Hook.f. & Thomson
Description
Corydalis leptocarpa is a Sino-Himalayan to East Asian fumitory recorded from China, Bhutan, India, Myanmar, Japan, Nepal, Thailand and Korea, with around 163 GBIF occurrences spanning this broad temperate range. It is a plant of shaded, humid forest, woodland margins, mossy banks and damp ravines, typically at montane elevations from roughly 1500 to 3000 m. The individual photographed near Trashiyangtse (Trachyangtse, eastern Bhutan) at about 2300 m in May illustrates its association with moist broad-leaved forest in spring, when the slender stems and pale flowers appear in the dappled understorey.
The species is a slender, erect to ascending annual or short-lived perennial herb with brittle, somewhat glaucous foliage. The leaves are bi- to triternately compound, the ultimate segments ovate and lobed, borne on delicate petioles. The inflorescence is a lax raceme of pale yellow, zygomorphic flowers; each has four petals, the upper outer one prolonged backward into a slender spur, enclosing two stamen bundles and an elongate ovary. The fruit, as the epithet leptocarpa ('slender-fruited') indicates, is a narrow, linear, pendulous capsule that dehisces elastically to scatter the shining black seeds, which often bear an oily elaiosome.
Corydalis is one of the largest genera of the Papaveraceae (subfamily Fumarioideae), exceptionally diverse in the Sino-Himalaya, where hundreds of species occupy habitats from forest floor to alpine scree. C. leptocarpa belongs to the yellow-flowered woodland element of the genus. Many Corydalis species rely on ant-mediated seed dispersal of their elaiosome-bearing seeds. With its wide East Asian range and tolerance of forest-edge habitats it is not considered threatened, though it remains tied to intact montane forest cover.
Author: Hook.f. & Thomson · Sources: POWO (Kew), GBIF, Flora of China, Flora of Bhutan, Annotated Checklist of the Flowering Plants of Nepal, Lidén & Zetterlund monograph of Corydalis