C.B.Clarke
Description
Crawfurdia speciosa C.B.Clarke is a climbing perennial gentian of the eastern and central Himalaya, distributed through Nepal, north-east India, Bhutan, south-west China and into northern Vietnam, with scattered records from Bangladesh and Pakistan. It is a plant of moist, shaded temperate forest, scrambling through shrubs and over the herbaceous understorey along forest margins, stream banks and clearings. The two photographed Bhutanese populations bracket its altitudinal span, from the warm Mo-Chu valley at 1900 m to the cool Tumching-La pass at 3200 m, both flowering in October. This autumn flowering, well after the monsoon, is characteristic of the twining Asian gentians and exploits the late-season window before the onset of winter.
Unlike the familiar erect, rosette-forming gentians, Crawfurdia is a slender, herbaceous, twining climber with weak quadrangular stems and opposite, ovate to ovate-lanceolate leaves tapering to an acuminate tip and bearing prominent palmate-curved venation. The flowers, solitary or few in the upper leaf axils, are showy and pendent; the campanulate to tubular corolla is blue to blue-purple, with short spreading lobes and conspicuous plicate folds (plicae) between them, a hallmark of the gentian family. The fruit is a stalked, flattened capsule that protrudes from the persistent corolla on an elongating gynophore, releasing numerous small, winged, wind-dispersed seeds.
The genus Crawfurdia is closely allied to Gentiana and Tripterospermum, and has at times been merged with them; molecular studies confirm the twining Sino-Himalayan gentians as a distinct lineage. The pendent blue corolla suggests pollination by late-season bees. Though not currently regarded as threatened, its dependence on intact mid- to high-elevation forest makes it sensitive to deforestation across its eastern Himalayan range.
Author: C.B.Clarke · Sources: POWO (Kew), GBIF, Flora of China (Gentianaceae), Flora of Bhutan, Annotated Checklist of the Flowering Plants of Nepal, Gentianaceae: Systematics and Natural History (Struwe & Albert)