AporosaNG

Key to the Species of New Guinea (and the Solomon Islands)

Introduction

This key has three parts, because the identification of the New Guinean species is very difficult. Part one (spot characters) lists a few characters characteristic for some species. The second key is only for the hermaphroditic species, and the last key for all New Guinean species.

List of spot-characters

Ovary and fruit lamellate (click picture)

31. A. lamellata

Leaf beneath scattered with numerous black disc-like glands, often found in swampy area

33. A. ledermanniana

Petiole > 30 mm long, leaves large, 17–34 cm long, shiny

50. A. praegrandifolia

Petiole 3–8 mm long, often entirely pulvinate

10. A. brevicaudata

48. A. parvula

57. A. sclerophylla

Hermaphrodites

1a.	Ovary 2-locular (sometimes 2- and 3-locular). Fruit (narrowly) ovoid to fusiform. — Papua New Guinea	2
1b.	Ovary 3-locular. Fruit (sub)globose. — Bougainville	28. A. heterodoxa
2a.	Stipules present in young stages, oblique to slightly falcate. Leaf: apex acute to acuminate. Stamens 2 or 3, not exserted; ovary narrowly ovoid. Fruits narrowly ellipsoid to fusiform, 16–19 by 6–9 mm	3
2b.	Stipules early caducous. Leaf: apex acuminate to cuspidate. Stamens 4 (or 5), exserted; ovary ovoid. Fruits ellipsoid to ovoid, 8–13 by 8–13 mm	27. A. hermaphrodita
3a.	Petiole 3–8 mm long, often entirely pulvinate. Sepals narrowly ovate; stamens 1.2–2.5 mm long	10. A. brevicaudata
3b.	Petiole 11–26 mm long, pulvinate at base and apex, lower pulvinus often indistinct. Sepals ovate; stamens (?young) 0.5–0.8 mm long	18. A. egregia

Key to all New Guinean species

1a.

Nerves 5–10 pairs

1b.

Nerves 10–17 pairs

2a.

Petioles 3–8 mm long, often entirely pulvinate

2b.

Petioles 5–28 mm long, pulvinate at base and apex

3a.

Staminate inflorescences (as far as known) 5–10 mm long; anthers 0.4–0.5 mm long. Bracts of staminate and pistillate inflorescences inconspicuous, 0.5–1.5 mm long. Ovary and fruit ovoid to ellipsoid. Fruits 8–10 mm long, not beaked. Petioles 2–5 mm long. Leaves 2.5–5 by 1–2 cm

3b.

Staminate inflorescences 11–26 mm long; anthers 0.6–0.8 mm long. Bracts of staminate and pistillate inflorescences conspicuous, 1.3–2.5 mm long. Ovary and fruit narrowly ovoid to narrowly ellipsoid. Fruits 16–19 mm long, beaked. Petioles 3–8 mm long. Leaves 3–9.5 by 1–4 cm. — Pistillate specimens sometimes with stamens

10. A. brevicaudata

4a.

Stipules mostly early caducous. Leaves elliptic to obovate, apex acute to acuminate; nerves 5–7 pairs

48. A. parvula

4b.

Stipules mostly shortly persistent. Leaves (narrowly) elliptic, apex acuminate to cuspidate; nerves 7–10 pairs

57. A. sclerophylla

5a.

Branchlets densely to sparsely tomentose. Leaves above at least on midrib (sparsely) tomentose, beneath (sparsely) tomentose

5b.

Branchlets sparsely puberulous to glabrous. Leaves glabrous or only sparsely puberulous beneath

6a.

Nerves 7–10 pairs. Ovary often 2- or 3-locular. Staminate inflorescences 7–15 mm long, 1–2 mm diameter. Pistillate pedicel 0.5–1 mm long. Fruiting pedicel 1–4 mm long

6b.

Nerves 9–15 pairs. Ovary mostly 3-locular, seldom 4-locular. Staminate inflorescences 9–92 mm long, 1.5–5 mm diameter. Pistillate pedicel 0.5–4 mm long. Fruiting pedicel 3–9 mm long

7a.

Leaves above only midrib tomentose. Pistillate pedicel and ovary tomentose. Fruits ellipsoid, very sparsely puberulous; column at base hairy. — Altitude low to 600 m

2. A. annulata

7b.

Leaves above midrib and lamina (sparsely) tomentose. Pistillate pedicel and ovary densely tomentose. Fruits ovoid, patchy tomentose; column glabrous. — Altitude 1300–1700 m

54. A. reticulata

8a.

