Description

Shrub to 2m. Twigs 1–2mm in diameter, green, with stalked scales, conspicuously rough with the persistent protruding scale bases; internodes 1–4cm. Leaves 4–7 together in tight pseudowhorls. Blade 12–40 x 5–25mm, broadly elliptic to obovate; apex emarginate or rounded, with a small protruding mucronate gland; margin entire, slightly revolute; base narrowly tapering; upper surface green, glabrescent, lower surface sparsely covered with scales, pale green. Scales sub-circular, brown or translucent, mostly pale, variable in size and slightly impressed. Mid-vein impressed above and raised beneath, lateral veins 2–4 per side, weakly impressed above and raised beneath or obscure in smaller leaves. Petiole 2–4mm, grooved above, rounded below, brown scaly and very shortly hairy above. Flower buds 6–8 x 3–4mm, green becoming pale brown, ovate, smooth with broadly acute points. Bracts minutely shortly hairy outside and fringed with longer white hairs, glabrous inside. Bracteoles 1.5mm, filiform with a few white hairs, withering quickly. Pedicels 15–25 x c.1mm, green, moderately to densely scaly from an uneven surface. Inflorescence of solitary, or paired, flowers, semi-erect, horizontal to half-hanging. Flowers 6–8 x 16–22mm, campanulate. Calyx green, densely scaly, wavy to distinctly lobed with rounded or weakly triangular lobes to 3mm. Corolla yellow; tube 4–5 x 4–5 x 4–5mm, moderately densely scaly outside with inconspicuous translucent scales, and with long patent white hairs just below the mouth inside; lobes 6–8 x 5–7mm, the three upper patterned with rows of faint orange-brown spots on the inner side and with a few translucent scales outside, reflexed to the horizontal or a little beyond, overlapping up to 1⁄3. Stamens arranged all round the mouth but with a gap on the lower side where the style is placed, irregularly dimorphic and exserted to 5mm; filaments yellow, tapering to the base in the lower 1⁄3 and also upwards for about 2⁄3, with long patent white hairs in the middle part; anthers 2–2.5 x c.1mm, brown. Disc green, glabrous. Ovary 2.8 x 2.2mm, green, densely covered in silvery scales. Fruit 12–16 x 4–5mm, the pedicel turning to place them erect, green passing to brown, cylindrical with longitudinal grooves and a persistent deflexed style; valves splitting to the base and curving backwards, straight, not twisting, the placentae remaining firmly adherent to the central column. Seeds 4–4.7mm, bright orange-brown, without tails 1.2–1.9mm, the longest tail 1.2–1.5mm, tails mostly straight, sometimes a little crimped usually at just one end. ** * Rhododendron emarginatum * var. * eriocarpum * ** Differing chiefly in that the ovary is both hairy and scaly. The calyx lobes are also well developed, 1.8 x 2mm, with scales along the margins of the lobes. Seeds 2.5–3mm, without tails c.1mm, the longest tail 1.2mm.

Distribution

China, SE Yunnan, Pingbian, Xichou, Malipo and Mengzi. Guangxi, Daimiaoshan Xian, Pingshixiang, Jiuwandai shan. Vietnam, Province Lao Cai. ** * Rhododendron emarginatum * var. * eriocarpum * ** Known from the type locality in China and Guangxi Province, Daimiaoshan Xian, Pingshixiang, Jiuwandai shan

Altitude

Habitat

In tropical monsoon forests, often epiphytic on branches of trees

Nomenclatural History

R. euonymifolium H.Lév., Fedde Rep. 1913. 12: 228. R. poilanei Dop, Fl. Gén. I.-C. 1930. 3: 739. R. maguanense K.M.Feng, Acta Bot. Yunnan. 1983. 5(3): 268. R. leiboense Z.J.Zhao, Bull. Bot. Research 1987. 7(3): 57, f.1, 63.

Notes

References

Argent, G. (2006) Rhododendrons of subgenus Vireya. RHS:London. Page:31