林生杜鹃 lin sheng du juan

Rhododendron lanigerum var. silvaticum (Cowan) Davidian; R. silvaticum Cowan.

Shrubs or trees, 2.7–6 m tall; branches stout, usually crooked and gnarled, ca. 5 mm in diam. below inflorescence, thinly grayish tomentose. Petiole rounded abaxially, grooved adaxially, 15–25 mm, glabrous above, densely gray-tomentose; leaf blade leathery, oblong-lanceolate or oblong-oblanceolate, 11.5–14.5(–22) × 2–3.3(–7) cm; base obtuse to cuneate; margin revolute; apex acuminate, cuspidate; abaxial surface with indumentum 2-layered, dense, whitish to fawn, upper layer densely woolly-tomentose, hairs dendroid, lower layer thin, compacted; adaxial surface rugulose, glabrous at maturity though often with traces of indumentum along midrib; midrib deeply grooved; primary veins 12–15-paired, impressed. Inflorescence a congested racemose truss, 20–30-flowered; rachis stout, ca. 20 mm, with dense fawn or ferruginous tomentum. Pedicel 1–1.2 cm, pubescent; calyx fleshy; lobes 5, ca. 2 mm, triangular, glabrous; corolla campanulate, fleshy, deep pink to rosy purple, ca. 3.5 cm, with 5 darker basal nectar pouches; lobes 5, suborbicular, ca. 1.5 × 2 cm, apex emarginate; stamens 10, unequal, 1.4–1.9 cm, filaments white, glabrous; ovary cylindric-conoid, ca. 8 × 2.2 mm, densely fawn or grayish tomentose; style ca. 1.9 cm, glabrous, stigma small. Capsule shortly oblong, ca. 20 × 7 mm. Fl. Apr, fr. not known.

Forests; 2700–3100 m. SE Xizang [NE India].