Duthie ex Huth
Description
Delphinium densiflorum is a herbaceous perennial of the western and central Himalaya, recorded from India, Nepal and adjacent China (Xizang), with some 70 georeferenced occurrences documented in GBIF. It inhabits subalpine and alpine meadows, open slopes, forest margins and rocky grassland, where it flowers in the late monsoon. The plant illustrated was photographed in the Indian Garhwal Himalaya near Ali at about 3140 m in September, a typical elevation; across its range it generally occupies the belt from roughly 2800 to 4000 m, favouring moist, well-drained soils with abundant summer rainfall.
The species forms an erect, simple or branched stem arising from a fibrous to slightly tuberous rootstock, clothed below with petiolate, palmately divided leaves whose laminae are deeply cut into narrow, toothed lobes. As the specific epithet implies, the inflorescence is a dense, many-flowered raceme of strongly zygomorphic flowers. Each flower has five petaloid sepals, the uppermost prolonged into a conspicuous backward-pointing spur, and small petals modified into nectaries concealed within. The flowers are typically deep blue to violet; the fruit is a cluster of several erect, beaked follicles releasing numerous angular, scaly seeds.
Delphinium densiflorum belongs to the large genus Delphinium (Ranunculaceae), of which the Himalaya is a notable centre of diversity. Like other larkspurs it contains diterpenoid alkaloids and is poisonous to grazing livestock, a trait that influences its persistence in heavily pastured alpine meadows. The spurred flowers are adapted to pollination by long-tongued bumblebees. No major conservation concern is recognised, though localised pressure from grazing and habitat disturbance affects subalpine populations across the region.
Author: Duthie ex Huth · Sources: POWO (Kew), GBIF, Flora of China, Flora of Bhutan, Annotated Checklist of the Flowering Plants of Nepal, Munz Monograph of the Genus Delphinium