471. Rhododendron stamineum Franchet, Bull. Soc. Bot. France. 33: 236. 1886.
长蕊杜鹃 chang rui du juan
Shrubs or small trees, 3–7 m tall; young shoots thin, glabrous. Petioles 8–20 mm, glabrous or shortly glandular-setose; leaf blade elliptic or oblong-lanceolate, 6.5–13 × 2–5.5 cm; base cuneate to subrounded; margin slightly revolute; apex acuminate or obliquely acuminate; abaxial surface rarely white-powdery when dried, glabrous or shortly setose towards base; adaxial surface glabrescent, veins obsolete. Inflorescence subapical, (3–)5–8-flowered; flower buds conical, scales ovate, imbricate, pubescent only on the margin and at the apex. Pedicel 2–2.5 cm, glabrous or grayish tomentose when young; calyx lobes minute, triangular, glabrous; corolla funnelform tapering into narrow tube, white to occasionally pink, the upper lobes with yellow flecks within, 3–3.5 cm, tube ca. 13 mm wide; stamens 10, slender, long-exserted, filaments puberulent in lower part; ovary cylindric, tapering into style, ca. 4 mm, glabrous or densely gray-white-tomentose when young; style 4–5 cm, longer than stamens. Capsule cylindric, slightly curved, apex acuminate, 25–40 mm, glabrous. Fl. Apr–May, fr. Jul–Oct.
Mixed forests, open forests, forest margins, thickets, mountains; 400–1500 m. Anhui, Guangdong, Guangxi, Guizhou, Hubei, Hunan, Jiangxi, Shanxi, Sichuan, Yunnan, Zhejiang.