Description from Flora of China
Herbs epiphytic, lithophytic, or terrestrial. Pseudobulbs annual, often clustered, ovoid, conic, pyriform, or turbinate, gradually narrowed toward apex to form a distinct neck, sometimes abruptly contracted into a very short neck, 1- or 2-leaved at apex. Leaves usually papery, plicate, usually contracted at base into a short petiole-like stalk, usually deciduous or falling in winter. Inflorescences 1 or 2, arising from base of an old pseudobulb, erect, appearing either before or after leaves, 1- or 2-flowered; floral bracts often colorful, persistent. Flowers large, usually showy, opening widely, sometimes fragrant. Sepals usually free, similar. Petals similar to but usually slightly narrower than sepals; lip conspicuously larger than sepals, entire or obscurely 3-lobed, sometimes basally adnate to column base, apical margin erose or lacerate; disk with a callus consisting of 2 to several lamellae or rows of papillae extending along central veins. Column slightly arcuate, slender, winged above, apex usually erose; pollinia 4, in 2 pairs, waxy, often obovoid and bilaterally flattened. Capsule fusiform, with 3 longitudinal ribs.
About 26 species: from Nepal, across C, S, and E China and Bhutan, south to Laos, Myanmar, Thailand, and Vietnam; 23 species (12 endemic) in China.
(Authors: Chen Xinqi (陈心启 Chen Sing-chi); Phillip J. Cribb, Stephan W. Gale)