Maxim.
Description
Saussurea stella is a high-alpine herb distributed across the eastern Himalaya and the Tibetan Plateau, recorded from China (Xizang, Yunnan, Sichuan, Qinghai, Gansu), Bhutan and India, with some 821 georeferenced occurrences documented in GBIF. It occupies open alpine meadows, marshy turf, gravelly flushes and the margins of glacial streams, typically between 3000 and 5400 m. The plant photographed at Yume Samdong in northern Sikkim at about 4600 m in August is characteristic of the wet, peaty seepage slopes the species favours during the monsoon, where it forms part of a low cushion-and-rosette sward exposed to intense radiation, nightly frost and a brief growing season.
The species is a stemless, near-acaulescent perennial forming a flat, star-shaped rosette pressed against the substrate from a stout taproot. The numerous lanceolate to linear leaves are glabrous, entire and often suffused with purplish-red, radiating symmetrically and giving the plant its epithet stella. The capitula are sessile and densely clustered at the rosette centre, each involucre with imbricate, purple-tinged phyllaries enclosing tubular purple florets; the corollas are deeply lobed and the anthers tailed at the base. Fruit is a glabrous cylindrical achene with a double pappus of short outer and longer plumose inner bristles.
A member of the large genus Saussurea (subtribe Saussureinae, tribe Cardueae), S. stella belongs to the rosette-forming, ground-hugging guild that recurs in Tibetan alpine floras as an adaptation to cold, windy, high-irradiance environments, the flattened habit and dark pigmentation enhancing heat capture and protecting against ultraviolet stress. Pollination is by alpine flies and bees, and the plumose pappus enables wind dispersal. Though not formally assessed as threatened and locally abundant, it is sensitive to grazing and the warming-driven contraction of alpine seepage habitats.
Author: Maxim. · Sources: POWO (Kew), GBIF, Flora of China, Flora of Bhutan, Lipschitz Monograph of Saussurea