| 1 | Leaves 1-foliolate (or rarely 3-foliolate). |
| 1' | Leaves 1-4-pinnate. |
| 2 | Flowers 4-merous. Fruit usually 4-seeded. Philippines. |
| 2' | Flowers 5-merous. Fruits usually 6-seeded (sometimes less by abortion). Not in Philippines. |
| 3 | Leaflets obovate, pair of foliar outgrowths (rarely seen as reduced leaflets) above the stipular wing |
| 3' | Leaflets elliptic or ovate, foliar outgrowths absent. |
| 4 | Seeds complexely ruminate (Fig. 4a). Leaflets up to 22 by 9 cm |
| 4' | Seeds simply ruminate (compare Fig. 4d-e). Leaflets usually over 22 by 9 cm. |
| 5 | Corolla tube + staminodial lobes less than 3 mm long, lower free part of staminodial tube up to ½ mm. Fruit usually up to 10 mm ø Malaya, Sumatra, Java |
| 5' | Corolla tube + staminodial lobes over 3 mm long, lower free part of staminodial tube over ½ mm. Fruit usually over 10 mm ø New Guinea. |
| 6 | Corolla tube + staminodial lobes less than 4½ mm. Leaflet base subauriculate. |
| 6' | Corolla tube + staminodial lobes over 4½ mm. Leaflet base cuneate to truncate |
| 7 | Stipule a narrow wing, somewhat persistent, scar long and thin. Compare Fig. 2(4, 7, 13). |
| 7' | Stipule obovate, caducous, leaving a broad scar. Compare Fig. 3(21, 23, 24). |
| 8 | Flowers 4-merous. Fruits usually 4-seeded (if 6-seeded then fruit over 20 mm ø). |
| 8' | Flowers 5-merous. Fruit usually 6-seeded. |
| 9 | Staminodial tube over 5 mm long. Fruits over 20 mm ø, 6-seeded. New Guinea and Solomon Is. |
| 9' | Staminodial tube less than 5 mm. Fruit less than 20 mm ø, 4-seeded. Philippines. |
| 10 | Lobes of staminodial tube strongly bifid. Inflorescences condensed, erect. Flowers orange-yellow. Mainland of New Guinea |
| 10' | Lobes of staminodial tube retuse. Inflorescences lax, pendulous. Flowers white. Solomon Is. |
| 11 | Style over 3 mm long; staminodial tube 4-5 mm long; filaments over 2 mm. Inflorescence generally condensed, 3-branched, peduncle usually up to 3 cm. Young parts sometimes fulvously pubescent. Leaflets usually elliptic to elliptic-lanceolate, over 7 cm wide; ultimate venation distinct. Rumination outline in seed simple to slightly branched |
| 11' | Style up to 2 mm long; staminodial tube 2½-4 mm; filaments up to 2 mm. Inflorescence generally lax and multi-branched, peduncle over 3 cm. Young parts never fulvous pubescent. Leaflets generally ovate to ovate-lanceolate and less than 7 cm wide; ultimate venation indistinct. Rumination outline in seed complexly reticulate |
| 12 | Stems spiny. |
| 12' | Stems not spiny or information lacking. |
| 13 | Leaves 1-pinnate |
| 13' | Leaves 2- or 3-4-pinnate |
| 14 | Corolla tube + staminodial lobes 6 mm or more and staminodial tube over 5¼ mm long. Fruit where known over 20 mm ø. New Guinea and Solomon Is. |
| 14' | Corolla tube + staminodial lobes up to 6 mm or staminodial tube less than 5¼ mm long. Fruit less than 20 mm ø. Not in New Guinea except for L. gonioptera and L. aculeata. |
| 15 | Leaves 3- or 4-pinnate, leaflets up to 14 by 5 cm. Flowers pink. Mainland New Guinea |
| 15' | Leaves 1- or 2-pinnate, leaflets mostly over 14 by 5 cm. Flowers not pink. |
| 16 | Lobes of staminodial tube strongly bifid. Inflorescence condensed, erect. Flowers orange-yellow. Mainland New Guinea |
| 16' | Lobes of staminodial tube retuse. Inflorescence lax, pendulous. Bismarck Archipelago and Solomon Is. |
| 17 | Inflorescence usually glabrous. Corolla tube + staminodial lobes 8-11 mm, filaments 5-7 mm, anthers 3-5 mm. Young parts not fulvously pubescent. Bismarck Archipelago |
| 17' | Inflorescence usually fulvously pubescent. Corolla tube + staminodial lobes 6-8 mm, filaments 3 mm, anthers 2 mm. Young parts usually fulvously pubescent. Solomon Is. |
