glabrous or with short (< 1 mm) hairs only; lower leaf surface without domatia	61
Choices left: Macaranga amissa; Macaranga conifera; Macaranga costulata; Macaranga kinabaluensis; Macaranga rostrata; Macaranga spathicalyx
61a. Lower leaf surface not gland dotted, leaf margin strongly serrate	Macaranga rostrata
61b. Lower leaf surface densely gland dotted, leaf margin not or only slightly serrate	62
Choices left: Macaranga amissa; Macaranga conifera; Macaranga costulata; Macaranga kinabaluensis; Macaranga spathicalyx
62a. Twigs densely hairy; lower leaf surface conspicuously glaucous, leaf margin without glands, not serrate, secondary veins not ending in the margin (looping); staminate bracts fimbriate	Macaranga conifera
62b. Twigs glabrous to densely hairy; lower leaf surface not or only slightly glaucous, leaf margin with or without glands, sometimes slightly serrate, secondary veins ending in the margin or not; staminate bracts entire	63
Choices left: Macaranga amissa; Macaranga costulata; Macaranga kinabaluensis; Macaranga spathicalyx
63a. Lowlands only; stipules early caducous; twigs glabrous; leaf base cordate, peltate margin length up to 1.7 cm	Macaranga amissa
63b. Lowlands and montane; twigs glabrous to densely hairy; stipules usually semi-persistent; leaf base not cordate, peltate margin length up to 0.8 cm	64
Choices left: Macaranga costulata; Macaranga kinabaluensis; Macaranga spathicalyx
64a. Stipule width up to 2 mm; leaf secondary veins usually less than 10; fruits large, 4-5 mm wide, with short spines	Macaranga kinabaluensis
64b. Stipule width up to 5 mm; leaf secondary veins usually more than 10; fruits very small, 2-4 mm wide, with or without short spines	65
Choices left: Macaranga costulata; Macaranga spathicalyx
65a. Found throughout Borneo; twigs glabrous to hairy; stipule width 1.5-3 mm; leaf secondary veins usually not ending in the margin; fruit not subtended by enlarged spath-like sepal, not with spines	Macaranga costulata
65b. Only known from Ranau (Sabah); twigs glabrous; stipule width 3-5 mm; leaf secondary veins ending in the margin; fruit subtended by enlarged spath-like sepal, with short spines	Macaranga spathicalyx
66a. Stipules with fimbriate margin; leaf lower surface not gland dotted, not glaucous, leaf length/width-ratio > 2.5; staminate inflorescence with one flower per bract; pistillate inflorescence with one terminal fruit developing	Mallotus subpeltatus
66b. Stipules with entire margin; leaf lower surface gland dotted, glaucous or not, leaf length/width-ratio < 2.5; staminate inflorescence with several flowers per bract; pistillate inflorescence with severl fruits developing	67
Choices left: Macaranga amissa; Macaranga conifera; Macaranga didymocarpa; Macaranga endertii; Macaranga kinabaluensis; Macaranga pachyphylla; Macaranga puncticulata; Macaranga recurvata; Macaranga sarcocarpa; Macaranga spathicalyx; Macaranga tanarius
67a. Lower leaf surface not glaucous	68
Choices left: Macaranga amissa; Macaranga endertii; Macaranga kinabaluensis; Macaranga pachyphylla; Macaranga puncticulata; Macaranga sarcocarpa; Macaranga spathicalyx; Macaranga tanarius
67b. Lower leaf surface glaucous	78
Choices left: Macaranga conifera; Macaranga didymocarpa; Macaranga pachyphylla; Macaranga puncticulata; Macaranga recurvata; Macaranga sarcocarpa; Macaranga tanarius
68a. Leaves strongly bullate	Macaranga sarcocarpa
68b. Leaves not bullate	69
Choices left: Macaranga amissa; Macaranga endertii; Macaranga kinabaluensis; Macaranga pachyphylla; Macaranga puncticulata; Macaranga spathicalyx; Macaranga tanarius
69a. Leaf base clearly cordate	70
Choices left: Macaranga amissa; Macaranga pachyphylla
69b. Leaf base rounded to truncate, not (or only slightly) cordate	71
Choices left: Macaranga endertii; Macaranga kinabaluensis; Macaranga pachyphylla; Macaranga puncticulata; Macaranga spathicalyx; Macaranga tanarius
70a. Possibly throughout Borneo; lowlands only (below ca. 100 m alt.); peltate margin length < 1.9 cm, secondary veins ending in the margin	Macaranga amissa
