西昌杜鹃 xi chang du juan

Shrubs, 1–2 m tall. First-year shoots spreading, purple, densely scaly. Leaf blade leathery, ovate, 2.5–5 × 0.8–1.8 cm; base cuneate; apex acute; abaxial surface scales 0.5–1 × their own diameter apart, unequal, brown; adaxial surface deep green, sparsely scaly. Inflorescence terminal, umbellate, 2–5-flowered. Pedicel thin, purple, 1.8–2.5 cm, densely scaly; calyx rimlike, ca. 1.5 mm, scaly at base; corolla broadly funnelform-campanulate, white or pink, inside without spots, 1.5–1.8 cm; stamens 10, unequal, 2–2.5 cm, longer than corolla, filaments glabrous or pubescent below; ovary densely scaly; style 2.2–2.7 cm, longer than corolla, glabrous.

About 2200 m. Sichuan.

Geng et al. (Acta Phytotax. Sin. 41: 492. 2003) proposed that Rhododendron xichangense should be treated as a synonym of R. davidsonianum. The key character separating these two species is the spacing of the scales on the abaxial surfaces of the leaves. However, the description of R. davidsonianum suggests that that species is very variable in this character, encompassing the range of variation of R. xichangense.