Description from Flora of China
Herbs, epiphytic, monopodial, small to medium-sized. Stems pendulous or ascending, sometimes climbing, short or elongate, with a few to many nodes. Leaves several to many, distichous, narrowly oblong, flat, leathery, with sheathing base, usually unequally bilobed or retuse. Inflorescences lateral, paniculate or racemose, pendulous or ascending, many flowered; peduncle long. Flowers resupinate or not, usually opening widely, small. Sepals and petals free, similar, spreading. Lip firmly attached to column, immovable, fleshy, shortly spurred or saccate, 3-lobed; lateral lobes erect, deltoid, small; mid-lobe often recurved, usually suborbicular or ovate-triangular, fleshy; front wall fleshy, thickened, back wall with a projecting, erect, bifurcate, ligulate appendage reaching or exserted beyond entrance. Column short, stout, foot absent; anther cap shortly beaked; rostellum large, hamulate, ± bifid, shorter than diam. of column; pollinia 4, as 2 discrete unequal pollen masses, waxy, subglobose, with a long common stipe and a solitary small, usually concave viscidium.
See the treatment by Watthana (Harvard Pap. Bot. 11: 207-256. 2007).
Thirteen species: from India through Malesia and N Australia to Fiji, north to NE Himalayas and Taiwan; two species in China.
(Authors: Chen Xinqi (陈心启 Chen Sing-chi); Jeffrey J. Wood)