17. Spiranthes L. C. Rich., Orch. Eur. Annot. 20. 1817. nom. cons; Hook.f., Fl. Brit: Ind. 6: 102. 1890; Renz in Rech. f., Fl. Iran. 126:49. 1978.
Plants slender, with shortened rhizome and fasciculate, fleshy roots. Leaves radical or cauline, petiolate. Inflorescence terminal, rachis often spirally twisted. Flowers resupinate, white, whitish-green, pale yellow or rose. Perianth segments subequal; the dorsal sepal adhering with petals to form a hood; lateral sepals ± spreading. Labellum sessile, spurless, entire, somewhat constricted in the middle, front with ± undulate-erose margin. Column short; anther dorsal, erect; pollinia 2, mealy, with short caudicles, fixed on a mutal viscid gland; rostellum prominent, erect, bifid, with the viscidium inserted in the bifurcation; stigmata 2, ± confluent. Ovary sessile, twisted.
A widely distributed genus of c. 50 species in the temperate and tropical regions of the Old and New World, Australia and New Zealand, in Africa only in the mediterranean area.