70b. Only known from Sabah, montane only (above ca. 500 m alt.); peltate margin length > 1.9 cm, secondary veins ending in the margin or not	Macaranga pachyphylla
71a. Peltate margin length < 1.8	72
Choices left: Macaranga endertii; Macaranga kinabaluensis; Macaranga puncticulata; Macaranga spathicalyx
71b. Peltate margin length > 1.8	76
Choices left: Macaranga pachyphylla; Macaranga puncticulata; Macaranga tanarius
72a. Peltate margin length > 0.9	73
Choices left: Macaranga endertii; Macaranga puncticulata
72b. Peltate margin length < 0.9	74
Choices left: Macaranga endertii; Macaranga kinabaluensis; Macaranga spathicalyx
73a. On limestone only, up to ca. 900 m altitude; leaf peltate margin length up to 1.8 cm, secondary veins ending in the margin or not; fruit 2-locular	Macaranga endertii
73b. Restricted to swamps, up to ca. 100 m altitude; leaf peltate margin length up to 3.1 cm; secondary veins ending in the margin; fruit 5-locular	Macaranga puncticulata
74a. Secondary veins not ending in the margin; fruits with spines	Macaranga kinabaluensis
74b. Secondary veins ending in the margin; fruits with or without spines	75
Choices left: Macaranga endertii; Macaranga spathicalyx
75a. Only found on or near limestone; stipules narrowly triangular, 5-11 mm long by 1.5-3 mm wide; leaf secondary vein number 5-11; fruits without spines, subtended by enlarged spath-like bracteole	Macaranga endertii
75b. Not restricted to limestone; stipules ovate, 4-7 mm long by 3-5 mm wide; leaf secondary vein number 11-12; fruits with spines, bracteole not enlarged	Macaranga spathicalyx
76a. Twigs not glaucous; stipules semi-persistent, 1-3 cm long; leaf 12-36 by 7-28 cm, peltate leaf margin up to 9 cm; fruits with few long spines	Macaranga tanarius
76b. Twigs glaucous or not; stipules usually early caducous, 0.4-1.7 cm long; leaf 8.5-20 by 5.5-12.5 cm, peltate leaf margin up to 3.1 cm; fruits without spines	77
Choices left: Macaranga pachyphylla; Macaranga puncticulata
77a. Montane only, between 500 and 1700 m altitude, no preference for swamps; twigs glabrous; stipule width 4-10 mm; leaf secondary veins not ending in the margin	Macaranga pachyphylla
77b. Lowlands only, up to ca. 100 m altitude, usually restricted to swamps; twigs glabrous to hairy; stipule width 2-5 mm; leaf secondary veins ending in the margin	Macaranga puncticulata
78a. Leaves strongly bullate	Macaranga sarcocarpa
78b. Leaves not bullate	79
Choices left: Macaranga conifera; Macaranga didymocarpa; Macaranga pachyphylla; Macaranga puncticulata; Macaranga recurvata; Macaranga tanarius
79a. Twigs and petioles hairy	80
Choices left: Macaranga conifera; Macaranga didymocarpa; Macaranga puncticulata; Macaranga tanarius
79b. Twigs and petioles glabrous	83
Choices left: Macaranga conifera; Macaranga pachyphylla; Macaranga puncticulata; Macaranga recurvata; Macaranga tanarius
80a. Peltate leaf margin < 0.5 cm, secondary veins not ending in the margin	Macaranga conifera
80b. Peltate leaf margin > 0.5 cm, secondary veins usually ending in the margin	81
Choices left: Macaranga didymocarpa; Macaranga puncticulata; Macaranga tanarius
81a. Lowlands and montane up to ca. 1400 m altitude, usually found in severely degraded forest or scrub; stipules semi-persistent, 1-3 cm long by 0.4-1.2 cm wide; leaf 12-36 by 7-28 cm, peltate leaf margin up to 9 cm; fruits with few long spines	Macaranga tanarius
81b. Lowland only, up to ca. 200 m altitude, restricted to swamps or alluvial sites; stipules usually early caducous, 0.4-1.2 cm long by 0.2-0.5 cm wide; leaf 8-20 by 5.5-12.5 cm, peltate leaf margin up to 3.2 cm; fruits without spines	82
Choices left: Macaranga didymocarpa; Macaranga puncticulata
82a. Stipule length up to 6 mm; leaf secondary vein number 8-11, basal pair at almost perpendicular angle with midrib; pistillate inflorescence branched; fruits with 2(-3)-locules	Macaranga didymocarpa
82b. Stipule length up to 12 mm; leaf secondary vein number 5-9, basal pair usually at an angle with the midrib; pistillate inflorescences not branched; fruits with > 3 locules	Macaranga puncticulata
