J.J.Sm.
Description
Bulbophyllum yoksunense is a rare epiphytic orchid with a restricted distribution in the eastern Himalayas. The species is named after Yuksom (also spelled Yoksum or Yoksun) in western Sikkim, India, where the type specimen was collected. Its known range includes Sikkim, Bhutan, eastern Nepal, and northern Myanmar. With only 17 documented occurrences in GBIF, it is among the less frequently recorded Bulbophyllum species in the region. It grows on mossy tree trunks in temperate broadleaved forests at 1,500–2,500 m elevation.
The pseudobulbs are ovoid, 1–2 cm tall, closely set on a creeping rhizome. Each bears a single, elliptic, coriaceous leaf 5–10 cm long. The inflorescence is a short, few-flowered raceme. Flowers are small, about 8–12 mm across, with distinctive coloration: the sepals are pale greenish-yellow with fine purple veining, and the lip is dark purple, fleshy, and slightly recurved. The lateral sepals are slightly longer than the dorsal sepal. Flowering in Bhutan occurs in October.
B. yoksunense is poorly known in cultivation and in the wild. Its apparent rarity may partly reflect under-collection in the remote eastern Himalayan forests of Bhutan and Sikkim. Further field survey is needed to clarify its true distribution and conservation status.
Author: J.J.Sm. · Sources: POWO (Kew), GBIF, Pearce & Cribb: The Orchids of Bhutan (2002), J.J. Smith: Orchidaceae Novae (1910)