Rhododendron arizelum I. B. Balf. & Forrest

Rhododendron arizelum var. rubicosum Cowan & Davidian (Rhododendron Year book 8: 79. 1953), described from NW Yunnan, is a rich red- to purple-flowered form, which may be intermediate between R. arizelum and R. rex subsp. fictolacteum.

Shrubs or small trees, 3–7 m tall; branchlets stout, rough, usually ca. 10 mm in diam.; young shoots pale brown tomentose, glabrescent. Petiole terete, 20–30 mm, tomentose, glabrescent; leaf blade leathery, obovate or obovate-elliptic, broadest above middle of blade, 9–19 × 4–8 cm; base cuneate; apex rounded, emarginate; abaxial surface with pale brown or rufous, 2-layered indumentum, upper layer brown, hairs narrowly cup-shaped, strongly fimbriate, lower layer thin, compacted, gray; adaxial surface deep green, glabrous, midrib prominent abaxially, flat or slightly impressed adaxially, lateral veins 10–13-paired, prominent abaxially. Inflorescence 15–20-flowered; rachis 15–25 mm, densely tomentose. Pedicel 1.2–2 cm, densely tomentose; calyx oblique; teeth 8, ca. 1 mm; corolla campanulate, white, pale yellow or pink, with crimson basal blotch, 3.5–4.5 cm, lobes 8, suborbicular, ca. 1 × 1.5 cm, emarginate; stamens 16, 1.5–2.5 cm, filaments glabrous or puberulent at base; ovary terete, densely tomentose; style glabrous. Capsule 30–40 × ca. 10 mm, tomentose. Fl. May–Jun, fr. Aug–Sep.

SE Xizang, W Yunnan [NE Myanmar].

Pinus forests, Rhododendron thickets; 2500–4000 m.

Rhododendron arizelum (夺目杜鹃) is a species of flowering plant in the family Ericaceae. It is native to northeastern Myanmar, southeastern Tibet, and western Yunnan, China, where it grows at altitudes of 2,500–4,000 m (8,200–13,100 ft). It is a shrub or small tree that typically grows to 3–7 m (9.8–23.0 ft) in height, with leathery leaves that are obovate or obovate-elliptic, and 9–19 × 4–8 cm in size. The flowers are white, pale yellow, or pink, with a crimson basal blotch.