83a. Leaf peltate margin length < 0.7 cm	Macaranga conifera
83b. Leaf peltate margin length > 0.7 cm	84
Choices left: Macaranga pachyphylla; Macaranga puncticulata; Macaranga recurvata; Macaranga tanarius
84a. Leaf peltate margin length > 3.5 cm	85
Choices left: Macaranga recurvata; Macaranga tanarius
84b. Leaf peltate margin length < 3.5 cm	86
Choices left: Macaranga pachyphylla; Macaranga puncticulata; Macaranga tanarius
85a. Stipules early caducous to semi-persistent; leaves 21-55 cm long by 13-44 cm wide, leaf secondary vein number 9-15, lower leaf surface glabrous, densely gland dotted; pistillate inflorescence unbranched, fruits without spines	Macaranga recurvata
85b. Stipules semi-persistent; leaves 12-36 cm long by 7-28 cm wide, leaf secondary vein number 7-10, lower leaf surface sometimes hairy on veins, sparsely to numerously gland dotted; pistillate inflorescence branched, fruits with spines	Macaranga tanarius
86a. Twigs not glaucous; stipules semi-persistent, 1-3 cm long; leaf 12-36 by 7-28 cm; fruits with few long spines	Macaranga tanarius
86b. Twigs glaucous or not; stipules usually early caducous, 0.4-1.7 cm long; leaf 8.5-20 by 5.5-12.5 cm; fruits without spines	87
Choices left: Macaranga pachyphylla; Macaranga puncticulata
87a. Montane only, between 500 and 1700 m altitude, no preference for swamps; twigs glabrous; stipule width 4-10 mm; leaf secondary veins not ending in the margin	Macaranga pachyphylla
87b. Lowlands only, up to ca. 100 m altitude, usually restricted to swamps; twigs glabrous to hairy; stipule width 2-5 mm; leaf secondary veins ending in the margin	Macaranga puncticulata
88a. Leaves opposite (look carefully, some species have very small, scale like opposite leaves, giving them an alternate appearance at first glance)	89
Choices left: Mallotus brachythyrsus; Mallotus dispar; Mallotus eucaustus; Mallotus griffithianus; Mallotus havilandii; Mallotus korthalsii; Mallotus leucodermis; Mallotus miquelianus; Mallotus moritzianus; Mallotus muticus; Mallotus peltatus; Mallotus penangensis; Mallotus resinosus; Mallotus stipularis; Mallotus sumatranus; Mallotus tiliifolius; Mallotus wrayi
88b. Leaves alternate	107
Choices left: Macaranga amissa; Macaranga auriculata; Macaranga baccaureifolia; Macaranga brevipetiolata; Macaranga conifera; Macaranga costulata: Macaranga fulva; Macaranga kinabaluensis; Macaranga lowii var. lowii; Macaranga lowii var. kostermansii; Macaranga praestans; Macaranga rarispina; Macaranga repando-dentata; Macaranga rostrata; Macaranga strigosissima; Macaranga trichocarpa; Mallotus leucodermis; Mallotus macrostachyus; Mallotus mollissimus; Mallotus muticus; Mallotus paniculatus; Mallotus peltatus; Mallotus philippensis; Mallotus repandus; Mallotus subpeltatus
89a. One leaf of each opposite pair scale like; upper leaf surface of non-reduced leaves without basal nectaries	90
Choices left: Mallotus eucaustus; Mallotus griffithianus; Mallotus penangensis; Mallotus stipularis
89b. One leaf of each opposite pair scale or leaf like; upper leaf surface of non-reduced leaves with basal nectaries	93
Choices left: Mallotus brachythyrsus; Mallotus dispar; Mallotus havilandii; Mallotus korthalsii; Mallotus leucodermis; Mallotus miquelianus; Mallotus moritzianus; Mallotus muticus; Mallotus peltatus; Mallotus resinosus; Mallotus sumatranus; Mallotus tiliifolius; Mallotus wrayi
90a. Twigs and petioles densely hairy	91
Choices left: Mallotus eucaustus; Mallotus stipularis
90b. Twigs and petioles glabrous or sparsely hairy	92
Choices left: Mallotus griffithianus; Mallotus penangensis
91a. Twigs and petioles with short hairs (< 1 mm long) only; stipules usually early-caducous, triangular to ovate, 4-10 by 1-3 mm; leaves in one plane (distichous) along twigs	Mallotus eucaustus
91b. Twigs and petioles with short and long hairs (> 1 mm long); stipules usually semi-persistent, narrowly ovate, 8-15 by 2-4 mm; leaves not in one plane along twigs	Mallotus stipularis