| 18 | Leaves 1-pinnate. |
| 18' | Leaves 2- to 4-pinnate. |
| 19 | Corolla tube + staminodial lobes up to 2½ mm, staminodial tube up to 1½ mm long. Small shrubs with creeping rootstock |
| 19' | Corolla tube + staminodial lobes over 2½ mm; staminodial tube over 1½ mm. Shrubs or trees. |
| 20 | Flowers red |
| 20' | Flowers green or white. |
| 21 | Calyx ± inflated around the corolla tube, completely enclosing the corolla in the bud. Corolla tube + staminodial lobes over 5 mm, staminodial tube over 4 mm. Fruit c. 20 mm ø |
| 21' | Calyx not enclosing the corolla in the bud, not so inflated. Corolla tube + staminodial lobes less than 5 mm, staminodial tube less than 4 mm. Fruit usually less than 15 mm (rarely to 20 mm) ø. |
| 22 | Leaflet base subauriculate. Stem smooth. Staminodial tube up to 3 mm long, lower free part up to 1¼ mm long. New Guinea |
| 22' | Leaflet base rounded to cuneate. Stem spiny. Staminodial tube 3-3½ mm long, lower free part over 1¼ mm long. Scattered throughout Malesia, except Malaya, very rare in W. New Guinea |
| 23 | Staminodial tube up to 2¼ mm long. Stipules up to 6 cm long. Petiole generally less than 10 cm. |
| 24 | Corolla tube + staminodial lobes over 3¼ mm, sinuses of staminodial tube shallow. Flowers greenish white. Fruit greyish blue. Stems and ultimate branches spiny. |
| 24' | Corolla tube + staminodial lobes at least 2¼ mm long, sinuses of staminodial tube shallow. Flowers red. Fruit red. Stems and branches not spiny |
| 24'' | Staminodial tube at least 2½ mm long. Stipules usually over 6 cm long. Petiole generally over 10 cm |
| 25 | Flowers 4-merous. Fruits usually 4-seeded. Philippines |
| 25' | Flowers 5-merous. Fruits usually 6-seeded. |
| 26 | Leaves 1-pinnate. |
| 26' | Leaves 2-4-pinnate. |
| 27 | Flowers red to orange-yellow |
| 27' | Flowers greenish white. |
| 28 | Corolla tube + staminodial lobes over 4 mm, staminodial tube over 2¾ mm. Fruit c. 20 mm ø. |
| 28' | Corolla tube + staminodial lobes less than 4 mm, staminodial tube less than 2¾ mm. Fruit up to 15 mm ø |
| 29 | Sinuses of staminodial tube deep, c. 1 mm. Leaflets generally over 30 cm long. |
| 29' | Sinuses of staminodial tube shallow to ½ mm. Leaflets generally but not exclusively up to 30 cm long |
| 30 | Corolla tube + staminodial lobes over 4 mm, staminodial tube over 3 mm. Fruit at least 20 mm ø. New Guinea. |
| 30' | Corolla tube + staminodial lobes less than 4 mm, staminodial tube less than 3 mm. Fruit less than 20 mm ø. |
| 31 | Sinuses of staminodial tube deep, c. 1 mm. Leaflets generally over 30 by 9 cm, nerves usually over 10 pairs. Stipular scar generally over 4 cm long |
| 31' | Sinuses of staminodial tube shallow, less than ½ mm. Leaflets generally less than 30 by 9 cm, nerves generally less than 10 pairs. Stipular scar up to 4 cm long. |
| 32 | Inflorescence and leaflets with large, discoidal, pallid brown pearl glands. Bracts of inflorescence large, conspicuous, up to 8 by 5 mm |
| 32' | Pearl glands inconspicuous, or absent. Bracts smaller, inconspicuous. |
| 33 | Petiole, rachis, and costa with crisped fluted emergences. Leaflets large, 30-40 by 10-17 cm. Celebes |
| 33' | Emergences absent. Leaflets usually, but not exclusively, smaller. |
| 34 | Flowers greenish-white |
| 34' | Flowers red to orange-yellow. |
| 35 | Corolla tube + staminodial lobes generally over 3 mm, staminodial tube over 2 mm, sinuses of staminodial tube shallow |
| 35' | Corolla tube + staminodial lobes up to 3 mm, staminodial tube less than 2 mm, sinuses of staminodial tube deep |
