Syzygium, Gaertner, 1788

Lê, Th ị-Hương, Nguy ễn, Thành-Chung, Tr ần, Th ị-Thuý-Nga, Đ ỗ, Ng ọc-Đài & Lý, Ng ọc-Sâm, 2024, Syzygium ngheanense (Myrtaceae: Myrtoideae), a new species of Syzygium from Central Vietnam, Phytotaxa 641 (3), pp. 228-234 : 233

Key to the hairy species of Syzygium in Indochina

1. Twigs and leaves scabrid hairs; ovules ≤ 10 per locule; fruits sub-globose ......................................................................................2

- Twigs and leaves glabrous; ovules 16–18 per locule; fruits ovoid ........................................ S. levinei ( China, Cambodia, Vietnam)

2. Leaf blades glabrous; fruits somewhat rugose, glabrous....................................................................................................................3

- Leaf blades densely scabrid on both surfaces; fruits smooth, hairy near calyx ring.............................. S. scarbum ( Thailand, Laos)

3. Lateral nerves 16–27 pairs, glabrous; bracts, bracteoles and sepals glabrous; stamens 15–17 mm long; styles 17–18 mm long....... ..................................................................................................................................................................... S. ngheanense ( Vietnam)

- Lateral nerves 10–16 pairs, scabrid on abaxial surface of lamina; bracts, bracteoles and sepals scabrid; stamens c. 1.5 mm long; styles 4–5 mm long....................................................................................................................... S. vestitum ( China, Laos, Vietnam)