92a. Twigs and petioles sometimes sparsely covered with long hairs (ca. 1 mm long), often covered by yellow-red glands with sticky-exudate; stipules early caducous; petiole length 4-9 cm; leaves ovate to elliptic, lower leaf surface without domatia; inflorescences branched; fruit spines with terminal gland	Mallotus griffithianus
92b. Twigs and petioles sometimes sparsely covered with short hairs only (clearly less than 1 mm), not gland covered; stipules early caducous to persistent; petiole length 0.4-5 cm; leaves elliptic to obovate, lower leaf surface with or without hair tuft domatia; inflorescences unbranched; fruit spines without terminal gland	Mallotus penangensis
93a. Upper leaf surface sparsely to densely gland dotted (check with magnifying lens)	94
Choices left: Mallotus brachythyrsus; Mallotus leucodermis; Mallotus muticus; Mallotus sumatranus
93b. Upper leaf surface not gland dotted	97
Choices left: Mallotus dispar; Mallotus havilandii; Mallotus korthalsii; Mallotus miquelianus; Mallotus moritzianus; Mallotus peltatus; Mallotus resinosus; Mallotus tiliifolius; Mallotus wrayi
94a. Shrub up to 2 m tall; stipules semi-persistent, 8-10 mm long; one leaf of opposite pair scale like; petioles of large leaf up to 0.5 cm long; fruits with spines, no long pointed appendages	Mallotus brachythyrsus
94b. Small trees to trees up to 35 m tall; stipules early-caducous, 1-4 mm long; opposite leaves of same shape; petioles up to 12 cm long; fruits without spines, with or without long pointed appendages	95
Choices left: Mallotus leucodermis; Mallotus muticus; Mallotus sumatranus
95a. Small trees up to ca. 15 m tall, restricted to swamps and alluvial sites below 100 m altitude; petioles usually sparsely to densely hairy; leaves often with nectary glands along the whole margin, leaf lower surface glabrous to hairy on veins, with hair-tuft domatia in secondary vein axils; fruits with long spine-like carpels	Mallotus sumatranus
95b. Big trees up to ca. 35 m tall, often on alluvial or swampy soils but not exclusively, found up to ca. 600 m altitude; petioles glabrous; leaves usually only with basal nectary glands; leaf lower surface glabrous, with or without hair-tuft domatia in axils of secondary veins; fruits without spine-like carpels	96
Choices left: Mallotus leucodermis; Mallotus muticus
96a. Petioles up to 13 cm long; hair tuft domatia usually absent, up to 7 secondary veins; pistillate pedicels 6-55 mm long; fruit carpels globose	Mallotus leucodermis
96b. Petioles up to 8.5 cm long; hair tuft domatia usually present, up to 10 secondary veins; pistillate pedicels 1-7 mm long; fruit carpels angular	Mallotus muticus
97a. One leaf of each opposite pair with different shape and size	98
Choices left: Mallotus dispar; Mallotus havilandii; Mallotus miquelianus
97b. Leaves of opposite pairs similar in shape and size or only differing in size	100
Choices left: Mallotus dispar; Mallotus korthalsii; Mallotus moritzianus; Mallotus peltatus; Mallotus resinosus; Mallotus tiliifolius; Mallotus wrayi
98a. Petioles of non reduced leaves > 1 cm; secondary vein numbers of non-reduced leaves 5-9	Mallotus dispar
98b. Petioles of non reduced leaves < 1 cm; secondary vein numbers of non reduced leaves 12-18	99
Choices left: Mallotus havilandii; Mallotus miquelianus
99a. On limestone; whole plant densely hairy; upper leaf surface hairy on veins, with basal nectary glands clearly smaller than 1 mm; inflorescences up to 27 cm long	Mallotus havilandii
99b. On all kind of soils; whole plant glabrous to hairy; upper leaf surface glabrous, with basal nectary glands of ca. 1 mm or larger; inflorescences up to 13.5 cm long, usually much shorter	Mallotus miquelianus
100a. Only growing on or near beaches; length/width-ratio (of non reduced) leaves < 1.5	Mallotus tiliifolius
100b. Not growing on or near beaches; length/width-ratio (of non reduced) leaves > 1.5	101
Choices left: Mallotus dispar; Mallotus korthalsii; Mallotus moritzianus; Mallotus peltatus; Mallotus resinosus; Mallotus wrayi
101a. Leaves penniveined (basal veins shorter than veins higher along the midrib)	102
