Epiphytic or lithophytic herbs. Rhizome creeping. Pseudobulb ovoid or dilated, covered by several acute, imbricate, brown sheaths below, one-leaved at apex or bearing two or three leaves toward the apex, covered when young by acute sheaths. Leaves coriaceous, suberect to erect, conduplicate, coriaceous, articulated to apex of sheath. Inflorescence terminal, synanthous, racemose, secund; floral bracts prominent, lanceolate, almost as long as the flowers. Flower campanulate or opening widely, spreading or subnutant, resupinate, glabrous, white, pink, red, or yellow. Sepals fused into a cylindrical tube except for their apical quarter or dorsal sepal free, lateral sepals oblique at base, attached to column foot to form a conical mentum. Petals smaller than sepals, free, oblanceolate. Labellum entire and ecallose or trilobed and callose, recurved in apical half, lacking a spur, firmly attached to column foot to form an obscure mentum. Column with a column foot as long as or longer than column; anther eight-locular; pollinia eight, clavate, attached to a prominent, elongate, narrowly elliptic viscidium, bifid at apex; rostellum prominently bilobed. Ovary markedly keeled, triangular in cross-section. (PC, YN).