Description from Flora of China
Azalea ovata Lindley, J. Hort. Soc. London 1: 149. 1846; Rhododendron lamprophyllum Hayata; R. ovatum var. lamprophyllum (Hayata) Y. C. Liu; R. ovatum var. prismatum P. C. Tam; R. ovatum var. setuliferum M. Y. He.
Shrubs, 2–4(–6) m tall; young shoots sparsely glandular-hairy and pubescent. Petiole ca. 8 mm, narrowly winged, pubescent; leaf blade ovate to oblong-elliptic, 3.5–5 × 1.9–2.5 cm; base rounded or rarely broadly cuneate; margin slightly curved; apex acute and mucronate; adaxial surface glabrous or pubescent; lateral and net veins inconspicuous abaxially. Inflorescence subapical, 1-flowered. Pedicel 0.8–1.8 cm, densely gray-brown pubescent, also with short glandular hairs; calyx deeply lobed; lobes ovate or oblong-ovate, 4–5 × 3–4 mm, densely gray-brown pubescent, also sparsely glandular hairy at base abaxially, margin glabrous; corolla rotate, purplish, purple, or pink, with purple flecks inside tube, 1.6–2.3 cm, outer surface glabrous, inner surface puberulent; lobes oblong-obovate or broadly obovate; stamens 5, unequal, 1.5–2.1 cm, slightly shorter than corolla, filaments flat, pubescent in lower half; ovary ovoid, with dense short glandular hairs; style ca. 2.4 cm, exserted, glabrous. Capsule broadly ovoid, ca. 8 × 6 mm, densely gray-brown pubescent, also sparsely glandular. Fl. Apr–May, fr. Jul–Oct.
Gao Lianming (pers. comm.) notes that recent field studies have shown that the differences used to separate var. setuliferum from the type of the species, namely the narrower leaf blade and the style with dense bristles near the base, are not even borne out by the type of this variety, and in any case these features vary continuously between the two varieties.
Thickets; 300–1600 m. Anhui, Fujian, Guangdong, Guangxi, Guizhou, Hubei, Hunan, Jiangsu, Jiangxi, Sichuan, Taiwan, Zhejiang.