Choices left: Mallotus dispar; Mallotus peltatus; Mallotus resinosus
101b. Leaves tripliveined (basal veins longer than veins higher along the midrib)	104
Choices left: Mallotus dispar; Mallotus korthalsii; Mallotus moritzianus; Mallotus wrayi
102a. Twigs, petioles and lower leaf surface densely hairy; stipules semi-persistent, 2-8 mm long; secondary veins of non-reduced leaves 5-9	Mallotus dispar
102b. Twigs, petioles and lower leaf surface glabrous to sparsely hairy; stipules early-caducous, 1-4 mm long; secondary veins of non reduced leaves 8-14	103
Choices left: Mallotus peltatus; Mallotus resinosus
103a. Petioles up to 11 cm long; opposite leaves almost of equal size, leaf base usually slightly cordate, leaf basal uppersurface with small (< 1 mm) nectary glands on basal veins, lower surface sparsely gland dotted, with hairy domatia	Mallotus peltatus
103b. Petioles up to 1.5 cm long; opposite leaves clearly differing in size, leaf base not cordate, leaf basal uppersurface with large (ca. 1 mm or more) nectary glands along the midrib on basal veins, lower surface densely gland dotted, without domatia	Mallotus resinosus
104a. Leaf upper surface with 2 nectary glands on basal secondary veins	Mallotus wrayi
104b. Leaf upper surface with 2-many nectary glands on tertiary veins or leaf lamina	105
Choices left: Mallotus dispar; Mallotus korthalsii; Mallotus moritzianus
105a. Second pair of secondary veins arising ca. half way up or higher on the leaf lamina	Mallotus korthalsii
105b. Second pair of secondary veins clearly arising in the lower half of the leaf lamina	106
Choices left: Mallotus dispar; Mallotus moritzianus
106a. Petiole length of non reduced leaf 1-4.5 cm, petiole of small leaf up to 0.5 cm; stipules usually semi-persistent; leaf width 4-8 cm, leaf upper surface usually without apical nectary glands, leaf margin with glands, secondary veins ending in the margin or not	Mallotus dispar
106b. Petiole length of non reduced leaf 2.7-9 cm, petiole of small leaf 1.2-4.5 cm; stipules usually early-caducous; leaf width 6-18 cm, leaf upper surface usually with apical nectary glands, leaf margin without glands, secondary veins not ending in the margin (looping to fading)	Mallotus moritzianus
107a. Leaves penniveined (basal veins clearly shorter than veins higher along the midrib)	108
Choices left: Macaranga auriculata; Macaranga baccaureifolia; Macaranga brevipetiolata; Macaranga costulata: Macaranga fulva; Macaranga lowii var. lowii; Macaranga lowii var. kostermansii; Macaranga praestans; Macaranga rarispina; Macaranga repando-dentata; Macaranga strigosissima; Mallotus peltatus
107b. Leaves tripliveined (basal veins the same length or longer than veins higher along the midrib)	123
Choices left: Macaranga amissa; Macaranga baccaureifolia; Macaranga conifera; Macaranga costulata: Macaranga kinabaluensis; Macaranga rostrata; Macaranga trichocarpa; Mallotus leucodermis; Mallotus macrostachyus; Mallotus mollissimus; Mallotus muticus; Mallotus paniculatus; Mallotus peltatus; Mallotus philippensis; Mallotus repandus; Mallotus subpeltatus
108a. Stipules ovate to triangular (tapering towards apex), not crowded at twig apex	109
Choices left: Macaranga costulata: Mallotus peltatus
108b. Stipules needle-like (short wide base with long pointed apex), crowded at twig apex	110
Choices left: Macaranga auriculata; Macaranga baccaureifolia; Macaranga brevipetiolata: Macaranga fulva; Macaranga lowii var. lowii; Macaranga lowii var. kostermansii; Macaranga praestans; Macaranga rarispina; Macaranga repando-dentata; Macaranga strigosissima
109a. When not glabrous then simple hairs only; stipules usually semi-persistent, 4-12 by 1.5-3 mm; leaf uppersurface with 2-4 basal nectory glands directly next to petiole insertion, lower surface without domatia; inflorescences branched; fruits without spines	Macaranga costulata
109b. When not glabrous than simple, tufted and stellate hairs; stipules early caducous, 1.5-4 by 1-1.5 mm; leaf uppersurface with 2-17 basal nectory glands on basal veins, some distance from petiole insertion, lower surface wit hairy domatia; inflorescences unbranched; fruits with spines	Mallotus peltatus
