Herbs, epiphytic or lithophytic. Rhizome creeping. Pseudobulbs close together, cylindric to ovoid-globose, sometimes prostrate basally, 1-or 2-leaved. Leaves conduplicate, petiolate to subsessile, linear-lanceolate, thinly leathery, acute. Inflorescence synanthous, proteranthous, or heteranthous, 1-8-flowered, erect to decurved; floral bracts persistent, shorter than ovary. Flowers resupinate, variously colored. Sepals free, similar, lateral sepals often oblique or slightly narrower and longer. Petals similar to sepals, often shorter and narrower; lip entire or 3-lobed; lateral lobes small, not clasping column, sometimes basally sigmoid, often with short keels or lamellae. Column ca. as long as or much shorter than lip, with or without stelidia, foot abbreviated or almost absent; anther overhanging; pollinia 4, obliquely obovoid, with caudicles; stigma cup-shaped; rostellum large. Capsule ellipsoid.