Dried leaf: dots distinct; disc-like glands absent or few scattered along the margin; if regularly scattered along the margin then leaf apex cuspidate to caudate. Staminate inflorescences with distinctly interrupted glomerules throughout the rachis or glomerules continuously set, indistinct. Pistillate flowers and fruits 3-locular, fruits ovoid to globose, sometimes slightly lobed (A. nigropunctata), or 2-locular and (broadly) ellipsoid (A. misimana), or hermaphroditic flowers and fruits with withered stamens

8b.

Dried leaf: dots indistinct; disc-like glands many scattered along the margin or over the lamina or at base only; if indistinct or only few scattered along the margin then inflorescences subglabrous. Staminate inflorescences (as far as known) with glomerules at base interrupted at 0.5–1 mm, continuous apically. Pistillate flowers and fruits 2-locular (A. egregia), narrowly ovoid or narrowly ellipsoid to fusiform, or 3-locular, ovoid to globose, not lobed

9a.

Inflorescences with hermaphroditic flowers; fruits with withered stamens. — Altitude > 1000 m

9b.

Staminate and pistillate inflorescences separate; stamens never present in pistillate flowers or fruits. — Altitude up to 600 m

10a.

Ovary mostly 2-locular (sometimes 2- and 3-locular); stigmas 1.5–2.5 mm long; pedicel 1–3.5 mm long. Fruit ellipsoid to (narrowly) ovoid; pedicel 2–7 mm long; pericarp 0.3–0.5 mm thick. — Papua New Guinea

27. A. hermaphrodita

10b.

Ovary mostly 3-locular (sometimes 2-locular); stigmas 0.8–1.2 mm long; pedicel 0.5–1 mm long. Fruit (sub)globose; pedicel 3–5 mm long; pericarp 0.5–1 mm thick. Fruit. — Bougainville

28. A. heterodoxa

11a.

Leaf: apex acuminate to cuspidate; dots rather laxly set; disc-like glands occasionally present along the margin. Branchlets, petiole, and midrib beneath glabrous or sparsely puberulous. Staminate inflorescences continuous (click picture). Pistillate flowers and fruits (as far as known) subsessile, very sparsely puberulous to glabrous, mostly 2-locular, seldom 3-locular. Fruits not lobed

11b.

Leaf: apex cuspidate to caudate; dots densely set; disc-like glands regularly present along the margin. Branchlets, petiole, and midrib beneath (sparsely) tomentose. Staminate inflorescences interrupted. Pistillate flowers and fruits pedicelled, sparsely sericeous to sparsely puberulous, 3-locular. Fruits slightly lobed

44. A. nigropunctata

12a.

Branchlets and leaves completely glabrous. Stipules early caducous. Leaf: base cuneate to attenuate; dots grey. Staminate inflorescences 0.5–1 mm diameter. Pistillate flowers and fruits unknown. — North Papua New Guinea

34. A. leptochrysandra

12b.

Branchlets and midrib of leaves sparsely puberulous. Stipules present in young stages, (slightly) falcate. Leaf: base cordate to cuneate; dots black. Staminate inflorescences 1–1.5 mm diameter. Pistillate flowers and fruits ovoid, subsessile. — Eastern Papuan Islands

41. A. misimana

13a.

Leaf: disc-like glands regularly present, along the margin or scattered over the lamina or at base only. Inflorescences sparsely tomentose to puberulous. Staminate inflorescences distinctly (1.5–9 mm) spaced at base (click picture). Pistillate flower (as far as known) mostly 3-locular, seldom 2-locular; ovary ovoid. Fruit (as far as known) ovoid to subglobose, 8–12 mm long

13b.

Leaf: disc-like glands few, occasionally present along the margin. Inflorescences subglabrous. Staminate inflorescences slightly (0.5–1 mm) spaced at base (click picture). Pistillate flower 2-locular; ovary narrowly ovoid. Fruit narrowly ellipsoid to fusiform, 16–19 mm long

8. A. egregia

14a.

Leaf: disc-like glands scattered within the marginal vein arches, throughout the lamina or at the base only

14b.

Leaf: disc-like glands scattered along the margin

15a.

Stipules shortly persistent, narrowly ovate, oblique. Leaf: disc-like glands scattered near base only; base cordate to obtuse. — Staminate inflorescences: glomerules subglobose, spaced at base, continuous apically. Pistillate flower: pedicel either 3–6 or 0–0.5 mm long; ovary sericeous. Fruit beaked, ovoid

13. A. carrii

15b.