110a. Twigs glabrous	111
Choices left: Macaranga auriculata; Macaranga lowii var. lowii; Macaranga lowii var. kostermansii; Macaranga praestans; Macaranga rarispina
110b. Twigs hairy	116
Choices left: Macaranga auriculata; Macaranga baccaureifolia; Macaranga brevipetiolata: Macaranga fulva; Macaranga lowii var. lowii; Macaranga repando-dentata; Macaranga strigosissima
111a. Leaf lower surface with domatia	112
Choices left: Macaranga auriculata; Macaranga lowii var. kostermansii; Macaranga praestans
111b. Leaf lower surface without domatia	114
Choices left: Macaranga lowii var. lowii; Macaranga praestans; Macaranga rarispina
112a. Petioles sometimes with some scattered long (> 1 mm long) hairs; stipules 7-11 mm long; petioles 6.5-12 cm long; leaves 19-35 cm long by 6-11 cm wide, secondary veins 14-18	Macaranga praestans
112b. Petioles glabrous or with short (< 1 mm long) hairs; stipules 2-5 mm long; petioles 1-6 cm long; leaves 9-23.5 cm long by 2.5-6.5 cm wide; secondary veins 8-12	113
Choices left: Macaranga auriculata; Macaranga lowii var. kostermansii
113a. Usually some plant parts hairy; upper leaf base with 2-4 inconspicuous nectary glands on basal veins, lower surface not or rarely sparsely gland dotted	Macaranga auriculata
113b. Whole plant glabrous; upper leaf surface with 2 conspicuous nectary glands next petiole, lower surface densely gland dotted	Macaranga lowii var. kostermansii
114a. Petioles with short hairs (< 1 mm long) only	Macaranga lowii var. lowii
114b. Petioles glabrous or with few scattered long (> 1 mm long) hairs	115
Choices left: Macaranga praestans; Macaranga rarispina
115a. Petioles often with few scattered long hairs; leaf base often with 2 conspicuous auricles, upper leaf surface with 2 flat or raised basal nectary glands, secondary veins at almost perpendicular angle with midrib; pistillate inflorescence with large leaf like bracts enclosing the fruit, only one fruit per inflorescence; fruits without spines	Macaranga praestans
115b. Petioles glabrous; leaf base rarely with conspicuous auricles, upper leaf surface with 2-4 flat basal nectary glands, secondary veins at a clear angle with midrib; pistillate inflorescence without large leaf like bracts, several fruits per infloresence; fruits with spines	Macaranga rarispina
116a. Lower leaf surface with domatia (roof-like)	117
Choices left: Macaranga auriculata; Macaranga repando-dentata; Macaranga strigosissima
116b. Lower leaf surface without domatia	119
Choices left: Macaranga baccaureifolia; Macaranga brevipetiolata: Macaranga fulva; Macaranga lowii var. lowii; Macaranga repando-dentata
117a. Indument consisting of short hairs only (< 0.5 mm long)	Macaranga auriculata
117b. Indument with long hairs (> 1 mm long)	118
Choices left: Macaranga repando-dentata; Macaranga strigosissima
118a. Stipules 3-6 mm long; leaves 5.5-16.5 cm long by 3-7 cm wide, leaf upper surface with 2-4 flat basal nectary glands on basal veins, not directly next to petiole insertion, secondary veins ending in the margin	Macaranga repando-dentata
118b. Stipules 5-12 mm long; leaves 14-21 cm long by 4.5-12.5 cm wide, leaf upper surface with 2 usually slightly raised basal nectary glands directly next to petiole insertion, secondary veins not ending in the margin (looping)	Macaranga strigosissima
119a. Twigs and petioles with long hairs (> 1 mm long)	120
Choices left: Macaranga fulva; Macaranga repando-dentata
119b. Twigs and petioles with short hairs only (< 1 mm long)	121
Choices left: Macaranga baccaureifolia; Macaranga brevipetiolata: Macaranga lowii var. lowii
120a. Stipules 6-8 mm long; petiole up to 2.5 cm long; leaves 4.5-8.5 cm long; pistillate inflorescence peduncle < 1 cm	Macaranga fulva
120b. Stipules 3-6 mm long; petiole up to 6 cm long; leaves 5.5-16.5 cm long; pistillate inflorescence peduncle 1.5-3 cm long	Macaranga repando-dentata
121a. Leaf base broadly cordate with 2 inconspicuous basal nectaries some distance from petiole insertion, secondary veins ending in the margin, leaf ratio 1.33-2.00	Macaranga baccaureifolia
