Tetrastigma

Kochaiphat, Phongsakorn, Trias-Blasi, Anna & Pornpongrungrueng, Pimwadee, 2014, A new combination and new records of Tetrastigma (Vitaceae) from Thailand, Phytotaxa 183 (4), pp. 272-278 : 272-273

Key to the species of Tetrastigma in Thailand

1. Tendrils 5–7 palmately branched; leaves palmately 3-foliolate .............................................................................. 26. T. triphyllum

- Tendrils simple or bifurcate; leaves simple, palmately 3‒5(‒7)-foliolate or pedately 5‒7(‒9)-foliolate ........................................ 2.

2. Inflorescences on old stems (cauliflorous plants), more than 5 inflorescences per nodes ...................................... 6. T. cauliflorum

- Inflorescences on young branches, 1‒3 inflorescences per nodes .................................................................................................. 3.

3. Young branches with 4‒5 sharp ridges ............................................................................................................. 21. T. quadrangulum

- Young branches round or nearly round ........................................................................................................................................... 4.

4. Leaves palmately 3‒5(‒7)-foliolate or mixed with simple leaves or all leaves simple ................................................................... 5.

- Leaves pedately 5‒7(‒9)-foliolate rarely mixed with 3-foliolate .................................................................................................. 16.

5. Stems verrucose or with corky protuberances ................................................................................................................................. 6.

- Stems smooth, pubescent or with flaky cork ................................................................................................................................... 8.

6. Stems with corky protuberances; leaves ovate to elliptic; stigma distinctly 4-lobed ...................................................................... 7.

- Stems verrucose; leaves lanceolate; stigma peltate ................................................................................................. 12. T. harmandii

7. Leaves fleshly; stigma cruciform; berries ellipsoid when dry .................................................................................... 7. T. cruciatum

- Leaves coriaceous or papyraceous; stigma pointed lobes; berries pyriform when dry ................................................. 2. T. assimile

8. Shrubs, creeping, erect or decumbent .............................................................................................................................................. 9.

- Lianas ............................................................................................................................................................................................ 10.

9. Leaves simple or mixed with palmately 3(‒5)-foliolate; pedicel 0.4‒0.6 cm long ........................................... 4. T. bambusetorum

- Leaves palmately 3-foliolate; pedicel 0.8–1.2 cm long ............................................................................................ 1. T. apiculatum

10. Leaflets glabrous .......................................................................................................................................................................... 11.

- Leaflets pubescent or hirsute at least along the midrib on lower leaf surface ............................................................................... 15.

11. Female flower disc conspicuous, thick and adnate to lower part of ovary .................................................................................... 12.

- Female flower disc inconspicuous ................................................................................................................................................. 14. 12. Terminal leaflets broadly elliptic to rhombic; berries pyriform when dry ........................................................... 17. T. pedunculare

- Terminal leaflets elliptic, ovate or lanceolate; berries ellipsoid when dry .................................................................................... 13.

13. Leaves coriaceous or subcoriaceous ....................................................................................................................... 10. T. erubescens

- Leaves papyraceous ........................................................................................................................................................ 9. T. dubium

14. Leaflets broadly ovate or broadly elliptic, apex caudate .................................................................................. 5. T. campylocarpum

- Leaflets lanceolate, apex attenuate .......................................................................................................................... 19. T. planicaule

15. Ovary brownish hirsute; leaves palmately 5-foliolate .............................................................................................. 15. T. obovatum

- Ovary glabrous; leaves palmately 3-foliolate ................................................................................................................. 9. T. dubium

16. Leaves 5-foliolate, rarely mixed with 7-foliolate .......................................................................................................................... 17.

- Leaves 7(‒9)-foliolate, rarely mixed with 5-foliolate .................................................................................................................... 27.

17. Branches glabrous; leaflets glabrous on both surfaces .................................................................................................................. 18.

- Branches more or less pubescent; leaflets pubescent at least along the midvein on lower leaf surface ....................................... 24.

18. Secondary branches of peduncle 2 ............................................................................................................................ 3. T. baenzigeri

- Secondary branches of peduncle more than 2 ............................................................................................................................... 19.

19. Berries pyriform or triangular when dry ....................................................................................................................................... 20.

- Berries globose, ovoid or ellipsoid when dry ................................................................................................................................ 21.

20. Terminal leaflets ovate–lanceolate, 3–4 × 6–9 cm; berries pyriform when dry ....................................................... 20. T. pyriforme

- Terminal leaflets obovate or elliptic, 4‒5.5 × 9‒12 cm; berries triangular when dry ..................................... 22. T. rumicispermum

21. Inflorescences compound umbel on pseudo-terminal branch or axile, umbelliform, loose; tendrils bifurcate ..... 23. T. serrulatum

- Inflorescences compound umbel on axile, globose, compact; tendrils unbranched ...................................................................... 22.

22. Female flower disc inconspicuous ..................................................................................................................... 16. T. pachyphyllum

- Female flower disc conspicuous, thick and adnate to lower part of ovary .................................................................................... 23.

23. Stigmas 4 pointed lobes, glabrous .................................................................................................................................. 9. T. dubium

- Stigmas more or less rounded, papillose ................................................................................................................. 12. T. harmandii

24. Leaflets broadly elliptic or ovate ................................................................................................................................................... 25.

- Leaflets narrowly elliptic or lanceolate .......................................................................................................................... 9. T. dubium

25. Leaflets pubescent along nerve or at least along the midrib on the lower surface ........................................................................ 26.

- Leaflets pubescent on both surfaces .............................................................................................................. 14. T. macrocorymbum

26. Berries up to 1.5 cm in diam ....................................................................................................................................... 18. T. pilosum

- Berries more than 2 cm in diam ................................................................................................................................ 24. T. siamense

27. Berries 2‒2.5 cm in diam .......................................................................................................................................... 25. T. teaniatum

- Berries 0.8‒1.5 cm in diam ............................................................................................................................................................ 28.

28. Outer petals densely papillose ......................................................................................................................... 13. T. leucostaphylum

- Outer petals glabrous ..................................................................................................................................................................... 29.

29. Secondary vein almost 90° with midrib; old branches verrucose, light brown; stigma 4 pointed lobes ...................... 8. T. delavayi

- Secondary vein angle nearly 45° with midrib; old branches flaky, grey; stigma 4 rounded lobes or nearly globose, not lobed ........ ............................................................................................................................................................................ 11. T. godefroyanum