A small, compact, evergreen shrub often found wild on trees growing as an epiphyte, or on rocks and only a few inches high. Shoots thickly set with leaves and rough with wart-like glands the first year, densely furnished with stalked glands the second. Leaves obovate to oblanceolate, with a notched, mucronate apex, tapering to a stout winged stalk, 1⁄2 to 11⁄4 in. long, 1⁄4 to 1⁄3 in. wide, glabrous except for a few scattered scales. Flowers solitary or in pairs, terminal. Corolla pink or white tinged with pink, tubular at the base, 1⁄5 in. long, spreading at the mouth into five rounded lobes each 1⁄5 in. long, with scattered glandular scales outside. Stamens ten, hairy on the middle part only. Ovary scaly, tapered at the apex into a short stout style. Seeds with a long tail at each end. Bot. Mag., t. 9407b.
Native of the eastern Himalaya, Assam, upper Burma, N.W. Yunnan and bordering parts of S.E. Tibet; discovered by J. D. Hooker in Sikkim and introduced by him in 1850, but the seedlings soon died off. It is of no value for gardens, the flowers being even smaller than they are in R. micranthum, but is of interest as a member of the section Vireya, characterised by the long-tailed seeds, which has its main distribution in Malaysia, New Guinea, and the Philippines. In Sleumer's classification it belongs to the subsection Pseudovireya, of which it is the type-species. The Vaccinioides series, as defined in The Species of Rhododendron, comprises those members of this subsection which occur in the Sino-Himalayan region, Formosa and the Philippines (and includes one species – R. vidalii – which is considered by Sleumer to belong to the typical subsection of Vireya).
From the Supplement (Vol. V)
It was mentioned that the section Vireya subsect. Pseudovireya (the former Vaccinoides series) has a representative in Formosa (Taiwan). This is R. kawakamii Hayata, for which see Davidian, The Rhododendron Species, Vol. 1, p. 391. It was introduced by the American collector John Patrick in 1969. Also in this group is R. santapaui Sastry & Kataki, discovered by Peter Cox and his companions in the Apa Tani valley of the Assam Himalaya (Arunachal Pradesh) in 1965 (Davidian, op. cit., p. 391; Cox, Dwarf Rhododendrons, plate 36). Both are tender and the latter also difficult to cultivate.