Rhododendron bonvalotii Bur. & Franch.

This species has the flower characters of Rhododendron subsect. Thomsonia, but the elliptic or oblong-oblanceolate leaves resemble those of R. selense, suggesting that it could be hybrid of R. selense, possibly with R. souliei. It has not been seen since it was first collected over a century ago.

Shrubs; young shoots glabrous. Petiole cylindric, 5–8 mm, shortly glandular-hairy; leaf blade elliptic or oblong-lanceolate, 4–5 × ca. 1.5 cm; base obtuse or rounded; margin revolute; apex acute; abaxial surface greenish, glabrous; adaxial surface deep green, slightly shiny, with 2–4 longitudinal ridges towards the apex; midrib prominently raised abaxially, grooved adaxially; lateral veins 12–14-paired, obscure. Inflorescence racemose-umbellate, usually 4- or 5-flowered; rachis stout, ca. 15 mm, shortly glandular-hairy. Calyx lobes 5, ca. 4 mm, ovate or irregularly suborbicular, fringed with glands; corolla campanulate, pale pink, 2–2.5 cm, lobes 5, suborbicular, ca. 1 × 1.5 cm, emarginate; stamens 10, 1–1.5 cm, unequal, filaments glabrous; ovary ovoid, 4–6 mm, densely glandular; style glandular to tip. Capsule not known.

W Sichuan (near Kangding).