(Lour.) Y.De Smet & C.Granados
Description
Hydrangea febrifuga, long familiar under the name Dichroa febrifuga, is a widely distributed shrub of subtropical and warm-temperate Asia, ranging from the Himalaya (Nepal, Sikkim, Bhutan, northeast India) eastward through southern China, Myanmar, Thailand and Indochina to Malesia and the Philippines. It inhabits moist, shaded forest, ravines and streamsides, forming part of the evergreen broad-leaved understorey. It is recorded from low to mid elevations; the populations shown above Yoksam in Sikkim at 2,300 m in August and at Laprak in the Gorkha region of Nepal at 2,000 m in May span its typical mid-montane range in humid forest.
The plant is an erect, much-branched shrub with subquadrangular, often purplish young stems. The leaves are opposite, elliptic to oblong-lanceolate, with a serrate margin, acuminate apex and a glabrous to sparsely pubescent surface. The inflorescence is a terminal or axillary corymbose to paniculate cyme bearing numerous small bisexual flowers; the calyx is shortly toothed and the corolla blue to violet or whitish with thick, valvate petals, the stamens conspicuous. Distinctively for the family, the fruit is a fleshy, indigo-blue berry crowned by the persistent calyx and containing many minute seeds.
Molecular phylogenetic work has shown the segregate genus Dichroa to be nested within Hydrangea, prompting the recombination as Hydrangea febrifuga by De Smet and Granados; the basionym traces to Loureiro's original description of Lourea. The species is of long-standing ethnomedical importance: its roots and leaves, rich in the alkaloid febrifugine, have been used in traditional Chinese and Himalayan medicine against malaria and fevers, a property reflected in the epithet. It remains common and is not considered threatened.
Author: (Lour.) Y.De Smet & C.Granados · Sources: POWO (Kew), Flora of China Vol. 8, Flora of Bhutan Vol. 1, GBIF, De Smet et al.: Hydrangea phylogeny (TAXON)