(C.B.Clarke) Harry Sm.
Description
Megacodon stylophorus is a stately giant gentian of the eastern Himalaya and southwestern China. GBIF records it from China, India, Bhutan, Nepal and Myanmar, with roughly 450 occurrences, the genus being a small Sino-Himalayan endemic. It grows in moist subalpine meadows, forest clearings, scrub margins and along streamsides between about 3000 and 4300 m. The plant shown was photographed on the Chele-La pass in western Bhutan at 3900 m in July, when its tall flowering stems rise above the surrounding alpine herbage at the height of the monsoon growing season.
It is one of the largest herbaceous gentians, an erect perennial reaching 1-1.5 m from a stout rhizome. The stem bears opposite, sessile, broadly ovate leaves with conspicuous arcuate parallel venation. The large, pendulous, broadly campanulate flowers are borne in the upper leaf axils; the corolla is pale greenish-yellow, intricately net-veined with darker reticulation, and 4-5 cm long. Distinctively the style is long and persistent (the epithet stylophorus, style-bearing), exserted from the corolla, and the fruit is a large septicidal capsule releasing numerous winged seeds adapted to wind dispersal.
Megacodon is a segregate from the broadly defined Gentiana, distinguished by its great stature, reticulate corolla and elongate style, and molecular studies place it among the basal lineages of tribe Gentianeae. Its showy net-veined flowers are pollinated chiefly by bumblebees foraging at high elevation. Though striking and of horticultural interest, it is not regarded as globally threatened, but its dependence on undisturbed, moist subalpine habitats makes it sensitive to overgrazing and shifting monsoon regimes.
Author: (C.B.Clarke) Harry Sm. · Sources: POWO (Kew), GBIF, Flora of China, Flora of Bhutan, Annotated Checklist of the Flowering Plants of Nepal, Gentianaceae: systematics and natural history