Benth.
Description
Arenaria festucoides Benth. is a tufted alpine sandwort of the Caryophyllaceae, distributed through the Himalaya and Tibetan plateau in India, Nepal, Pakistan and SW China, with around 126 georeferenced records concentrated along the high Sino-Himalayan ranges. It is a plant of open, well-drained habitats: stony alpine meadows, gravel flats, fine scree and grassy slopes above the treeline, where it forms low patches among rocks. The photographed population from Bagubasa in the Garhwal Himalaya at about 4,150 m in September lies squarely within its typical high-alpine elevational range, where it flowers and fruits late in the short mountain summer. In GBIF the name is treated as a synonym, but the accepted name is likewise rendered Arenaria festucoides, so it stands as the valid designation here.
The species is a densely caespitose perennial forming firm cushions or mats from a branched woody caudex. The leaves are crowded, narrowly linear to subulate and rigid, grass-like (hence the epithet festucoides), often pungent-tipped and somewhat keeled. The small flowers are borne singly or in few-flowered cymes on short pedicels; the five free sepals are lanceolate and acute, exceeded by the five entire white petals. There are typically ten stamens and three styles, the ovary maturing into a small ovoid capsule that dehisces by valves to release several minute seeds.
Arenaria is a large and taxonomically complex genus, and several segregate genera (Eremogone, Odontostemma) have been carved from its Himalayan members, so generic placement of this and allied species has shifted in recent treatments. The compact cushion habit, reduced leaf surface and deep caudex are classic adaptations to wind exposure, drought and frost at high elevation. The species is widespread across its range and not regarded as threatened.
Author: Benth. · Sources: POWO (Kew), Flora of China Vol. 6, Flora of Pakistan, GBIF, McNeill: Taxonomic studies in the Alsinoideae (1962)