All Floras      Advanced Search
FOC Vol. 14 Page 263 Login | eFloras Home | Help
FOC | Family List | FOC Vol. 14 | Ericaceae

2. Rhododendron subsect. Maddenia (Hutchinson) Sleumer, Bot. Jahrb. Syst. 74: 533. 1949.

有鳞大花亚组 you lin da hua ya zu

Fang Ruizheng (方瑞征 Fang Rhui-cheng); David F. Chamberlain

Rhododendron ser. Maddenia Hutchinson in J. B. Stevenson, Sp. Rhodod. 447. 1930 ["Maddenii"].

Shrubs or small trees, 0.3–4(–8) m tall; epiphytic or terrestrial; young shoots with scales often brown, otherwise glabrous, hispid or villous. Leaf blade leathery; adaxial surface scales dense, unequal, otherwise often glabrous except for midrib; adaxial surface often glabrous, sometimes scaly and/or hairy. Inflorescence terminal, a broad and large umbel or short raceme, 1–5(–11)-flowered. Calyx developed or not, 1–30 mm, 5-lobed, ciliate or not; corolla tubular-campanulate to funnelform, white or yellow, sometimes tinged pink, rarely pale purple or red, outer surface usually scaly, hairy in tube; stamens (9–)10 (15–25 in R. maddenii); ovary 5- or 6-locular (10–12-locular in R. maddenii); style rarely shorter than stamens, slightly curved, lower part scaly, rarely glabrous. Capsule often large, ovoid to cylindric, 5–50(–70) mm, densely scaly. Seed winged, with flipperlike structure.

About 45 species: Bhutan, China, India, Laos, Myanmar, Nepal, Sikkim, Thailand, Vietnam; 34 species (18 endemic) in China.

