Description

Shrub to 80cm. Twigs 3–4mm in diameter, rounded, green, finely brown scaly; internodes 3–15cm. Leaves 4–6 together in tight pseudowhorls. Blade 50–80 x 25–40mm, obovate, elliptic or broadly elliptic; apex obtuse to rounded, sometimes minutely mucronate; margin entire, flat when fresh, becoming slightly revolute when dry; base rounded to cordate; quickly glabrescent above, more densely, persistently scaly beneath. Scales brown, rounded to irregularly lobed, c.0.1mm in diameter, weakly impressed into shallow pits. Mid-vein impressed into a narrow groove above, only slightly raised beneath; lateral veins 3–5 per side, inconspicuous, reticulation obscure. Petiole 2–3 x 4–5mm, grooved above, green or with a faint reddish flush on the upper side, scaly. Flower buds (see p.327) c.40 x 20mm, green, narrowly ovate, acute, the bracts standing out from the buds at an acute angle with a ‘spiky’ appearance. Bracts to 30 x 14mm, ovate elliptic below but narrowly acuminate with channelled and inrolled upper margins; margins minutely scaly otherwise glabrous, shiny green in the central and upper parts, translucent towards the lower margins. Inflorescence 9–14 flowers in an open or one-sided umbel. Pedicels c.20 x 2mm, dark-pink, pale brown scaly and minutely covered with patent white hairs. Flowers half-hanging to semi-erect. Calyx forming a low irregular disc covered with hairs and scales. Corolla c.50 x 40mm, pure white with a faint sweet scent; tube c.40 x 8 x 5mm, distinctly narrowed upwards, glabrous outside, inside covered with moderately dense patent hairs; lobes c.19 x 20mm, circular or nearly so, overlapping for at least ½ their length and spreading at right angles or a little reflexed, glabrous. Stamens irregularly filling the mouth of the corolla tube but not exserted; filaments white, with some short white patent hairs in the proximal 5mm otherwise glabrous; anthers 2.5–3mm, pale brown, weakly apiculate at the base. Disc green, minutely hairy on the upper side. Ovary 6–7 x c.3mm, densely white scaly and with short white slightly distally directed simple hairs, gradually tapering; style scaly in the proximal ¼ and with semi-erect hairs in the proximal ½, completely glabrous distally, pink at the base, becoming white; stigma c.3mm in diameter, white, rounded, remaining within the mouth of the flower.

Distribution

Malaysia (Borneo), Sarawak, Fifth Div. Route from Bakelalan to Mt Murud; Mt Murut, Lawas; Mt Api, Fourth Div., summit ridge; Bario, Ulu Baram, path to Kuba’an Pungor Pwan; Secondary Peak of Batu Lawi. Sabah, Mt Lumarku, Sipitang District.

Altitude

Habitat

Epiphytic in large trees in montane mossy forest, or terrestrial on deep peat, sometimes in ultrabasic areas

Nomenclatural History

Notes

References

Argent, G. (2006) Rhododendrons of subgenus Vireya. RHS:London. Page:166