蜡叶杜鹃 la ye du juan

Rhododendron admirabile I. B. Balfour & Forrest; R. adroserum I. B. Balfour & Forrest; R. ceraceum I. B. Balfour & W. W. Smith; R. gymnanthum Diels; R. lukiangense subsp. admirabile (I. B. Balfour & Forrest) Tagg; R. lukiangense subsp. adroserum (I. B. Balfour & Forrest) Tagg; R. lukiangense subsp. ceraceum (I. B. Balfour & W. W. Smith) Tagg; R. lukiangense subsp. gymnanthum (Diels) Tagg.

Shrubs or small trees, 2–4 m tall; older branches gray, bark exfoliating; young shoots stout, glabrous. Petiole cylindric, 10–20 mm, glabrous; leaf blade leathery, elliptic to oblanceolate, 8–14 × 2.5–4.5 cm; base cuneate; margin entire or slightly undulate; apex acuminate; both surfaces glabrous; abaxial surface pale green, glabrous; adaxial surface dark green, with thin wax-coating at maturity, somewhat shiny, glabrous; midrib prominent abaxially, grooved adaxially; lateral veins 22–24-paired, distinct abaxially, obscure adaxially. Inflorescence racemose-umbellate, 7–13-flowered; rachis 15–30 mm, pubescent. Pedicel 1–1.5 cm, usually glabrous; calyx lobes 5, 1–2 mm, ovate-triangular, glabrous; corolla tubular-campanulate, pale to deep magenta rose, with purple flecks and basal blotch, 3–4.5 cm, lobes 5, suborbicular, ca. 1.5 × 2 cm, emarginate; stamens 10, 1.5–3 cm unequal, filaments glabrous; ovary narrowly cylindric, 5–7 × ca. 2 mm, glabrous; style 3.5–4 cm, glabrous, stigma small. Capsule narrowly cylindric, ca. 30 × 5 mm, glabrous and smooth; calyx persistent, ca. 3 mm at maturity. Fl. Apr–May.

Pinus forests, mixed woodlands, thickets, valleys, stream banks; 2600–3500 m. SW Sichuan, SE Xizang, NW Yunnan.