1 Stamens 15–25(–27); ovary 10–12-locular; petioles adaxially grooved.   4 Rhododendron maddenii
+ Stamens (8–)10(–14); ovary 5–7-locular.   (2)
2 (1) Calyx margin not or only rarely hairy, lobes large, 0.8–3 cm; petiole rounded adaxially (concave in R. megacalyx, then with pedicels and calyx whitish pruinose).   (3)
+ Calyx margin hairy, rarely glabrous, small or with obvious lobes; petiole grooved adaxially.   (13)
3 (2) Pedicels and calyx not scaly, whitish pruinose; calyx lobed to the middle, lobes 2–3 cm; capsule shorter than persistent calyx; midrib and petiole concave adaxially.   5 Rhododendron megacalyx
+ Pedicels and calyx scaly; calyx lobed to the base; capsule longer than persistent calyx; midrib and petiole raised or flat adaxially.   (4)
4 (3) Leaf blade 11–26 × (3.5–)6–12 cm; corolla 9–13.5 cm.   (5)
+ Leaf blade less than 16 × 6 cm; corolla 3.5–10 cm.   (7)
5 (4) Leaf blade with veins flat on adaxial surface.   8 Rhododendron excellens
+ Leaf blade with veins strongly impressed on adaxial surface.   (6)
6 (5) Pedicels and calyx glabrous; capsule 3–3.5 cm; abaxial leaf surface with dense small scales and scattered large scales.   6 Rhododendron nuttallii
+ Pedicels and calyx densely pubescent; capsule 5–7 cm; abaxial leaf surface with more large scales.   7 Rhododendron sinonuttallii
7 (4) Young shoots sparsely hispid; pedicels and calyx pubescent.   9 Rhododendron dalhousieae
+ Young shoots, pedicels and calyx with scales only.   (8)
8 (7) Leaf blade 2–5 × (0.5–)1.5–2.5 cm; corolla 3.5–6 cm; petiole 3–5 mm (not recorded for R. mianningense).   (9)
+ Leaf blade 6–16 × (1.5–)2–6 cm; corolla 6–9(–10) cm; petiole 10–30 mm.   (10)
9 (8) Calyx 15–18 mm; corolla ca. 3.5 cm, pale yellow, outer surface not scaly; abaxial leaf surface with scales overlapping or only slightly apart; petiole glabrous.   10 Rhododendron mianningense
+ Calyx 7–8 mm; corolla 4–6.2 cm, white, outer surface scaly; abaxial leaf surface with scales 1–2 × their diameter apart; petiole hispid.   11 Rhododendron kiangsiense
10 (8) Stamens 5; corolla lobes denticulate; calyx not scaly outside.   13 Rhododendron chunienii
+ Stamens 10; corolla lobes entire; calyx scaly outside.   (11)
11 (10) Calyx lobes 15–20 mm, leaflike; pedicel ca. 20 mm; abaxial leaf surface with scales uniform in size.   12 Rhododendron taggianum
+ Calyx lobes 1–10(–14) mm; pedicel 10–15 mm; abaxial leaf surface with scales unequal in size.   (12)
12 (11) Calyx 1–5 mm; adaxial leaf surface with scales.   14 Rhododendron lindleyi
+ Calyx 8–10(–14) mm; adaxial leaf surface without scales.   15 Rhododendron liliiflorum
13 (2) Calyx lobes 6–12 mm; young shoots hispid, rarely glabrous; petiole, and usually also leaf blade, hairy.   (14)
+ Calyx lobes obsolete or with lobes 2–6 mm; young shoots, leaf blade or petiole hispid or glabrous.   (21)
14 (13) Leaf blade without hairs on both surfaces, sometimes hairy on margin; petioles glabrous or hispid; styles glabrous or with a few scales at base.   (15)
+ Leaf blade hispid or villous, at least along central vein; petioles hispid or villous; styles glabrous to densely scaly.   (17)
15 (14) Leaf margin glabrous; abaxial surface with scales contiguous; corolla scaly outside; calyx margin glabrous.   18 Rhododendron changii
+ Leaf margin hairy, abaxial surface with scales sparse, 3–6 × their diameter apart; corolla not scaly outside; calyx margin densely hairy.   (12)
16 Leaf margin hispid, slightly dentate; calyx lobes ovate-lanceolate; corolla yellow.   16 Rhododendron fletcherianum
+ Leaf margin villous, hairs caducous, entire; calyx lobes oblong; corolla white, or tinged pale red.   17 Rhododendron yungchangense
17 (14) Young shoots, leaves and pedicels rusty brown-villous; leaf margin glabrous; calyx lobes linear, 6–12 × ca. 2 mm wide.   19 Rhododendron linearilobum
+ Young shoots, leaves and pedicels hispid, or petioles glabrous; leaf margin often densely hispid; calyx lobes ovate, broadly ovate, or oblong-ovate.   (18)
18 (17) Corolla white or tinged with pale red, not scaly outside.   (19)
+ Corolla pale or fresh yellow, scaly outside.   (20)
19 (18) Leaf apex obtuse to rounded, sometimes emarginate, pubescent below; scales on abaxial leaf surface slightly more than their own diameter apart (see also 21. R. yizhangense and 22. R. yaogangxianense).   20 Rhododendron levinei
+ Leaf apex acute to acuminate, hispid along central vein below; scales on abaxial leaf surface 2–3 × their diameter apart.   23 Rhododendron ciliatum
20 (18) Young shoots not hispid; pedicels glabrous; corolla pale yellow, glabrous; leaf margin flat or slightly revolute, villous or glabrous near the base.   24 Rhododendron amandum
+ Young shoots densely brownish hispid; pedicels sometimes strap-shaped-setose; corolla fresh yellow, densely pubescent; leaf margin revolute, densely strap-shaped-setose.   25 Rhododendron valentinianum
21 (13) Inflorescence 1(–2)-flowered.   (22)
+ Inflorescence 2–5-flowered.   (23)
22 (21) Young shoots densely brownish scaly; leaf margin densely villous, abaxial surface pale green, scales 1–2 × their own diameter apart.   26 Rhododendron ciliipes
+ Young shoots and leaf margin sparsely hispid, abaxial surface dark brown, scales less than 1 × their own diameter apart.   27 Rhododendron pseudociliipes
23 (21) Abaxial leaf surface densely scaly; scales unequal, generally less than (rarely 1 ×) their own diameter apart.   (24)
+ Abaxial surface of leaves sparsely scaly; scales unequal, (0.5–)1.5–5 × their own diameter apart.   (28)
24 (23) Abaxial leaf surface brown when dry; blade rhombic-elliptic or rhombic-lanceolate   28 Rhododendron rhombifolium
+ Abaxial leaf surface grayish green or grayish white when dry; blade elliptic or oblong-elliptic, ovate, obovate or elliptic-lanceolate.   (25)
25 (24) Corolla 3.5–4.3 cm, yellow, 5-lobed to the middle.   29 Rhododendron leptocladon
+ Corolla 5–7 cm, white tinged with pale red, 5-lobed to upper 1/3.   (26)
26 (25) Calyx obsolete, margin not ciliate; scales on abaxial leaf surface unequal, to 1 × their own diameter apart.   30 Rhododendron dendricola
+ Calyx undulate, 5-lobed, margin long ciliate hairs; scales on abaxial leaf surface of leaves ± uniform, less then their own diameter apart to almost contiguous.   (27)
27 (26) Leaf blade ovate, widest below the middle; pedicel 1–2 cm.   31 Rhododendron roseatum
+ Leaf blade elliptic, oblong-elliptic, elliptic-lanceolate or obovate, widest at or above the middle; pedicel 0.5–1 cm.   32 Rhododendron pachypodum
28 (23) Shoots and petioles densely hispid when young; corolla not scaly, only pubescent outside.   33 Rhododendron ciliicalyx
+ Shoots and petioles glabrous or sometimes sparsely hispid when young; corolla ± scaly outside, sometimes also pubescent.   (29)
29 (28) Leaf blade oblong-lanceolate or oblong-elliptic; apex acuminate or acute; style longer than corolla.   (30)
+ Leaf blade oblong-obovate, oblong-elliptic or obovate; apex rounded to acute or apiculate; style as long as corolla.   (31)
30 (29) Pedicel densely pubescent; calyx margin glabrous; corolla 4–5 cm, white, with or without yellow spots inside.   34 Rhododendron taronense
+ Pedicel glabrous; calyx margin sometimes long ciliate; corolla 6–7 cm, white or creamy yellow, with green spots inside.   35 Rhododendron walongense
31 (29) Leaf blade 3.4–4.5 cm, hispid; pedicel 0.6–0.8 cm; corolla glabrous outside; capsule ca. 0.9 cm.   36 Rhododendron wumingense
+ Leaf blade 4–12 cm, margin glabrous; pedicel 0.8–1.8 cm; corolla pubescent or shortly hairy outside; capsule 1.2–2 cm.   (32)
32 (31) Leaf blade 7–12 cm; abaxial surface densely or sparsely scaly, adaxial surface sparsely scaly; corolla ca. 7 cm; scales unequal.   30 Rhododendron dendricola
+ Leaf blade 4–8 cm; abaxial surface sparsely scaly, adaxial surface without scales; corolla 4–6 cm; scales nearly uniform in size.   37 Rhododendron scopulorum

  • List of lower taxa


  • Flora of China @
    Browse by
    Advanced Search

    Flora of China Home




     |  eFlora Home |  People Search  |  Help  |  ActKey  |  Hu Cards  |  Glossary  |