Stipules early caducous. Leaf: disc-like glands scattered over the lamina; base obtuse to cuneate. — Staminate inflorescences unknown. Pistillate flower: pedicel 1–1.5 mm long; ovary sparsely puberulous. Fruit not beaked, possibly globose

69. A. spec. A

16a.

Leaves 6.5–11 by 2.5–3.5 cm; nerves 5–7 pairs. Inflorescences axillary to just below the leaves. — Staminate inflorescences (ex descr.) 20–40 mm long, stamens hardly exserted, c. 1 mm long. Pistillate inflorescences 0.3–0.5 mm diameter. Flower: pedicel 0.5–1.5 mm long; ovary 3-locular, glabrous; stigmas slightly recurved, 1–1.5 mm. — Altitude 1000–2200 m

21. A. flexuosa

16b.

Leaves 12–18.5 by 4–6.5 cm; nerves 7–11 pairs. Inflorescences mostly on the trunk. — Altitude 250–300 m. Staminate inflorescences 19–69 mm long, stamens exserted, 1.2–2 mm long. Pistillate inflorescences and flowers unknown

70. A. spec. B

17a.

Leaf: disc-like glands absent or present along the margin or only near base

17b.

Leaves beneath with scattered black disc-like glands. — Staminate inflorescences: glomerules interrupted, stamens exserted. Pistillate inflorescences: flowers laxly set at base of rachis, clustered at apex. Ovary and fruit 2- or 3-locular, sparsely light hairy. Mostly in swamps or swampy areas

33. A. ledermanniana

18a.

Leaves subglabrous or only beneath on midrib sparsely tomentose; disc-like glands mostly many, sometimes only few, along the margin. Branchlets sparsely tomentose to subglabrous

18b.

Leaves above glabrous or on nerves and lamina sparsely to densely tomentose, beneath sparsely to densely tomentose; disc-like glands absent or few near the base. Branchlets (densely) tomentose, seldom sparsely so

19a.

Petiole 9–42 mm long. Leaves 12–34 by 4–13 cm; apex acuminate; disc-like glands mostly many, along the margin (click picture); dots indistinct or absent. Staminate inflorescences 14–69 mm long

19b.

Petiole 3–8 mm long. Leaves 6.5–14 by 1.5–4.5 cm; apex cuspidate to caudate; disc-like glands occasionally few, along the margin (click picture); dots distinct. Staminate inflorescences up to 8 mm long. — Pistillate inflorescences c. 6 mm long; pistillate flower: pedicel minute; stigma 1–1.5 mm long. Fruiting pedicel < 0.5 mm long

36. A. longicaudata

20a.

Leaves rather leathery, shiny when dry; 17–34 by 4–13 cm. Petiole 11–42 mm long. Inflorescences axillary or on the branches; peduncle 0–3 mm long. — Fruits long pedicelled (but pistillate flowers not!)

20b.

Leaves papery, dull when dry; 12–18 by 4–6.5 cm. Petiole 9–16 mm long. Inflorescences (as far as known) mostly on the trunk, occasionally some axillary; peduncle 4–17 mm long. — Fruits and pistillate flowers unknown

70. A. spec. B

21a.

Petiole 11–27 mm long. Staminate inflorescences 0.7–1.5 mm diam., sparsely puberulous; glomerules globose, 1–1.5 by 1–1.5 mm, spaced at 1–5 mm along the rachis; bracts inconspicuous, sparsely puberulous. Pistillate inflorescences 13–24 mm long, (sparsely) puberulous, flowers laxly set, pedicel 1–3 mm long. Fruiting pedicel 2–11 mm long; fruit ovoid

32. A. laxiflora

21b.

Petiole 18–42 mm long. Staminate inflorescences 3–3.5 mm diam., (densely) tomentose; glomerules ellipsoid, 3–4 by 2–3 mm, spaced at 0.5–2 mm at base, continuous apically; bracts conspicuous, tomentose. Pistillate inflorescences 2–8 mm long, tomentose, flowers densely set, sessile. Fruiting pedicel 9–17 mm long; fruit globose

50. A. praegrandifolia

22a.

Indumentum (densely) tomentose. Leaves not or very slightly bullate; margin (lowly) undulate to (lowly) glandular-crenate, not recurved. Stipules persistent or not. Staminate inflorescences (as far as known) 9–92 mm long. Pistillate inflorescences (as far as known) 5–78 mm long, flowers subsessile to pedicelled

22b.

