Bruguiera species

Duke, N. C. & Kudo, H., 2018, Bruguiera × dungarra, a new hybrid between mangrove species B. exaristata and B. gymnorhiza (Rhizophoraceae) recently discovered in north-east Australia, Blumea 63 (3), pp. 279-285 : 283

Key to Bruguiera species and hybrids (see Table 3)

1. Inflorescence consisting of a single flower (flowers solitary)......................................... 2

1. Inflorescence 1–5-flowered, rarely 1................ 6

2. Petals without a central spine, or spine minute, c. 0.2 mm long................................ B. exaristata

2. Petals with a central spine, greater than 2 mm long.... 3

3. Petals without apical bristles or bristles minute, c. 0.3 mm long............................... B. sexangula

3. Petals with apical bristles,> 1 mm long.............. 4

4. Petal lobes with 3 or 4 bristles; bristles> 2 mm long...................................... B. gymnorhiza

4. Petal lobes with commonly 2 bristles; bristles <2 mm long ............................................. 5

5. Calyx tube of mature flower bud ribbed; <10 lobes, edges of adjoining lobes antrorse or raised to form ridges at lobe junctions........................... B. × dungarra

5. Calyx tube of mature flower bud mostly smooth; ≥ 10 lobes, lobe margins flat or retrorse to form grooves at lobe junctions.......................... B. × rhynchopetala

6. Mature flower buds 18–22 mm long, calyx lobes 9–11....................................... B. × hainesii

6. Mature flower buds 10–15 mm long, calyx lobes 8 or 9. 7

7. Calyx lobes stout, 2–3 mm long; fruit calyx lobes adpressed against hypocotyl...................... B. parviflora

7. Calyx lobes elongate, 4–6 mm long; fruit calyx lobes reflexed at right angles to the hypocotyl........... B. cylindrica