erect herbs, rootstock horizontal, tuberous, glabrous or often with
multicellular hairs. Leaves simple, spirally arranged, ligulate with broad,
tubular sheath. Inflorescence on dense, globose or ovoid heads or spikes,
bracts spirally arranged, overlapping, each subtending 1 or 2 flowers. Flowers
bisexual, bilaterally symmetrical. Calyx 3-toothed, tubular or infundibuliform.
Corolla 3-lobed, somewhat fleshy, united below. Labellum showy. Stamens 3, one
fertile, lateral staminodes minute or
absent. Ovary trilocular, ovules many. Fruit a globose or ovoid capsule,
irregularly dehiscent. Seeds obovoid, aril short.