121b. Leaves base not or only slightly cordate with 2 conspicuous basal nectaries directly next to petiole, secondary veins not ending in the margin (looping), leaf ratio 1.64-4.00	122
Choices left: Macaranga brevipetiolata: Macaranga lowii var. lowii
122a. Twigs and petioles densely hairy; petiole length 1-4 cm; leaves usually obovate with conspicuously narrowed base, leaf ratio 1.64-2.67, leaf upper surface usually densely hairy on veins	Macaranga brevipetiolata
122b. Twigs and petiole sparsely to densely hairy; petiole length 2.7-8.5 cm; leaves usually ovate to elliptic, leaf ratio 2.13-4.00, leaf upper surface usually glabrous	Macaranga lowii var. lowii
123a. Upper leaf surface completely hairy usually feeling sandpaper like	Macaranga trichocarpa
123b. Upper leaf surface glabrous or only hairy on veins, not feeling sandpaper like	124
Choices left: Macaranga amissa; Macaranga baccaureifolia; Macaranga conifera; Macaranga costulata: Macaranga kinabaluensis; Macaranga rostrata; Mallotus leucodermis; Mallotus macrostachyus; Mallotus mollissimus; Mallotus muticus; Mallotus paniculatus; Mallotus peltatus; Mallotus philippensis; Mallotus repandus; Mallotus subpeltatus
124a. Twigs and petioles with simple, tufted and stellate hairs	125
Choices left: Mallotus macrostachyus; Mallotus mollissimus; Mallotus paniculatus; Mallotus peltatus; Mallotus philippensis; Mallotus repandus
124b. Twigs and petioles glabrous or with simple hairs only	131
Choices left: Macaranga amissa; Macaranga baccaureifolia; Macaranga conifera; Macaranga costulata: Macaranga kinabaluensis; Macaranga rostrata; Mallotus leucodermis; Mallotus muticus; Mallotus peltatus; Mallotus subpeltatus
125a. Leaf uppersurface with 2-several nectary glands on basal veins or leaf lamina, not directly next to petiole insertion	126
Choices left: Mallotus peltatus; Mallotus repandus
125b. Leaf upper surface with 2 nectary glands next petiole insertion, sometimes covered by upcurled basal leaf margin	127
Choices left: Mallotus macrostachyus; Mallotus mollissimus; Mallotus paniculatus; Mallotus philippensis
126a. Shrub to small tree, not with spines on twigs; stipules early caducous, 1.5-4 mm long; leaf ratio 2.27-3.11, secondary vein number 8-14	Mallotus peltatus
126b. Climber, sometimes with few long spines along twigs; stipules semi-persistent, 0.5-1 mm long; leaf ratio 1.11-1.64, secondary vein number 4-5	Mallotus repandus
127a. Leaf length/width-ratio > 1.8	128
Choices left: Mallotus paniculatus; Mallotus philippensis
127b. Leaf length/width-ratio < 1.8	129
Choices left: Mallotus macrostachyus; Mallotus mollissimus; Mallotus paniculatus
128a. Whole plant has a creamish-brown appearance; petioles 3.5-18 cm long; leaf usually tapering towards base, lower leaf surface creamish-brown-white; upper surface often with apical nectary glands near the margin; inflorescences branched; fruits creamish-brown, with spine like appendages	Mallotus paniculatus
128b. Whole plant has a greenish appearance; petioles 5-9 cm long; leaf base usually rounded, lower leaf surface whitish; upper surface without apical nectary glands; inflorescences unbranched; fruits bright red, spines absent	Mallotus philippensis
129a. Leaf base wedge shaped, not curled upward, uppersurface with two conspicuous nectary glands, lower surface without domatia, secondary veins not ending in the margin; staminate and pistilate flowers on different plants; fruits with few thick spines	Mallotus paniculatus
129b. Leaf base cordate to rounded, sometimes curled upward, uppersurface with two less conspicuous nectary glands, lower surface with or without domatia, secondary veins ending in the margin; staminate and pistilate flowers sometimes within one infloresence; fruits woolly and densely covered by short to long spines	130
Choices left: Mallotus macrostachyus; Mallotus mollissimus
130a. Stipules 2-6 mm long; leaf base often curled upward, leaf lower surface with hairy domatia; fruits with short spines between dense wooly indument	Mallotus macrostachyus
