Description

Erect shrub or tree to 5m, or occasionally up to 10m. Twigs 1.5–2mm in diameter, rounded, at first densely covered with sub-stellate, stalked scales, becoming glabrescent, warty and rough to the touch; internodes 1.5–4cm. Leaves in loose pseudowhorls at the upper ends of the internodes or spirally arranged in the upper ½ of the internode. Blade 10–35 x 6–20mm, elliptic, ovate-elliptic or ovate; apex broadly tapering, obtuse or rounded; margin not or slightly cartilaginous, distinctly crenulate, slightly or not revolute; base tapering to rounded, rarely sub-cordate, dark green above, much paler and often yellowish green or brownish beneath, densely scaly initially on both sides, early glabrescent but densely marked with blackish minute pits above, more persistently and densely scaly beneath. Scales round to angular, distant, or only partly touching each other, the thin, marginal zone irregularly crenate or shortly sub-stellately lobed; centre relatively large, dark yellow, thick and a little impressed. Mid-vein narrowly impressed above, prominent beneath proximally, less so distally; lateral veins 4–7 per side, spreading, faintly impressed above and raised beneath in fully mature leaves, often inconspicuous. Petiole 1–3 x 1.5–5mm, grooved above, densely scaly. Flower buds to 11 x 6mm, pale greenish-brown, ovoid, acutely pointed, smooth, densely scaly outside, often with lateral flower buds around the terminal bud. Bracts to 10 x 4mm, ovate; outer acute or apiculate; inner obtuse, thin and membranous, with scales along a broad outside middle line, or quite glabrous and shining; margin irregular with a few brown scales. Bracteoles to 10mm, linear proximally, sub-spathulate distally, sparsely scaly. Inflorescence 3–7-flowered in an open umbel, half-hanging to hanging. Pedicels 8–14mm, slender, densely covered with shortly stalked scales. Calyx 2.5–3.5mm in diameter, disc-shaped, irregularly, very shortly and obtusely 5-lobed, densely scaly outside. Corolla 11–16mm, shortly tubular, pink to red, densely covered with thick, sub-stellate, yellow scales outside, glabrous inside; tube 7–12 x 4 x 6mm, straight; lobes 3–4.5 x 3–4.5mm, erect or only slightly spreading, sub-circular. Stamens exserted to c.3mm, unequal; filaments filiform, glabrous; anthers c.1mm, obovoid. Disc low, glabrous. Ovary 3–4 x 1.5–2mm, ovoid-conical, very densely covered with thick sub-circular scales, abruptly tapering distally; style thick, quite glabrous, as long as the ovary; stigma rounded to deeply 5-lobed. Fruit 12–17 x 4–5mm, fusiform-cylindrical, longitudinally 5-ribbed, somewhat curved, densely scaly, with a sub-persistent style. Seeds c.3mm including the tails.

Distribution

Indonesia and Papua New Guinea. Widespread in New Guinea, from the Vogelkop Peninsula, Arfak Mts, in the west along the Main Range to Mt Dayman in the Milne Bay District in the east.

Altitude

Habitat

In mossy forest or forest openings, Vaccinium-shrubbery, commonly on old landslides, the edges of deep gullies or steep mountainsides with grassy slopes in full sun, often on infertile sandy soil, sometimes on limestone ridges, locally common

Nomenclatural History

R. invasiorum Sleumer, Reinwardtia 1960. 5: 60. R. luteosquamatum Sleumer, Reinwardtia 1960. 5: 166.

Notes

References

Argent, G. (2006) Rhododendrons of subgenus Vireya. RHS:London. Page:228