In Hook., Ic. Pl. 1852. t.890.
Verified by:
Shrub or tree to 5m. Twigs c.3mm in diameter, initially laxly covered with scales and sometimes with very fine papillose hairs, later glabrescent but with thick raised leaf scars; internodes 1–4cm. Leaves 5–8 in dense pseudowhorls. Blade 10–35 x 6–25mm, broadly elliptic, ovate- or obovate-elliptic or sub-circular; apex obtuse, often rounded-obtuse, sometimes slightly emarginate, with an inconspicuous apical gland; margin slightly recurved, distinctly crenulate; base rounded, cordate, or broadly tapering, sub-densely to laxly scaly on both sides initially, early glabrescent with minute pits above; more persistently scaly beneath. Scales irregularly crenate or lobed with a narrow marginal zone; centre often large, swollen and persistent, deeply impressed. Mid-vein narrow and slightly impressed above, broad and obtusely prominent beneath; lateral veins 5–6 per side, somewhat irregular, spreading, slightly impressed above in old leaves, inconspicuous beneath, reticulation lax and faintly impressed above, obscure beneath. Petiole 1.5–3 x 1–3mm, grooved above, flattened, rugose. Flower buds (see p.327) to 17 x 11mm, ovoid, green, with the points of the bracts standing erect away from the bud. Outer bracts ovate-acuminate, the dorsal mid-vein tapering to a short subulate acumen, hairy and laxly scaly outside, hairy inside, margins ciliate near the apex only; inner ones ovate-obtuse to spathulate. Bracteoles to 20 x 1mm, linear below, sub-spathulate distally. Inflorescence of 5–10 flowers in open umbels. Flowers semi-erect to half-hanging. Pedicels 12–24 x 1–2mm, sub-stellately scaly. Calyx 3–4mm in diameter, a low scaly disc, often revolute. Corolla 26 x 37mm, broadly funnel-shaped or sub-campanulate, pink to deep red, strongly honey-scented; tube 15–18 x 4–5 x 12–15mm, sub-densely scaly outside, glabrous inside, straight, the base pouched; lobes 15–18 x 13–15mm, spreading, slightly reflexed, overlapping c.½, obovate-spathulate. Stamens sub-equal, at the mouth of the tube; filaments c.13mm, linear, glabrous, pink; anthers c.3mm, oblong, pale-brown, cells obtuse or narrowed into a short distinct basal apiculus. Disc prominent, glabrous. Ovary c.4–4.5 x 2–3mm, sub-ovoid-conical, apex obtuse, abruptly contracted distally, densely scaly and occasionally with some very sparse hairs; style 9 x 1mm, glabrous, or scaly at the base for c.1mm, red, as long as the stamens; stigma c.2mm in diameter, red, rounded. Fruit 14–18 x 7–8mm, ovoid-fusiform, brown-scaly. Seeds 1.7mm, without tails c.1mm, the longest tail 0.4mm.
Malaysia (Borneo), Sabah, Mt Kinabalu.
In forest above 3100m, but more frequent in shrubberies and in open places amongst the granite rocks, up to 3900m.
R. buxifolium var. robustum Sleumer, Reinwardtia 1960. 5: 173.
Argent, G. (2006) Rhododendrons of subgenus Vireya. RHS:London. Page:202