Syzygium, Gaertner, 1788

Byng, James W., Barthelat, Fabien, Snow, Neil & Bernardini, Benedetta, 2016, Revision of Eugenia and Syzygium (Myrtaceae) from the Comoros archipelago, Phytotaxa 252 (3), pp. 163-184 : 175

Key to native and non-native species of Syzygium

1. Crushed leaves with smell of cloves; hypanthium clavate....................................................................................... 1. S. aromaticum

- Crushed leaves typically aromatic but not of cloves; hypanthium infundibuliform, obconical or pyriform.....................................2

2. Leaves less than 4.5 cm long..............................................................................................................................................................3

- Leaves equal or more than 4.5 cm long..............................................................................................................................................4

3. Leaves suborbicular, 1.2–2.5 cm long; apex cuspidate [Anjouan]...............................................................................8. S. tringiense

- Leaves elliptic or oblong, 2‒4.5 cm long; apex acute or acuminate [ Mayotte] ........................................................... 4. S. humblotii

4. Petals ≥ 1 cm long, free [cultivated or naturalised]............................................................................................................................5

- Petals <1 cm long, calyptrate [native, cultivated or naturalised]......................................................................................................6

5. Inflorescences ramiflorous, flowers in clusters, red to pink...................................................................................... 7. S. malaccense

- Inflorescences in terminal cymes, flowers white to yellow ............................................................................................. 5. S. jambos

6. Stamens 8‒13 mm long; flowers ca. 10‒20 mm in diameter at anthesis [ Mayotte] ......................................................... 6. S. labatii

- Stamens 3‒8 mm long, if 8 mm long then flowers ca. 5‒10 mm in diameter at anthesis..................................................................7

7. Hypanthium 2‒3 × 2‒2.5 mm; inflorescences lateral in axils of fallen leaves on older stems or (less often) terminal or axillary..3. S. cumini

- Hypanthium 3‒6 × 3‒6 mm; inflorescences terminal or in subterminal axils ........................................................... 2. S. comorense