Herbs, terrestrial. Roots 3-10, from bases of newer corms, spongy. Stems produced in summer, solitary, subapical, opposite leaf, arising from ovate, angular corms. Leaves produced in autumn, persisting over winter, withering in spring, solitary; blade broad, ovate, pleated. Inflorescences lax racemes. Flowers resupinate, bilaterally asymmetric; lip with long, free basal spur; column slightly arcuate; anther terminal, deciduous but retained on pollinaria for short time; pollinia 4, in 2 pairs, yellow, attached to elastic caudicle 1 mm with basal viscidium; stigma entire; rostellum a 2-fid flap enclosing viscidium. Fruits capsules, pendent, ovoid. Seeds 0.5-0.6 mm.
Sep and lateral pet similar, narrowly oblong or oblanceolate; lip 3- lobed, the lateral lobes basal, short and rounded, upturned, the terminal lobe long and slender; lip prolonged at base into a long, slender, horizontal spur; anther terminal on the column, with 2 pollinia; perennial herbs with a series of corms connected by short rhizomes, the youngest corm producing a single lf in autumn and then the next summer (after the lf has withered) an achlorophyllous, lfless scape bearing a few sheathing scales toward the base and a long, loose, bractless terminal raceme. 3, the others in e. Asia.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.