332. Rhododendron hypoglaucum Hemsley, J. Linn. Soc., Bot. 26: 25. 1889.
粉白杜鹃 fen bai du juan
Rhododendron argyrophyllum Franchet subsp. hypoglaucum (Hemsley) D. F. Chamberlain; R. gracilipes Franchet.
Shrubs, 3–10 m tall; bark gray; shoots smooth, greenish, glabrous. Petiole cylindric, 10–20 mm, glabrous; leaf blade leathery, lanceolate-elliptic or lanceolate-obovate, 6–10 × 2–3.5 cm; base cuneate; margin slightly revolute; apex acute or apiculate; abaxial surface indumentum thin, smooth, silvery-white; adaxial surface bright green, smooth, glabrous, midrib conspicuously prominent abaxially, grooved adaxially; lateral veins 10–14 on each side, blunt on both surfaces. Inflorescence 4–9-flowered; rachis 5–15 mm, with yellowish pubescence, glabrescent. Pedicel 2–3 cm, glabrous; calyx membranous; lobes 5, ca. 2 mm, ovate-triangular; corolla funnel-campanulate, narrowed at base, white flushed pink or pale rose, with numerous deep rose or purple spots, 2.5–3.5 cm, lobes 5, orbicular, ca. 1 × 1.5 cm, emarginate; stamens 10, unequal, 1.5–2 cm, filaments flattened towards the base, densely white-puberulent below; ovary cylindric, 4–5 mm, glabrous or rarely with glandular hairs at apex; style 2–2.5 cm, glabrous, Capsule cylindric, 6-valved at maturity, 20–25 × ca. 6 mm, glabrous. Fl. Apr–May, fr. Jul–Sep.
Thickets; 1500–2100 m. Chongqing, W Hubei, S Shaanxi, E Sichuan.