Melaleuca leucadendra

Craven, L. A. & Cowie, I. D., 2013, Taxonomic notes on the broad-leaved paperbarks (Myrtaceae, Melaleuca), including the description of one new species from northern Australia and a key to all taxa, Blumea 57 (3), pp. 207-209 : 208-209

KEY TO THE MELALEUCA LEUCADENDRA SPECIES GROUP (based on Craven 1999)

1. Staminal filaments hairy......... M. lasiandra F.Muell.

1. Staminal filaments glabrous...................... 2

2. Hypanthium distinctly hairy (at least in bud).......... 3

2. Hypanthium glabrous or effectively so............. 18

3. Leaf blade indumentum with at least some of the hairs lanuginulose or sericeous-lanuginulose (whether or not also with pubescent to sericeous or sericeous-pubescent hairs) ............................................. 4

3. Leaf blade indumentum without lanuginulose or sericeous-lanuginulose hairs (the hairs sericeous, sericeous-pubescent or pubescent)................................. 9

4. Calyx lobes very broadly triangular (0.7 mm long).......................... M. ferruginea Craven & Cowie

4. Calyx lobes broadly ovate, ovate, subcircular or triangular............................................ 5

5. Stamens 5 – 8 mm long......................... 6

5. Stamens 10– 25 mm long....................... 7

6. Calyx lobes 0.5 – 0.8 mm long; triads clustered (less than 1 hypanthium diameter apart)..... M. saligna Schauer

6. Calyx lobes 0.9 –1.5 mm long; triads scattered (more than 1 hypanthium diameter apart) or sometimes partly clustered........................... M. dealbata S.T.Blake

7. Calyx lobes 1.9 – 2.5 mm long; petals 5.1–7 mm long.............................. M. triumphalis Craven

7. Calyx lobes 0.5 –1.5 mm long; petals 1.5– 3.5 mm long 8

8. Leaf oil glands more or less in rows; leaves 5 –20 times as long as wide, the blade 5–19 mm wide; hypanthium 1.3– 2 mm long; stamens 3 – 9 per bundle.. M. fluviatilis Barlow

8. Leaf oil glands scattered; leaves 1.6 –10.2 times as long as wide, the blade 5 – 40 mm wide; hypanthium 1.8– 3.5 mm long; stamens 3 –7 per bundle.......................................... M. nervosa (Lindl.) Cheel

9. Inflorescence up to 30 mm wide................. 10

9. Inflorescence more than 30 mm wide............. 17

10. Inflorescence up to 20 mm wide................. 11

10. Inflorescence more than 20 mm wide............. 13

11. Triads scattered (at least 1 hypanthium diameter apart, sometimes within an inflorescence some of the triads are closer).................. M. stenostachya S.T.Blake

11. Triads clustered (less than 1 hypanthium diameter apart)........................................... 12

12. Leaf blade apex acuminate, narrowly acute or acute................................. M. sericea Byrnes

12. Leaf blade apex usually obtuse, sometimes acute, rounded, obtusely shortly acuminate or retuse........................................... M. arcana S.T.Blake

13. Calyx lobes herbaceous in the proximal-central zone and scarious in a narrow marginal band; leaves 4.8 –14 times as long as wide............... M. argentea W.Fitzg.

13. Calyx lobes herbaceous in the proximal-central zone and scarious in a broad marginal band; leaves 1.3 – 9.7 times as long as wide.............................. 14

14. Older leaves with the secondary venation distinct and about as prominent as the major veins................. 15

14. Older leaves with the secondary venation more or less obscure........... M. quinquenervia (Cav.) S.T.Blake

15. Leaves (17–)25 –50(– 60) mm wide (leaves 1.3– 6.5 times as long as wide; stamens (8–)9 –12(–15) per bundle............. M. cajuputi Powell subsp. platyphylla Barlow

15. Leaves (6–)10– 28(– 39) mm wide............... 16

16. Leaves (6–)10 –16(– 26) mm wide, 2.8– 9.7 times as long as wide; stamens (6–)8 –11(–14) per bundle........................... M. cajuputi Powell subsp. cajuputi

16. Leaves (15–)19– 28(– 39) mm wide, 2.2– 2.9 times as long as wide; stamens (4 –)6 – 8(–10) per bundle)........... M. cajuputi Powell subsp. cumingiana (Turcz.) Barlow

17. Young shoots with the hairs completely appressed; hypanthium (1.8 –) 3 – 3.5 mm long; petals (2.7–) 4 –5.3 mm long; inflorescence axis sericeous or pubescent (occasionally glabrous)............... M. viridiflora Sol. ex Gaertn.

17. Young shoots with at least some spreading-ascending to spreading hairs; hypanthium 1.5 –2.5 mm long; petals 2.5 –3.5 mm long; inflorescence axis pubescent........................ M. quinquenervia (Cav.) S.T.Blake

18. Calyx lobes puberulous on the abaxial surface.................................... M. dealbata S.T.Blake

18. Calyx lobes glabrous on the abaxial surface........ 19

19. Calyx lobes herbaceous in the proximal-central zone and scarious in a narrow marginal band or the lobes herbaceous almost throughout............................ 20

19. Calyx lobes herbaceous in the proximal-central zone and scarious in a broad marginal band............... 21

20. Stamens 6 –7 mm long; leaves 30–110 mm long, 3.3 –9 times as long as wide; bark hard... M. clarksonii Barlow

20. Stamens 7–16 mm long; leaves 75– 270 mm long, 3.5–16.1 times as long as wide; bark papery M. leucadendra (L.) L.

21. Leaf blade narrowly ovate, very narrowly ovate, rarely narrowly elliptic or very narrowly elliptic (often falcate to subfalcate); leaves 3.5 –16 times as long as wide; petals with elliptic oil glands (occasionally long elliptic glands form an apparently linear gland)........ M. leucadendra (L.) L.

21. Leaf blade elliptic to very narrowly elliptic, obovate to very narrowly obovate (rarely broadly elliptic or ovate or very narrowly ovate or approaching falcate); leaves usually 1.3– 8.5 times as long as wide (in some forms of M. viridiflora 4.8 –15.7 times as long as wide with the blade very narrowly elliptic or narrowly elliptic or narrowly to very narrowly obovate); petals with linear, elliptic, circular to subcircular, or oblong oil glands................. 22

22. Stamens 9.2–10 mm long, the bundle claw 0.2 –0.4 times as long as the stamens.................................... M. cajuputi Powell subsp. platyphylla Barlow

22. Stamens (9.5 –) 10.5 –23 mm long, the bundle claw 0.06– 0.2(– 0.5) times as long as the stamens........... 23

23. Hypanthium (1.8–) 3– 3.5 mm long; petals (2.7–) 4 –5.3 mm long; inflorescence axis sericeous or pubescent (occasionally glabrous)............ M. viridiflora Sol. ex Gaertn.

23 Hypanthium 1.5– 2.5 mm long; petals 2.5 – 3.5 mm long; inflorescence axis pubescent...................................... M. quinquenervia (Cav.) S.T. Blake