Description

Shrub to 2.5m. Twigs 2–3mm in diameter, sparsely scaly and papillose-hairy in the youngest parts, becoming glabrescent; internodes 2–10cm. Leaves 3–5 together in tight pseudowhorls. Blade 40–100 x 15–45mm, obovate-elliptic; apex obtusely tapering or nearly rounded; margin entire, slightly revolute in dry specimens; base tapering or broadly tapering, glabrescent above when mature, sub-persistently and sub-densely to laxly scaly beneath. Scales small, with the marginal zone irregularly lobed and a minute dark centre, slightly impressed, each scale surrounded by a dark halo, also very finely punctate by minute emergences of the epidermis beneath. Mid-vein slightly depressed and with minute, papillose, spreading hairs above, as wide as the petiole and obtusely prominent in the lower part beneath; lateral veins 6–10 per side, spreading, obscurely inarched at the margin, slightly prominent on both sides, reticulation inconspicuous. Petiole 6–12 x 1–1.5mm, with minute, papillose, spreading hairs above. Outer bracts to 15 x 8mm, ovate, obtuse, inner ones oblong-obovate, laxly scaly and minutely hairy outside, becoming glabrescent, fringed with scales. Bracteoles to 23 x 0.5–4mm, filiform below, spathulate distally, papillose. Inflorescence a 4–10-flowered umbel. Pedicels 8–12mm, slender, laxly to sub-densely scaly and finely patently hairy. Calyx c.3mm in diameter, disc-shaped, membranous, sub-obtusely and very shortly unequally lobed, wavy, spreading to reflexed, glabrous outside, distinctly ciliate. Corolla 25–35mm, tubular below, expanded upwards, oblique, deep pink; tube 15–20 x 3–4 x c.5mm, sub-cylindrical, straight or slightly curved, glabrous outside, laxly hairy inside; lobes 7–10 x 5–8mm, sub-erect, or somewhat spreading, obovate-spathulate. Stamens spreading all round the mouth, unequal, the longest as long as the corolla; filaments linear and laxly hairy below, filiform and glabrous distally; anthers 2mm, obovate. Disc shortly hairy. Ovary c.4 x 2mm, sub-cylindrical, densely short-hairy and minutely scaly (the scales covered by hairs), abruptly contracted distally; style slender, sometimes with some hairs at the very base, equalling the stamens in length; stigma club-shaped, obconical, oblique. Fruit (sub-mature) 20 x 4mm, fusiform, densely hairy, surmounted by the glabrous, 20mm style.

Distribution

Indonesia, New Guinea (W), Arfak and Nettoti Mts.

Altitude

Habitat

At the edge of forest,locally common, epiphytic or more rarely terrestrial.

Nomenclatural History

R. undulaticalyx J.J.Sm. in Gibbs, Phyto. Fl. Arfak Mts. 1917. 168.

Notes

References

Argent, G. (2006) Rhododendrons of subgenus Vireya. RHS:London. Page:309