Epiphytic herbs. Stems short or elongate, erect or pendulous, branching and rooting at base. Leaves often distichous, narrow, thick and fleshy, articulated with sheaths at base. Inflorescences simple or branched, erect or horizontal, bearing many small flowers. Flowers fleshy; sepals and petals similar, not widely spreading, often broad, petals often narrower; lip thickly fleshy, joined firmly to base of column, spurred at base, 3-lobed, often with a callosity or appendage at entrance to spur, lateral lobes erect, mid-lobe fleshy, often angled, spur cylindric or ellipsoid, sometimes septate; column stout, without foot; anther terminal, operculate, 1-celled; pollinia 2, often divided into unequal halves or deeply sulcate, attached to a broad ovate-rhombic viscidium by short stipe.
More than 20 species, from the Himalaya, India, Indochina and the Philippines, through Malaysia and Java to Papua New Guinea and the Pacific islands. One species in Taiwan.