Materials and Methods
Taxonomic Treatment
Key to the genera of Celastraceae in Vietnam
Stamens numerous ············································································································································· 1. Plagiopteron
Stamens 2–5.
2. Disk intrastaminal or stamens on disk; flowers unisexual or bisexual; fruit drupaceous, baccate, samaroid, or capsular; seeds with or without surrounding wings, arillate or exarillate.
3. Plants unarmed.
4. Leaves alternate on mature stems.
5. Leaves with reticulate secondary venation, petiole not geniculate.
6. Ovary with terminal style; stamens not alternating with staminodes; fruit dehiscent or indehiscent, not drupe with numerous stones.
7. Fruit capsular; ovules 1–12 per locule.
8. Scandent shrubs; inflorescence terminal or axillary, thyrsoid, cymose, or flowers solitary; flowers unisexual, rarely bisexual, dioecious; ovules 1–2 per locule; arils nearly enveloping seeds ··········· ············································································································································· 2. Celastrus
8. Erect or scandent trees or shrubs; inflorescence axillary, rarely terminal, cymose, fasciculate, or flowers solitary; flowers bisexual, rarely unisexual; monoecious or dioecious; ovules 1–12 per locule; arils basal to enveloping seeds ························································································ 3. Maytenus
7. Fruit samaroid; ovules 1–2 per locule ··············································································· 4. Tripterygium
6. Ovary with apical hollow and style-like central column arising from base of hollow; stamens alternating with small staminodes; drupe with numerous stones ······························································ 5. Siphonodon
5. Leaves with distinct crossbar secondary venation, petiole distally geniculate ····································· 6. Bhesa
4. Leaves decussate or opposite.
9. Petals slightly united at the base. Disk proper absent, filaments united at the base in a ring or short tube, by some interpreted to represent a disk, usually united with the petals ·········································· 7. Microtropis
9. Petals free. Disk conspicuous, fleshy, cupular or flat, free from the petals.
10. Ovary 3-, or 4–5 celled. Ovules 1–18 in each cell.
10. Ovary 2-celled, or 1-celled by abortion. Ovules 2 in each cell.
13. Disk more or less flat. Anthers subglobose and rounded at the apex, connective invisible on the dorsal side ·········································································································································· 11. Cassine
13. Disk cupular. Anthers ovoid and short-apiculate, connective distinct and broad on the dorsal side ············································································································································· 12. Pleurostylia
3. Plants with thorns or stems terminating in sharp points ·································································· 13. Gymnosporia
2. Disk extrastaminal; flowers bisexual; fruit baccate with seeds surrounded by mucilaginous arils, transversely-flattened, trilobed capsules with seeds with membranous basal wings or narrow stipes, or capsules that are circular or trigonous in cross section with seeds with membranous apical wings or arils basal to partially enveloping seeds.
14. Fruit baccate with seeds surrounded by mucilaginous arils ······································································ 14. Salacia
14. Fruit transversely-flattened, trilobed capsules with seeds with membranous basal wings or narrow stipes, or capsules that are circular or trigonous in cross section.
15. Ovules 2 per locule ·························································································································· 15. Reissantia
15. Ovules 3–22 per locule ················································································································ 16. Loeseneriella