540. Rhododendron viscidum C. Z. Guo & Z. H. Liu, Acta Bot. Yunnan. 10: 497. 1988.
粘质杜鹃 nian zhi du juan
Small shrubs, to 1 m tall; young shoots slender, densely coarsely red-brown-strigose, hairs flat. Petiole 2–6 mm, coarsely strigose; leaf blade leathery, obovate to elliptic-obovate or elliptic, 1–2 × 0.5–1.2 cm; base narrowly cuneate; margin slightly revolute, ciliate; apex acute and mucronate; both surfaces coarsely red-brown-strigose; lateral veins 3–4-paired, not reaching margin. Inflorescence 4- or 5(–9)-flowered; flower buds very sticky. Pedicel 0.5–0.7 cm, coarsely red-brown-strigose, hairs flat; calyx lobes triangular-lanceolate, 2–3 mm, margin long-ciliate; corolla funnelform, pinkish purple or pale white, with dark red flecks on upper 3 lobes, 1–1.3 cm; tube cylindric, ca. 6 mm, outer surface villous and shortly glandular, inner surface pubescent; lobes ovate, 0.6–0.7 cm, outer surface puberulent along midrib; apex obtusely pointed; stamens 5, unequal, exserted; filaments pubescent at base; style shorter than stamens, puberulent at base. Capsule ovoid, 6–7 mm, red-brown-strigose. Fl. Apr–May, fr. Oct–Nov.
Forests; 1800–2000 m. S Hunan.
From the original description, Rhododendron viscidum appears closely allied to, and is probably synonymous with, R. viscigemmatum. The two species were described from adjacent parts of Hunan and Guangxi, respectively.