K.K.Shrestha
Description
Cyananthus himalaicus is a high-alpine perennial known from the central and eastern Himalaya, with GBIF records concentrated in Nepal (gbif_countries: NP) and only seven documented occurrences, indicating a narrowly recorded and infrequently collected taxon. Like its congeners it inhabits open alpine turf, rocky slopes, screes and the margins of glacial meltwater, growing well above treeline in the cool, short-season environments of the inner ranges. The illustrated material was gathered near Saniti Lake in Sikkim at about 4250 m in August, when the late-summer flush of alpine flowering coincides with the waning monsoon, a habitat typical for the genus along the moist Himalayan crest.
The plant forms low, often mat-like or loosely tufted growth from a slender woody rootstock, with prostrate to ascending stems bearing small, alternate, entire to shallowly toothed leaves that are frequently revolute and somewhat fleshy. The flowers are solitary and terminal, with a campanulate to tubular corolla that is typically blue to violet-blue, five-lobed, and bearded within the throat by a ring of hairs, a hallmark of Cyananthus. The calyx is tubular and densely hairy, and the fruit is a capsule enclosing numerous small seeds.
Cyananthus is a Sino-Himalayan genus of the bellflower family centred on the alpine zone, and C. himalaicus belongs to the assemblage of small-flowered, prostrate species adapted to exposed, well-drained high-mountain sites. Its limited occurrence data reflect under-collection in remote terrain rather than necessarily a restricted range; nonetheless its apparent rarity in records argues for attention to its alpine habitats, which are sensitive to grazing pressure and climatic warming.
Author: K.K.Shrestha · Sources: POWO (Kew), GBIF, Flora of Nepal, Flora of China, Annotated Checklist of the Flowering Plants of Nepal, Revision of the genus Cyananthus (Campanulaceae)