Indumentum (densely) hirsute. Leaves slightly bullate; margin (lowly) glandular-dentate, recurved. Stipules persistent. Staminate inflorescences (young) 5–8 mm long. Pistillate inflorescences 3–5 mm long, flowers sessile

16. A. decipiens

23a.

Nerves 11–15 pairs

23b.

Nerves 9–12 pairs

24a.

Leaves (sparsely) tomentose above, glabrescent; disc-like glands occasionally present at base or along margin, sometimes indistinct. Ovary lowly lobed or not, pedicel 0.5–1.5 mm long. Fruit lobed or not, 10–19 mm broad. — Staminate inflorescences (densely) tomentose, slightly interrupted at base only or almost continuous. Petiole 5–27 mm long. Leaves 7–31 by 3–11 cm

24b.

Leaves glabrous above; disc-like glands absent. Ovary lamellate (click picture), subsessile. Fruit lamellate (click picture), 18–23 mm broad. — Staminate inflorescences unknown. Petiole 11–37 mm long. Leaves 20–32.5 by 6.5–10 cm

The three species in leads 24 and 25, A. lamellata, A. brassii, and A. papuana, are almost only separable in fruit.

31. A. lamellata

25a.

Leaves sparsely tomentose above, glabrescent; dots irregularly set, grey, fading; disc-like glands occasionally present near base only. Inflorescences axillary to just below the leaves, or on the branches. Staminate inflorescences: glomerules spaced at 1–5 mm at base of rachis, or almost continuous throughout. Pistillate flowers: stigma slightly raised, straight. Fruiting pedicel 3–7 mm long; fruits ovoid, 10–16 by 10–16 mm, not lobed; pericarp 1.5–3 mm thick

9. A. brassii

25b.

Leaves (sparsely) tomentose above; dots indistinct; disc-like glands occasionally present along margin. Inflorescences axillary to just below the leaves, not on the branches. Staminate inflorescences: glomerules approximately continuously spaced. Pistillate flowers: stigma raised, recurved. Fruiting pedicel 2–5 mm long; fruits (broadly) ovoid, 12–18 by 12–19 mm, slightly lobed; pericarp 1–2 mm thick

47. A. papuana

26a.

Leaf: marginal glands regular, distinct; disc-like glands scattered at base of leaf, sometimes indistinct. Staminate inflorescences with glomerules usually at least at base (slightly) spaced, 9–69 mm long. — Pistillate inflorescences densely to sparsely tomentose, flowers rather densely or rather laxly set along the rachis

26b.

Leaf: marginal glands few, indistinct; disc-like glands absent. Staminate inflorescences with continuously set indistinct glomerules, 27–92 mm long. — Pistillate inflorescences unknown

71. A. spec. C

27a.

Staminate inflorescences up to 2–5 mm diam.; glomerules mostly only spaced at base to almost continuous

27b.

Staminate inflorescences up to 1.5–2.5 mm diam.; glomerules mostly interrupted throughout

28a.

Indumentum densely tomentose. Petiole 6–16 mm long. Leaves 11–21 by 4–9.5 cm; base cordate to rounded; dots irregularly set, fading; disc-like glands occasionally present near base, indistinct. Inflorescences often on the branches. Staminate inflorescences 16–69 mm long, 2–4 mm diam., densely tomentose. Stigma slightly raised, straight. Fruits ovoid, beaked; fruiting pedicel 3–7 mm long

9. A. brassii

28b.

Indumentum tomentose. Petiole 5–28 mm long. Leaves 9–26 by 3–12 cm; base rounded to cuneate; dots densely set, fading; disc-like glands scattered mostly at base, often distinct. Inflorescences axillary or in the axils of fallen leaves. Staminate inflorescences 9–29 mm long, 3–5 mm diam., tomentose. Stigma raised, (slightly) recurved. Fruits ovoid to subglobose, not beaked; fruiting pedicel 4–9 mm long

67. A. vagans

29a.

Indumentum sparsely tomentose. Leaf: nervation not sunken. Staminate inflorescences up to 29 mm long. — Fruits (sub)globose, long pedicelled

67. A. vagans

29b.

Indumentum tomentose. Leaf: nervation often sunken. Staminate inflorescences up to 47 mm long. — Fruits unknown

72. A. spec. D