Herbs, epiphytic, monopodial. Stems ascending or rarely arching, usually rather long, stout, rigid, with short internodes and many distichous leaves, with thick roots in lower part. Leaves distichous, flat, narrow, often closely spaced, linear to lorate, conduplicate toward base, with amplexicaul-sheathing base, jointed. Inflorescences erect or suberect, racemose, axillary, usually ascending, sparsely few to many flowered. Flowers large or medium-sized, usually colorful and long-lasting. Sepals and petals similar or sepals wider, often narrowed toward base, margins ± twisted or wavy, often tessellated; lip attached to an indistinct column foot, immobile, shortly spurred, 3-lobed; lateral lobes erect, small; mid-lobe large, usually with longitudinal keels or swellings adaxially. Column short, stout; rostellum short; anther cap subglobose; pollinia 2, subglobose, waxy, each strongly cleft or porate, attached by a common short stipe to a large viscidium.