Bulbophyllum nigrescens (at XTBG, by Zhu Renbin)

Bulbophyllum nigrescens is a species of orchid in the genus Bulbophyllum.

Found in Thailand, Yunnan Province China and Vietnam in sparse woods growing on tree trunks at elevations around 400 to 1500 meters as a miniature sized, warm to cool growing lithophye or epiphyte with squat, globular, flattened ventrically, rugose pseudobulbs carrying a single, apical, linear to lanceolate leaf that blooms in the late winter and early spring.