Lindl.
Description
Bulbophyllum hirtum is an epiphytic orchid distributed across the eastern Himalayas and Southeast Asia, from Nepal and northeast India through Bhutan, Myanmar, southwest China, Thailand, and Vietnam. It grows in warm to temperate broadleaved forests at 500–2,000 m elevation, on moss-covered tree trunks and larger branches, occasionally on rocks near streams.
The plant has ovoid, somewhat compressed pseudobulbs 1.5–2.5 cm tall, spaced 2–5 cm apart on a creeping rhizome. Each pseudobulb bears a single, elliptic-oblong, coriaceous leaf 6–12 cm long. The inflorescence is a lax raceme 5–15 cm long, carrying 5–15 flowers. The specific epithet 'hirtum' (meaning hairy) refers to the distinctive pubescence on the floral parts: the flowers are small, 6–10 mm across, yellowish to brownish-green with conspicuous fine hairs on the sepals and petals. The lip is fleshy, recurved, and densely papillose, dark purple, hinged to the column foot. Flowering occurs from September to November.
Bulbophyllum hirtum is classified within Bulbophyllum section Brachystachya. The pubescent flower surfaces are thought to play a role in pollinator attraction by enhancing both visual texture and scent dispersal, as the genus is predominantly pollinated by small flies (Diptera).
Author: Lindl. · Sources: POWO (Kew), Flora of Bhutan Vol. 3, GBIF, Vermeulen: Orchid Monographs 7: Bulbophyllum (1993)