130b. Stipules 0.5-1 mm long; leaf base seldomly curled upward, leaf lower surface without hairy domatia; fruits with long spines clearly protruding from dense wooly indument	Mallotus mollissimus
131a. Lower leaf surface conspicuously glaucous	Macaranga conifera
131b. Lower leaf surface not or only faintly glaucous	132
Choices left: Macaranga amissa; Macaranga baccaureifolia; Macaranga costulata: Macaranga kinabaluensis; Macaranga rostrata; Mallotus leucodermis; Mallotus muticus; Mallotus peltatus; Mallotus subpeltatus
132a. Leaf uppersurface densely gland dotted (check carefully with magnifying lens)	133
Choices left: Mallotus leucodermis; Mallotus muticus
132b. Leaf uppersurface not gland dotted	134
Choices left: Macaranga amissa; Macaranga baccaureifolia; Macaranga costulata: Macaranga kinabaluensis; Macaranga rostrata; Mallotus peltatus; Mallotus subpeltatus
133a. Petioles up to 13 cm long; hair tuft domatia usually absent, up to 7 secondary veins; pistillate pedicels 6-55 mm long; fruit carpels globose	Mallotus leucodermis
133b. Petioles up to 8.5 cm long; hair tuft domatia usually present, up to 10 secondary veins; pistillate pedicels 1-7 mm long; fruit carpels angular	Mallotus muticus
134a. Lower leaf surface not gland dotted	135
Choices left: Macaranga rostrata; Mallotus peltatus; Mallotus subpeltatus
134b. Lower leaf surface sparsely to densely gland dotted	137
Choices left: Macaranga amissa; Macaranga baccaureifolia; Macaranga costulata: Macaranga kinabaluensis; Mallotus peltatus
135a. Leaf uppersurface without basal nectary glands	Mallotus subpeltatus
135b. Leaf uppersurface with basal nectary glands	136
Choices left: Macaranga rostrata; Mallotus peltatus
136a. Stipules semi-persistent, 6-9 by 3-4 mm; leaves ovate, leaf ratio 1.18-2.07, lower surface without domatia; inflorescences branched	Macaranga rostrata
136b. Stipules early caducous, 1.5-4 by 1-1.5 mm; leaves elliptic to obovate, leaf ratio 2.27-3.11, lower surface with hair tuft domatia; inflorescences unbranched	Mallotus peltatus
137a. Stipules early caducous, up to 4 mm long; lower leaf surface usually sparsely gland dotted, with conspicuous hair tuft domatia; fruits 3-locular	Mallotus peltatus
137b. Stipules early caducous to persistent, 2-13 mm long; lower leaf surface densely gland dotted, without domatia; fruits 2-locular	138
Choices left: Macaranga amissa; Macaranga baccaureifolia; Macaranga costulata: Macaranga kinabaluensis
138a. Stipules crowded at twig apex, needle like; leaves ovate to elliptic; staminate inflorescence not branched; pistillate inflorescence with one fruit enclosed by large bracts; fruit spiny	Macaranga baccaureifolia
138b. Stipules not crowded at twig apex, ovate to triangular; leaves usually ovate; staminate inflorescence branched; pistillate inflorescence with several fruits, not enclosed by large bracts; fruit spiny or not	139
Choices left: Macaranga amissa; Macaranga costulata: Macaranga kinabaluensis
139a. Lowlands only (up to ca. 100 m altitude), restricted to swampy places; twigs and petioles glabrous; stipules early caducous, 6-13 mm long by 2.5-6 mm wide; leaf base usually broadly cordate, leaf upper surface with basal nectary glands some distance from petiole insertion, secondary veins ending in the margin; fruits 9-10 mm diameter	Macaranga amissa
139b. Lowland to montane, not restricted to swamps; twigs and petioles usually hairy; stipules usually semi-persistent, 2-12 mm long by 1.5-3 mm wide; leaf base not or only slightly cordate, leaf upper surface with basal nectary glands directly next to petiole insertion, secondary veins usually not ending in the margin (looping); fruits 2-5 mm diameter	140
Choices left: Macaranga costulata: Macaranga kinabaluensis
140a. Stipule length up to 12 mm; leaf secondary vein number 9-17; bracteoles up to 5 mm long; fruit without spines	Macaranga costulata
140b. Stipule length up to 7 mm; leaf secondary vein number 6-10; bracteoles up to 10 mm; fruit with spines	Macaranga kinabaluensis