Australian Tropical Rainforest Plants - Online edition
Rhododendron viriosum Craven
Craven, L.A. (2002) Edinburgh Journal of Botany 59(3): 448-450. Type: cultivated in the Australian National Botanic Gardens at Canberra, 22 ii 1994, Craven 9354 (holo. CANB; iso. A, B, BRI, E, L, MEL, QRS). (Provenance: Queensland: Mount Windsor Tableland, 27 v 1989, Jones & Clements 4420 (CANB).
Rhododendron; Rhododendron, Native; Native Rhododendron
Usually grows as a terrestrial, lithophytic or epiphytic shrub.
Leaves in pseudowhorls of 2-6. Leaf blades rather thick and leathery, about 2.5-11 x 1-7 cm, cracking when folded. Apex acuminate to obtuse. Lateral veins 4-9 on each side of midrib, form loops inside the blade margin. Underside of the leaf blade marked by numerous dark peltate scales. Petiole channelled on the upper surface.
Umbel 2-7-flowered. Corolla funnel-shaped, straight, red to reddish-pink, 3.5-5 cm long in all, sparsely hairy outside and marked by scales. Stamens ten, anthers presented around the throat (more or less in a cicle, absent or rarely present in the upper part of the throat), anthers red; filaments red, hairy. Base of the ovary surrounded by a lobed disk with the staminal filaments inserted in the indentations. Pollen white. Ovary with scales, with dense white hairs. Basal half of the style clothed in scales and white hairs. Stigma 4-lobed.
Seed germination time 23 to 331 days. Cotyledons obovate, ovate to elliptic, about 1.5-3 x 0.5-1 mm. First pair of true leaves obovate, about 2-3 x 1 mm, apex obtuse, base cuneate, glabrous, petiole about 1 mm long, lateral veins not visible. At the tenth leaf stage: all seedling parts clothed in pale brown scale-like glands which are visible to the naked eye. Leaf blade elliptic-obovate, about 8 x 5 mm, apex obtuse, midrib depressed on the upper surface. Lateral veins difficult to distinguish. Terminal bud scaly.
Endemic to NEQ, occurs on Mt Lewis, Mt Spurgeon, Pinnacle Rock, the Windsor Tableland, Mt Finnigan, Mt Pieter Botte and Thornton Peak. Altitudinal range from 940-1330 m. Grows as an epiphyte in well developed rain forest but also found as a lithophytic shrub on boulders in stunted windswept rain forest on mountain tops.