Terrestrial with leafy pseudobulbs or stems, sometimes both pseudobulbs and stems present. Leaves with tubular sheaths enclosing stems, plicate. Racemes arising from base of pseudobulb or lower part of stem; bracts persistent or caducous. Flowers often large and showy; sepals and petals subequal, free and +/-spreading; lip spurred, joined to base of column or rarely fused with base of column, base narrow, apex enlarged, folded and more or less embracing column, shallowly or indistinctly 3-lobed toward apex; lateral lobes erect or incurved, central lobe usually retuse, crispate; disc often keeled; column slender, dilated,+/- winged at apex, usually free from lip or rarely connate near base with base of lip; anther terminal, incumbent, opercular, incompletely 4-celled; pollinia 8, waxy, laterally flattened, in two groups of 4, with short tips attached to a tape-like caudicle, without distinct viscidium; stigmatic surface solitary, rostellum broadly tongue shaped, undivided, recurved.
About 40 species, widely distributed from East Africa and Madagascar through tropical Asia and Indonesia to New Caledonia and Fiji. Four species in Taiwan.