Plants 35-80 cm tall. Rootstock tuberous, cylindric to narrowly ovoid. Stem erect, stout, with several tubular sheaths at base, (3 or)4-6-leaved. Leaves cauline, alternate, widely spaced, elliptic to narrowly elliptic, 10-18 × 3-7.5 cm, base sheathing, apex obtuse or acute. Peduncle robust, with 3 or 4 foliaceous, lanceolate bracts; rachis 10-18 cm, 10-28-flowered; floral bracts narrowly lanceolate, 20-45 mm, basal ones exceeding flowers, apex acuminate. Flowers white; pedicel and ovary straight to slightly arcuate, cylindric, 18-25 mm. Dorsal sepal erect, forming a hood with petals, ovate, cymbiform, 7-8 × 5-6 mm, glabrous, 3-veined, apex obtuse or acute; lateral sepals reflexed, ovate, oblique, 8-9 × 4-5 mm, glabrous, 3-veined, apex acute. Petals linear, 6-7 × ca. 1.5 mm, 1-veined, apex obtuse; lip pendulous or spreading, linear, 13-15(-20) mm, entire, apex obtuse; spur pendulous, cylindric to filiform, 25-60 mm, much longer than ovary, slender, apex acute. Column 1-2 mm; staminodes conspicuous; anther locules almost parallel; connective rather broad, apex subretuse; pollinia obovoid, with slender caudicles and linear-ellipsoid viscidia; rostellum erect, broadly triangular, short; stigma lobes confluent, concave, lying directly below rostellum. Fl. Mar-Jul, fr. May-Sep. 2n = 42.
Home