厚叶杜鹃 hou ye du juan

Rhododendron ziyuanense P. C. Tam var. pachyphyllum (W. P. Fang) G. Z. Li.

Small trees, ca. 8 m tall; older branches grayish, glabrous; young shoots pale purple, scattered floccose. Petiole 10–15 mm, sparsely floccose; leaf blade thick, leathery, oblong to oblong-elliptic, rarely oblong-obovate, 5.5–6.5(–8.5) × 1.6–2.5 (–3.2) cm; base rounded or cuneate; apex acute, apiculate; abaxial surface floccose near base, glabrescent; adaxial surface green, glabrous; midrib prominent abaxially, grooved adaxially; lateral veins obscure on both surfaces. Inflorescence 4- or 5-flowered; rachis ca. 5 mm, glabrous. Pedicel 1.5–2.5 cm, glabrous; calyx cupular; lobes 5, ca. 1 mm; corolla campanulate, creamy-white, with purple flecks, ca. 3 cm, lobes 5, obovate, ca. 1.5 cm, emarginate; stamens 10, unequal, 1–2 cm, filaments pubescent at base; ovary ovoid, ca. 5 mm, purple, glandular; style ca. 2 cm, glabrous; stigma swollen, disk-shaped, ca. 2.6 mm in diam. Capsule ca. 20 × 5 mm, calyx and style persistent. Fl. May.

Forests; 1800–1900 m. NE Guangxi, SW Hunan.